CHM 1025 Exam 2

combination

Both metallic and nonmetallic elements can undergo combustion. In such instances, the reactions can also be classified as _______ reactions.

Sulfuric acid and calcium carbonate are the starting substances, the reactants. They are converted into carbon dioxide and calcium sulfate, the products. (Another product is water, which can't be identified from this description.)

Breanna mixed a solution of sulfuric acid and solid calcium carbonate. Carbon dioxide gas bubbled out of the solution as the initial solid disappeared, leaving behind a deposit of calcium sulfate. Identify the reactants and products in this chemical reaction.

seven; halogens

Bromine, in group VIIA (17), has _______ valence electrons, as do all the other elements, the _______, in that group.

noble-gas configurations

By convention, electron configurations are only abbreviated using _______________.

conservation of energy

By measuring the temperature change of the water, we can calculate the heat change of the water, qwater, using its specific heat. Assuming no heat is absorbed by the calorimeter, we can determine the heat change for the reaction, q(reaction), using the law of ________________: q(reaction) + q (water) = 0 q(reaction) = -q(water)

precipitate

A ______ is an insoluble ionic compound that does not dissolve in water.

sublevel

A ________ consists of just one type of orbital at a specific principal energy level.

bomb calorimeter

A _________ is commonly used to measure the amount of heat released in combustion reactions. The water absorbs the heat released by the reaction.

single-displacement

A ___________ reaction was responsible for severe corrosion that occurred in the Statue of Liberty.

cation (The nucleus holds the cation's fewer electrons more tightly. ) anion

A ____________ is smaller than the neutral atom from which it forms. An _______ is larger than the neutral atom from which it forms.

propane

C3H8 = ______

3CO2(g) + 4H2O(g)

C3H8(g) + 5O2(g) ---->_____ + _______

Ca(OH)2(aq) + H2SO4(aq) ---> CaSO4(s) + 2H2O(l)

Calcium oxide is the white powder, lime. When added to water, it makes slaked lime, which is a solution of the base calcium hydroxide. If sulfuric acid is added to slaked lime, calcium sulfate and water form. Write a complete, balanced equation for the reaction between sulfuric acid and calcium hydroxide.

aqueous calcium hydroxide and gaseous hydrogen. Ca(OH)2(aq) + H2(g)

Calcium reacts with water to form _____ and _____ Ca(s) +2H2O(l) --->_____ + ______

combination; compound and an element.

Carbon monoxide burns in air to form carbon dioxide. This is a ______ reaction between a _____ and a ______

water and carbon dioxide H2O(l) + CO2(g)

Carbonic acid, H2CO3, is an unstable substance. It readily decomposes to form ______ and ________ H2CO3(aq) ---> _____ +______

fewer

Cations have _______ electrons than protons. To write their electron configurations, we remove valence electrons from the atom's electron configuration.

remove

Cations have fewer electrons than protons. To write their electron configurations, we _______ valence electrons from the atom's electron configuration.

a. double displacement b. single displacement c. combination d. decomposition

Classify each of the following as a decomposition, combination, single-displacement, or double-displacement reaction. (a) Na2S(aq) + 2HCl(aq) ---> H2S(g) + 2NaCl(aq) (b) H2(g) + CuO(s) ----> Cu(s) + H2O(g) (c) 2Fe(s) + 3Cl2(g) ----> 2FeCl3(s) (d) 2Na2O2(s) ----> 2Na2O(s) + O2(g)

another compound 2CO2(g)

Combination Reactions A compound and an element can combine to form ________. 2CO(g) +O2(g) ---> ______

a molecular compound. CO2(g)

Combination Reactions Nonmetals can react with other nonmetals to form ________ C(s) + O2(g) ----> _____

a new compound.

Combination Reactions Two compounds may react to form _______ CaO(s) + CO2(g) ----> CaCO3(s)

an ionic compound. 2NaCl(s)

Combination Reactions: Metals can react with nonmetals to form _________ 2Na(s) + Cl2(g) --->_______

insoluble

Compounds that are _______ in water, such as AgCl(s), do not break apart into ions.

single-displacement reaction Mg(s) + 2HCl(aq) ---> MgCl2(aq) + H2(g)

Consider a ____________ reaction between magnesium metal and aqueous hydrochloric acid: _________----> _______

1s^2 2s^2 2p^2 C 1s^2 2s^2 2p^2

Consider the arrangement of electrons in a carbon atom, as shown by its orbital diagram. The lowest-energy sublevel, 1s, contains two electrons. This is represented as__________ The next higher-energy sublevel, 2s, also contains two electrons: _______ We write the electron configuration to show the total number of electrons in the 2p sublevel: Combining the sublevels, we get the electron configuration for carbon:_________

a yellow solid of lead(II) iodide, potassium acetate PbI2(s) + 2KCH3CO2(aq)

Double-Displacement Reactions: Jennifer mixed a solution of lead(II) acetate with a solution of potassium iodide and formed __________, leaving _______ in solution: Pb(CH3CO2)2(aq) + 2KI(aq) -----> _______+_______

before ( because the 4s sublevel is lower in energy than the 3d)

Electrons fill the 4s orbital _____ filling the 3d orbitals

last-occupied sublevel and principal energy level

Elements in the same group have the same number of electrons in their ________ and _______

orbitals

Erwin Schrödinger's new model of the atom describes electrons as occupying __________, not orbits.

2C2H6(g) + 7O2(g) --> 6H2O(g) + 4CO2(g)

Ethane, C2H6, is a gaseous fuel that can be burned with oxygen. Balance the following skeletal equation for this reaction: C2H6(g) + O2(g)----> CO2(g) + H2O(g)

MM of A, mole ratio, MM of B

Grams A --______-->Moles of A---_____-->Moles B---____-->Grams B

a greater mass, greater specific heat, or greater temperature change.

Greater heat could arise from a ___, _____, or ____

hotter--> colder; thermal equilibrium.

Heat is always transferred from the ______ to the _____ object. When two objects that are in contact become equal in temperature, they have reached a state of ____________

s

Helium is an ____ block element.

We can use the activity series shown in Figure 5.21 The more active metal displaces the less active metal from its ionic compound, but a less active metal cannot displace a more active metal from its ionic compound.

How can we predict if a single-displacement reaction will occur when a metal is added to an ionic compound in solution?

10.0 cal or 41.8 J.

How much energy will increase the temperature of a 1.00-g sample by 10.0°C? You need 10.0 times as much heat for a 10.0°C increase than for a 1.00°C increase; you need _____ cal or ____ J.

separate

Hund's rule follows that electrons should be found in ______ orbitals if no energy is required to get there.

negatively charged electrons repel each other

Hund's rule is a consequence of the fact that _____________.

unpaired electrons.

Hund's rule states that electrons are distributed into orbitals of identical energy (same sublevel) in such a way as to give the maximum number of ________

anhydrous compounds CaSO4(s) + 2H2O(g)

Hydrates—compounds that contain water molecules—lose water to form __________ , compounds free of molecular water. One example is hydrated calcium sulfate. It can be dehydrated by heating to form a powder: CaSO4 · 2H2O(s) ---heat---> ____ +_____

1.52 mol H2O

If 1.14 mol of CO2 was formed by the combustion of C3H8, how many moles of H2O were also formed?

the ion of the metal lowest in the activity series is most likely to be converted to its element form

If a piece of metal is placed in a solution containing two different metal ions, which metal ion will be more likely to convert to its element form?

precipitation

If a possible product is insoluble, a ____ reaction should occur. (We can predict whether such a compound will form by consulting the solubility rules, some of which are listed in Table 5.4.)

No, the double displacement would precipitate both cations and both anions leaving no ions in solution

If a precipitation reaction forms two insoluble products, are there any spectator ions?

no, although the atoms are balanced, a correctly balanced equation should have the lowest possible whole number coefficients

If all the coefficients in a chemical equation are divisible by 2, is the equation properly balanced?

p or f block

If an atom has a partially-filled p or f subshell outside the noble-gas core, the corresponding element lies in the ____ or ____ block, respectively

no this is a single displacement reaction

If an element reacts with a compound to form a new compound and a different element, would this be a combination reaction?

last filled subshell

If the atom has no partially-filled subshells outside the noble-gas core, the ________ tells you the block in which the corresponding element lies.

limiting reactant ; excess

If the ratio of H2 to O2 molecules mixed together is not exactly 2H2 molecules/ 1 O2 molecule, then one reactant is the _________ and the other is in _____.

limiting reactant

If the reactants mixed together are not present in the exact mole ratio, then we will have too much of one reactant and not enough of another. One reactant reacts completely, and some of the other is left unreacted. The reactant that reacts completely is called the _______________

if the mass of the limiting reactant Na is doubled, the theoretical yield of H2 would also double to 0.50 mol. because the ratio of actual yield to theoretical yield is constant with the same percent yield, we would expect the actual yield of H2 to also double from 0.21 mol to 0.42 mol.

If we doubled the amounts of both reactants, predict the moles of H2 produced assuming the same percent yield you just calculated. moles H2= 0.50 mol Na x (1 mol H2/2 mol Na) = 0.25 mol H2 (theoretical yield) percent yield= (0.21 mol H2/ 0.25 mol H2) x 100% = 84%

five; lie along a specified plane; p orbital with a donut shape around its center.

there are ____ d orbitals in a d sublevel. Most have four lobes that __________ in space. One looks like a ________ with a _____

precipitation, gas formation, and acid-base neutralization reactions

three classes of double-displacement reactions: _____, ______, and _____

single-displacement

In a ______ reaction, a free element displaces another element from a compound to produce a different compound and a different free element.

combination (synthesis)

In a _______ reaction (also called ______), two substances react to produce a single compound. The reactants can be two elements, an element and a compound, or two compounds.

endothermic

In an _______ reaction, the products have more potential energy than the reactants.

what is left after water is removed

Oxoacids decompose in a similar way to form nonmetal oxides and water. Other compounds that contain the components of water frequently decompose with the elimination of water. The other product is ______________________

endothermic

Physical changes, such as phase changes, can also be endothermic or exothermic. Sweating is a natural process that helps cool our bodies when the water in sweat evaporates. Evaporation is an __________ process, so it absorbs heat from our skin. Our skin cools, helping to maintain normal body temperature.

lime; (calcium carbonate); decomposition

Portland cement has calcium oxide (_____) as one of its ingredients. The calcium oxide is made from limestone (_______) by _______ in large kilns at about 1900°C

2KClO3(s) ---heat--> 2KCl(s) + 3O2(g)

Potassium chlorate is a white solid that decomposes when heated, forming solid potassium chloride and oxygen gas. Balance the equation that represents the reaction.

arrangement

Products are different from reactants in the _______ of their component atoms.

C3H8 C3H8(g) + 5O2(g) ---> 3CO2(g) + 4H2O(g)

Propane, _____, is a hydrocarbon used as a fuel for barbecue grills. The combustion of propane is described by the following equation: ____ + ____ ---> ____ + ____

142 mol

Pure methanol is used as a fuel for race cars in the Indy Racing League and in the Championship Auto Racing Teams. It is used because methanol fires are easier to put out with water than the fires of most other fuels. The balanced equation for the combustion of methanol is 2CH3OH(l) + 3O2(g) ---> 2CO2(g) + 4H2O(g) Given that 1.00 gal of methanol contains 94.5 mol, how many moles of oxygen gas will react with 1.00 gal of methanol?

oxidation-reduction

Reactions in which the ionic charges change are called ___________ reactions. In the decomposition of HgO, the charge of mercury changes from 2+ to 0 when Hg(l) is formed. The charge of oxygen changes from 2− to 0 when O2(g) is formed.

limiting reactant

Remember that we must use the amount of ________ to calculate the moles of the product:

soluble NO3-, CH3CO2-

Rules Used to Predict the Solubility of Ionic Compounds All nitrates and acetates are _______. Ions: ___,____,___

insoluble (CO3^2-, PO4^3-, SO3^2-, SiO3^2-) Na+, K+, and NH4+

Rules Used to Predict the Solubility of Ionic Compounds Most carbonates, phosphates, sulfites, and silicates are _______. Exceptions are compounds of ____,____,____

soluble; (Cl−, Br−, I−) AgX, Hg2X2, PbX2, and HgI2. (X = Cl, Br, or I.)

Rules Used to Predict the Solubility of Ionic Compounds Most chlorides, bromides, and iodides are _____(Ex._____). Exceptions are _____,___,____,____

four ( two s electrons and two p electrons)

Silicon, for example, is in group IVA (14); the Roman numeral IV corresponds to ______ valence electrons.

soluble

Sodium chloride is ________ according to the first solubility rule

more; less; less, more would not ; would

The _____ active metal displaces the ______ active metal from its ionic compound, but a _____ active metal cannot displace a _____ active metal from its ionic compound. Thus, tin or copper ______ displace iron from FeCl2, and magnesium _____

alkali metals; vigor

The __________ all react with water to form the corresponding alkali metal hydroxide and hydrogen gas. The pattern of rearrangement is the same for all of these reactions. They differ only in their _____.

mass

The actual yield and theoretical yield can be expressed in any units, as long as those units are the same. Usually yields are reported in ______ units, but yields in units of moles or molecules are acceptable.

specific heat.

The amount of heat that must be added to 1 g of a substance to raise its temperature by 1°C is a unique property of that substance, called its ________

(a) endothermic reaction (b) 133 kJ

The balanced equation for the combination reaction of hydrogen gas and solid iodine is H2(g) + I2(s) ----> 2HI(g) The heat change q for this reaction is +53.00 kJ per mole of I2 that reacts. (a )Is this reaction endothermic or exothermic? (b) What is the heat change when 2.50 mol of I2 reacts?

4A; metalloid (Ge) and a metal (Sn).

The p-block elements with two p electrons are all in Group _____. In this case, the full d subshell and the lack of f electrons is actually enough to tell you these elements lie in Periods 4 or 5, and the Group 4A elements in these periods are a_____ or _____

s and p orbitals called the 2s and 2p orbitals; 2s and 2p orbitals

The second principal energy level (n = 2) consists of _______ orbitals called the _____________.

activity series

We can use an _______, a list of the metals in order of their reactivity, to predict which metals react with water or acids

a molecular equation

a _________ equation represents the substances as if they existed as molecules (or formula units) in solution rather than dissociated into ions.

decomposition reaction

a chemical reaction in which a substance breaks down into simpler compounds or elements (of which it is composed)

electron configuration

a description of the distribution of electrons in atomic orbitals or sublevels.

law of conservation of energy

a law stating that energy can be converted from one form to another, or transferred, but it cannot be created or destroyed.

an isoelectronic series

a series of ions with the same number of electrons= ___________

water soluble; insoluble

according to the solubility rules in Table 5.4, most sulfate compounds, sodium compounds, and chloride compounds are water ______________. An exception is barium sulfate, which is ______.

potassium; explosive

all of the alkali metals react with water; what differs is the vigor of the reaction. With the ______ reaction, the hydrogen always catches fire and for the alkali metals below it in the periodic table, the reaction with water is ____.

increases

atomic size ________ as you go down a group

neutral, charged

atoms =_____ ions =_______

BaCl2(aq) + Na2SO4(aq) ---> BaSO4(s) + 2NaCl(aq)

balance this equation BaCl2(aq) + Na2SO4(aq) ----> BaSO4(s) + NaCl(aq)

1s orbital

helium's ground-state orbital diagram consists of two electrons in the_______

1 element and 1 compound

if the reactant is 1 element and 1 compound, the product can be ________

2 compounds

if the reactant is 2 compounds, the product can be ________

1 compound

if the reactant is 2 elements or compounds, the product can be ________

must equal; gained or lost

law of conservation of mass states that the mass of the reactants __________ the mass of the products. mass is not ____ or ______.

8SO2(g)

nonmetal combustion: S8(s) +8O2(g) ---> _____

ZnCl2(s)

react 2 elements to form compound: Zn(s) + Cl2(g) ----> _____

CaSO3(s)

reaction between two compounds, combine to form new compound: CaO(s) + SO2(g) --->_____

detonation velocity

that a relatively small amount of energy is released when TNT (trinitrotoluene) burns. Other fuels release much more energy per mole or per gram. Is this surprising? The explosive nature of TNT has to do with its _______ The rate at which the reaction occurs is greater than for other fuels.

the Pauli exclusion principle

the ________ states that a maximum of two electrons can occupy each orbital, and they must have opposite spins.

equals

the principal energy level number is the same as the period number for the s and p sublevels. Now we know that the valence electrons occupy the highest-energy s and p sublevels. This tells us that the period number of the element ________ the valence level number.

percent yield

the ratio of the amount of product actually formed in a reaction to what is predicted by stoichiometry, multiplied by 100%

We use the limiting reactant Cl2 because it reacts completely. We multiply the moles of limiting reactant Cl2 by the mole ratio of NaCl to Cl2 to determine the moles of NaCl that can form: moles of NaCl= 0.20 mol Cl2 x (2 mol NaCl/ 1 mol Cl2) = 0.40 mol NaCl

the reaction of sodium metal and chlorine gas: 2 Na(s) + Cl2(g) ---> 2NaCl(s) Suppose we mix 0.50 mol Na with 0.20 mol Cl2. We can determine how much NaCl should form by doing a mole-mole calculation. Which reactant do we use?

develop lose anions

when copper metal reacts with aqueous silver nitrate to form silver metal and aqueous copper(II) nitrate, the atoms on the surface of the copper metal ______ a positive charge by losing electrons and go into solution as copper(II) ions. Silver ions in solution, upon contacting the piece of copper metal, ______ their positive charge by gaining electrons to form silver atoms that stick to the copper's surface. The _________ are not involved in the reaction and remain unchanged in the solution.

ionic; unit

when part of a reactant is unchanged in the products it usually arises with ______ compounds in which the anion is an oxoanion or some other polyatomic anion. If the anion is unchanged in the products, it can be treated as a _____ instead of as a collection of atoms that must be balanced individually.

balanced

when writing a chemical equation it must be a ________ equation, where the number of atoms of each element is the same in the products as in the reactants.

Mn 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^5

write the electron configuration for manganese

AgNO3 is the limiting reactant; 1.0mol

2 AgNO3(aq) + MgCl2(aq) ---> 2AgCl(s) + Mg(NO3)2(aq) Suppose we mix 1.0 mol of silver nitrate with 1.0 mol of magnesium chloride. Identify the limiting reactant and the number of moles of solid AgCl that can form.

liquid mercury metal and oxygen gas (Gaseous oxygen fills the container, and droplets of liquid mercury settle on its cooler parts)

A few binary compounds decompose to their constituent elements upon heating. For example, when red solid mercury(II) oxide, HgO, is heated, it slowly decomposes into _______ and _____

4.184 J

A joule is smaller than a calorie: 4.184 J = 1 cal

orbital

An ______ is a three-dimensional region in space where the electron is likely to be found, not a circular pathway.

electron paramagnetic resonance (EPR) or electron spin resonance (ESR)

An electron behaves as though it were spinning on its axis, like a bicycle wheel. It can spin in only two directions, just like a bicycle wheel can spin only forward or backward. Two electrons in a given orbital must have opposite spin directions. This spin property of electrons can be detected in a magnetic field, using a technique known as _________ or ____________

core electron, or inner electron.

An electron in a principal energy level below the valence level is called a _______ (or ______)

reactants are Fe(s) and CuSO4 (aq), products are Cu(s) and FeSO4 (aq)

Antonio placed a piece of iron in a solution of copper(II) sulfate. He obtained a deposit of copper metal and a solution containing iron(II) sulfate. Identify the reactants and products in this chemical reaction.

C2H2(g) + O2(g) --> CO2(g) + H2O(g) balanced: 2C2H2(g) + 5O2(g) ---> 4CO2(g) + 2H2O(g)

Antonio uses an oxyacetylene torch to cut some pieces of metal. The heat from the torch comes from the combustion of acetylene, C2H2(g). Write a skeleton and a balanced equation for the reaction.

the 3s, 3p, and 3d sublevels

At the third principal energy level (n = 3), three sublevels are available: the ___,____, and ___sublevels.

increases

Atomic size ________________ down a group and from right to left in a period.

p block. 3A; 6 or 7, and all Group 3A elements in these periods are metals.

Atoms with electron configurations that match the third pattern [G] ns^2 of^14 md^10 np^1 have a partially-filled p subshell, so the corresponding elements are in the _____ block. These block elements with one p electron are all in Group _____ In this case, the full f subshell is actually enough to tell you these elements lie in Periods____ or ____and all of these Group elements in these periods are ______.

d block

Atoms with partially filled d sub-shells correspond to elements in the ___ block if they have no f electrons outside the noble-gas core, or a completely filled f sub-shell.

s block

Atoms with partially filled s sub-shells correspond to elements in the____ block if they have no d electrons outside the noble-gas core.

d subshell

Be careful: keep in mind that if the atom has s and d electrons (or s, d, and f electrons) outside the noble-gas core, the ___ subshell is the last subshell to be filled, even though the s subshell may be listed last

two electrons in the 1s orbital, two electrons in the 2s orbital, and one electron in one of the 2p orbitals.

Boron, with five electrons, has an orbital diagram with _____ electrons in the ______ orbital, _____ electrons in the _____ orbital, and _____ electron in _______

molecular: AgNO3(aq) + KBr(aq) --> AgBr(s) + KNO3(aq) ionic: Ag+(aq) + NO3-(aq) + K+(aq) + Br-(aq)---> AgBr(s) + K+(aq) + NO3-(aq) net ionic: Ag+(aq) + Br-(aq) --> AgBr(s)

Consider the reaction between colorless aqueous solutions of silver nitrate, AgNO3, and potassium bromide, KBr, which gives a pale yellow precipitate and a colorless solution. The precipitate is used extensively in photographic films and papers. Identify the precipitate and write molecular, ionic, and net ionic equations for the reaction.

diatomic; slowly; vigorous, even explosive

Consider the reaction of hydrogen gas with oxygen gas. Hydrogen and oxygen both occur naturally as _______ molecules. If they mix, they react _______; but if ignited, the reaction is _______, even ______.

the elements

Decomposition Reactions That Occur When Compounds Are Heated: Oxides and halides of the metals Au, Pt, and Hg decompose to ________.

abbreviated electron configurations.

For elements with lengthy electron configurations, chemists often use ________________

CaO(s) + H2O(l) ---> Ca(OH)2(aq)

For example, the equation for the reaction of calcium oxide with water is:

Group IVA (14)

If an unknown main-group element is known to have four valence electrons, identify the group of elements that it's in.

solid, a gas, or a stable molecular compound

In each case of double displacement, reactant ions are removed from the solution by forming a new substance—either a ____,_____, or ____.

Cd(NO3)2(aq) + Na2S(aq) ---> CdS(s) + 2NaNO3(aq)

Jennifer mixes solutions of cadmium(II) nitrate and sodium sulfide and obtains an orange precipitate that is the pigment cadmium orange. Identify the precipitate, and write a balanced equation for the reaction she carried out.

soluble

Metal ions of group IA (1) always form _______ compounds, so they are always spectator ions in double-displacement reactions.

d sublevel (nd^1); 10 electrons (nd^10).

Most of the time, the transition metals follow a similar pattern as the main-group elements in the s and p blocks. For example, the group IIIB (3) transition metals (Sc and Y) have one electron in the last-occupied ________ sublevel. The group IIB (12) transition metals (Zn and Cd) have _____ electrons (____).

upper-right corner; noble gases; fluorine, F2.

Nonmetals become more reactive the closer they are to the ________ of the periodic table, ignoring the______ The most reactive nonmetal is _______

electrolytes; insoluble compound or a stable molecular compound.

Not all combinations of two compounds can undergo a double-displacement reaction. Consider aqueous solutions of the compounds potassium chloride, KCl, and nitric acid, HNO3, for example. Because they are _____, they exist as free ions: K+(aq), Cl−(aq), H+(aq), and (aq). Upon mixing, we see no sign of a reaction because no combination of the component ions can form either an _____ or a _____

endothermic

Not all reactions release energy. Some require a continuous energy input. A reaction (chemical change) that absorbs energy/heat from the surroundings is an _________ reaction.

1g; 1°C.

One calorie is the amount of heat energy needed to raise the temperature of ____ g of water by ____°C.

smaller; larger; extend farther

Orbitals at lower-energy levels are ______. Orbitals at the higher-energy levels are _________ and ________ from the nucleus.

molecular

Pb(NO3)2(aq) + K2CrO4(aq) ---> PbCrO4(s) + 2KNO3(aq) this is an example of a ________ equation

2CH3OH(l) + 3O2(g) --> 2CO2(g) + 4H2O(g)

Shellac, used as a transparent coating on wood and other materials, is a suspension of a tree sap (resin) in methanol, CH3OH(l). The mixture is highly combustible. Write an equation to describe the combustion of methanol.

exothermic

Since all combustion reactions are ___________, the reaction releases heat that the water absorbs.

3A, 3

Since gallium belongs to Group _____, there are ____ valence electrons in a neutral Ga atom.

steam

Some metals, such as magnesium, do not react with cold water, but react slowly with ______

Mg(OH)2(aq) + H2(g)

Some metals, such as magnesium, do not react with cold water, but react slowly with steam: Mg(s) + 2H2O(g) --heat--> ________

unstable

Sometimes insoluble gases do not form directly from a double-displacement reaction-- instead they form when an ________ product of a double-displacement reaction decomposes.

system

Sometimes, we are interested not in an object, but in a process such as a chemical reaction. We call whatever we are interested in—whether an object or a process—the ___________.

joules per gram per degree Celsius [J/(g °C)] or calories per gram per degree Celsius [cal/(g °C)].

Specific heat values are expressed in units of __________ or _________

100 molecules of C3H8 will combine with 500 molecules of O2 which will produce 300 molecules of CO2 and 400 molecules of H2O 6.022×10^23 molecules C3H8 will combine with 3.011x10^24 molecules O2 which will produce 1.8066x10^24 molecules of CO2 and 2.4088x10^24 molecules of H2O

Suppose 100 molecules of C3H8 react, or suppose 6.022 × 10^23 molecules (a mole of molecules) react. How many O2 molecules will combine with each of these quantities? How many molecules of CO2 and H2O should form in each case? Compare your answers to those shown in Table 6.1.

percent yield = (26.8g/50.0g) x 100% = 53.6%

Suppose the reaction of aluminum metal and liquid bromine described in Example 6.7 produced only 26.8 g AlBr3. What is the percent yield? Since we calculated the amount of AlBr3 that should form as 50.0 g, we know the theoretical yield. The percent yield is the ratio of the actual yield to the theoretical yield multiplied by 100:

barium sulfate, BaSO4, and sodium chloride, NaCl; barium sulfate.

Suppose we mix colorless, aqueous solutions of barium chloride and sodium sulfate. As shown in Figure 5.26, this reaction produces a white precipitate, so we know a reaction occurs. To identify the precipitate, we determine which product of double displacement is insoluble in water. After exchanging the cations and anions present in the reactants, we determine that the products are ______ and ______To determine which of these compounds is the precipitate, we consult the solubility rules. the precipitate is the insoluble product ___________

mole ratio: 3 mol Co2 / 1 mol C3H8 27.6 mol CO2

Suppose we want to know the amount of CO2 that will be produced when 9.21 mol of C3H8 reacts. What mole ratio do we use? determine the moles of CO2 produced when 9.21 mol C3H8 reacts:

larger

The 2s orbital is like the 1s orbital, but it is ________.

a single 2s ; three 2p

The 2s sublevel consists of _______ orbital, and the 2p sublevel consists of ______ orbitals.

combustion

The burning of a fuel, such as logs in a fireplace or methane in a gas stove, is a common ______ reaction. these reactions are also used to heat kilns for firing pottery.

1000

The calorie used in chemistry should not be confused with the Calorie used by nutritionists, which is actually a kilocalorie (kcal), or ______ cal.

exist

The coefficients are whole numbers because parts or fractions of atoms or molecules do not ________.

less; less

The combustion of ethanol releases ______ energy than the combustion of the hydrocarbons, like octane, that are found in gasoline. Thus, ethanol, although being used as a gasoline additive or replacement, is a ____ efficient fuel than gasoline. On the other hand, fuels derived from plant materials are renewable, consistent with the principles of green chemistry.

s

The group IA (1) and IIA (2) elements and the element _______ are in the ____ block.

last-occupied p sublevel; np^6

The noble gases, group VIIIA (18)—each with one more electron than the halogen it follows—have six electrons in the _____________ sublevel. Each ends in ________

1.000 cal/(g °C) or 4.184 J/(g °C).

The specific heat of liquid water ism_______ cal/(g °C) or ______ J/(g °C).

15, the number of electrons in a phosphorus atom.

The superscripts in the electron configuration for phosphorus should add to ______

the number of electrons in an atom of the element (its atomic number)

The superscripts in the electron configuration should add to _________

group number

The________ of each element is the number of valence electrons in each atom.

double-displacement reaction

Thus, a ________________ should occur if an insoluble gas would be formed.

(a) Si 1s^2 2s^2 2p^6 3s^2 3p^2 (b) Zr 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^2 (c) Br 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^5

Use a periodic table to write the electron configurations for the following elements. (a)Si (b)Zr (c)Br

magnesium metal; metal; acid coefficients 1 mol Mg/ 2 mol HCl

When there is excess magnesium, we see the _______ remaining with the solution. When there is excess hydrochloric acid, no _____ remains with the product solution, which also contains excess ______. If we do not want any unreacted magnesium or hydrochloric acid left over, we should mix the reactants in the proper quantities so that their mole ratio is the same as that shown by the _______ in the balanced equation: ___mol of Mg / ___mol of HCl

multiply

When we convert from moles to grams, we always ________ by the molar mass.

acids;

_______ are compounds that release hydrogen ions

Gas-Formation Reactions

_________________Reactions occur in some double-displacement reactions when the formation of an insoluble (or only slightly soluble) gas provides the driving force for a reaction

metals

all d and f block elements are ________.

2Hg(l) +O2(g)

compound broken down into elements: 2HgO(s) --->____ + _____

NH3(g) + HCl(g)

compound broken down into smaller molecules: NH4Cl(s) --->___ + _____

anhydrous compounds

compounds free of molecular water.

Hydrates

compounds that contain water molecules

highly reactive metal

consider a common type of single-displacement reaction, one in which a _________ displaces hydrogen from water.

calcium hydroxide and hydrogen gas; only one H atom from each H2O molecule:

consider a common type of single-displacement reaction, one in which a highly reactive metal displaces hydrogen from water. For example, calcium reacts with cold water to form _____ and _____. Note in the equation for the reaction that calcium displaces __________________ : Ca(s) +2H2O(l) ---> Ca(OH)2(aq) + H2(g)

monatomic; diatomic

consider the case in which we have just one reactant- we probably have to heat the substance for something to happen. If we have an element, what could result? A _____ element can't do anything because there is no way to rearrange a single atom. A _____ element might break down into its component atoms

mass of reactants = mass of products Mass Na + mass Cl2 = mass NaCl 9.20 g Na + 14.2 g Cl2 = 23.4 g NaCl

consider the combination reaction of sodium metal and chlorine gas to form sodium chloride: 2Na(s) + Cl2(g) ----> 2NaCl(s) Suppose we have 9.20 g of sodium metal and 14.2 g Cl2 what is the mass of NaCl ?

23.4 g NaCl

consider the combination reaction of sodium metal and chlorine gas to form sodium chloride: 2Na(s) + Cl2(g) ----> 2NaCl(s) Suppose we have 9.20 g of sodium metal. How many grams of NaCl should form?

14.2 g Cl2

consider the combination reaction of sodium metal and chlorine gas to form sodium chloride: 2Na(s) + Cl2(g) ----> 2NaCl(s) Suppose we have 9.20 g of sodium metal. How many grams of chlorine gas should react with this amount of sodium in this reaction?

9

food component: kcal/g (Cal/g) = _____fats

4

food component: carbohydrates kcal/g (Cal/g) = _____

4

food component: proteins kcal/g (Cal/g) = _____

one electron in the last-occupied sublevel, the s sublevel; ns^1, where n is the principal energy level.

group IA (1) elements all have __________ in the ______ sublevel. Each ends in ________

25CO2(g) + 26H2O(g)

hydrocarbon combustion: C25H52(s) + 38O2(g) ---> ____ +____

CO2(g) + 2H2O(g)

hydrocarbon combustion: CH4(g) + 2O2(g) ---> _____ + _____

HCl(aq)

hydrochloric acid = ______ chemical formula

AgCl(s) + KNO3(aq)

ionic compound reactant is composed of a polyatomic ion: AgNO3(aq) + KCl(aq) ----> ____ + _____

right, up

ionization energy increases as you move _____ or to the _____ on periodic table

NaOH(aq)

sodium hydroxide = ______ chemical formula

increases

the ionic radii for ions of the main-group elements--> Note the trend down a group and for ions that are isoelectronic the ionic radii ______

smaller

the more pull we have from the protons, the ________ our atom is going to be overall

aluminum and iron(III) oxide single-displacement

the thermite reaction is between _____ and _____ (and it is a ____ reaction)

2NaCl(aq) + CuS(s)

two compounds rearrange to form two new compounds: CuCl2(aq) + Na2S(aq) ----> ____ + ____

law of conservation of mass

we can use the law of _____________ to determine the mass of one substance in a reaction if it is the only unknown mass in the reaction.

higher; higher; 3d

within a given principal energy level, the p orbitals are ________ in energy than the s orbitals, and the d orbitals are _____ in energy than the p orbitals. The _____ orbitals are so high that they are slightly higher in energy than the 4s orbitals.

p block; p electrons; period 1; 1s^2 (period 1) 2s^2 2p^6 (period 2) 3s^2 3p^3 (period 3) P 1s^2 2s^2 2p^6 3s^2 3p^3

write the electron configuration for phosphorus using the periodic table. Phosphorus is a main-group element in the ____ block, so we expect its highest-energy electrons to be ______ we start in period _____ there is only an s block so we write ________ In the next row, period 2, there are two columns in the s block and six columns in the p block so we write _____ In the third row, period 3, there are two columns in the s block. In the p block, we fill in only three electrons because phosphorus is in the third column of the p block so we write _____ Combining the configurations from each period, we get the electron configuration for phosphorus ______

(a) 1s^2 2s^2 2p^6 3s^1 (b) 1s^2 2s^2 2p^6 3s^2 3p^6 (c) 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^5

write the electron configurations for the following: (a)Na (b)Ar (c)Br

more; less; cold water to release H2 gas; steam to release H2 gas acids hydrogen as H2 gas

A _____ active element displaces a _____ active element from its compounds. The most active elements, found at the top of the activity series, react with _____ to release _____ The next most active elements react with ______ to release _______. All the elements more active than hydrogen in the series react with _____. None of the elements less active than hydrogen displace ____ as ____ from any compound. Note that some of the less active metals are commonly found in coins and jewelry.

(a) The temperature of the water decreased, so the temperature of the brick must have increased. Since they both have the same temperature at thermal equilibrium, the brick must have started out at a lower temperature than the initial temperature of the water. (b) We don't know the mass or temperature of the brick, so we can't determine the heat change q for the brick directly. However, we do know the mass, specific heat, and temperature change of the water. The water is the brick's surroundings, so if we determine the heat change of the water, we can use the law of conservation of energy to determine the heat change of the brick. To determine the heat change of the water, we use the equation: q(water) = m x c x ΔT ΔT= 19.4 - 25.0 = -5.6 °C mass in grams = 5.000 kg x (1000g/1 kg) = 5.000 x 10^3 g q (water)= 5.000 x 10^3 g x 4.184 J/g°C x (-5.6°C) = -1.2 x 10^5 J The negative value of qwater means that the water released heat. From the law of conservation of energy, we know that the brick absorbed the same amount of heat that the water released. The heat change of the brick plus the heat change of the water must sum to zero. This means that the heat change of the water is equal and opposite in sign to the heat change of the brick: q (brick) + q(water) = 0 q (brick) = -q(water) = +1.2 x 10^5 J

A brick is placed in an insulated calorimeter containing 5.000 kg of water. The temperature of the water decreases from 25.0°C to 19.4°C when thermal equilibrium is reached. (a) Was the initial temperature of the brick greater than or less than the initial temperature of the water? Explain. (b) What is the heat change q of the brick?

lost Ca2+ 1s^2 2s^2 2p^6 3s^2 3p^6

A calcium atom has the following electron configuration: Ca 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 When a Ca2+ ion forms, two electrons are _____ from the valence 4s sublevel. We write the electron configuration for a Ca2+ ion as ______________

A chemical reaction is the conversion of one substance or set of substances into another.

A chemical reaction is the conversion of one substance or set of substances into another.

gained Cl− 1s^2 2s^2 2p^6 3s^2 3p^6

A chlorine atom has the following electron configuration: Cl 1s^2 2s^2 2p^6 3s^2 3p^5 When a Cl− ion forms from a chlorine atom, one electron is ______ from the valence 3p sublevel. The electron configuration for a Cl− ion is:: ___________________

HCl(aq) + NaOH(aq) ---> NaCl(aq) + H2O(l)

A common laboratory example of an acid-base neutralization is the reaction between hydrochloric acid and sodium hydroxide: ___ +____ ----> ____ + ____

bomb calorimeter

A common way to determine the amount of heat released by combustion of a fuel such as ethanol is to use a special type of calorimeter called a ________

one exists with a higher atom:atom ratio

A compound and an element may combine to form another compound if __________

mole ratios

A convenient way to relate the moles of a reactant or a product to other reactants or products is to use _______

orbital diagram.

A convenient way to show the distribution of sublevels and orbitals in an atom is with an _______

a greater mass transfers more heat

A drop of boiling water spilled on your hand stings, but a cup of boiling water spilled on your hand burns. What factor explains the difference?

1000

A kilojoule (kJ), or _______ J, is approximately the amount of energy that is emitted when a wooden kitchen match burns completely.

not react; more active metal will displace ions of the less active metal from solution

A metal placed in a solution containing its own ions will _______. Thus, we must consider whether iron metal will displace zinc ions from solution or whether zinc metal will displace iron(II) ions from FeCl2 in solution. To determine which reaction will occur, we consult the activity series. The ________ will displace ions of the ________ from solution

lose water

A number of compounds that contain water or the components of water—hydrates, hydroxides, and oxoacids—____________ when heated.

Calories (kilocalories)

A nutritional label gives the energy content in ______ (or ______) per serving.

excess

A reactant that does not react completely is in ___________.

exothermic

A reaction (chemical change) that releases energy/heat is called an _______ reaction.

(a) greater, the rise in temperature of the water indicates that the alloy was hotter (b) -3400 J

A sample of a metal alloy is heated and then placed in 125.0 g of water held in a calorimeter at 22.5°C. The final temperature of the water is 29.0°C. Assume heat exchange only occurs between the water and the alloy. (a) Was the initial temperature of the alloy greater than or less than the initial temperature of the water? Explain. (b) What is the heat change of the alloy?

q = m x c x ΔT q = 7.5 x 10^4 g x 0.49 J/g°C x 25 °C = 7.5 x 10^4 x 0.49 J x 25 = 9.2 x 10^5 J oor 9.2 x 10^2 kJ q is positive, which means that the rocks have absorbed heat If more rocks were added, the amount of heat absorbed would increase because there would be a greater mass.

A simple solar energy heater is a glass-topped box containing rocks. Sunlight heats the rocks during the day, and air is blown over them at night to heat a house. The box contains 7.5 × 10^4 g of rocks, which have a specific heat of 0.49 J/(g °C). How much additional heat can the rocks store when they warm from a nighttime temperature of 18°C (65°F) to a daytime temperature of 43°C (110°F)? If more rocks were added to the solar heater, would the amount of heat absorbed change?

figure-eight or dumbbell; three

A single p orbital, has a ________ shape. In their respective principal energy levels, p orbitals always come in sets of _____.

metal hydroxide and oxygen gas

Alkaline earth metals react in a similar way, producing a ____ and _______

nonmetals; metals or metalloids; metals, nonmetals and metalloids.

All p block elements with five or six p electrons (in Groups 7A and 8A) are ______ All p block elements with only one p electron (in Group 3A) are ____ or ______. The remaining groups of the p block contain ____,____,____

metals

All s block elements except hydrogen and helium are _______.

oxidation-reduction reactions

All single-displacement reactions are _________ reactions.

hydrogen

All the elements more active than ______ in the series react with acids

single-displacement; no; more

Although a _________ reaction occurs when a piece of copper metal is placed in a solution of silver nitrate, __________ reaction occurs when a piece of silver is placed in a solution of copper(II) nitrate. Copper is ______ active than silver.

Density = mass/ volume mass = density x volume

Although chemicals are often measured by mass, some substances are more conveniently measured by volume. If the substance is pure and the density is known, then the mass can be determined from the density and volume using the relationship you learned in Chapter 1: Density= ____ so mass= ____

molecular: BaCl2(aq) + Na2SO4(aq) ---> BaSO4(s) + 2NaCl(aq) ionic: Ba2+(aq) + 2Cl-(aq) + 2Na+(aq) + SO4^2-(aq)--> BaSO4(s) + 2Na+(aq) + 2Cl-(aq) net ionic: Ba2+(aq) + SO4^2-(aq) --> BaSO4(s)

Although soluble barium compounds are toxic in body fluids, barium sulfate is safely used as a contrast agent for X-ray imaging the gastrointestinal (GI) tract because it is insoluble in water. After a slurry of the compound is ingested, the GI tract becomes visible on an X-ray. Barium sulfate can be prepared by mixing solutions of barium chloride and sodium sulfate. Write balanced molecular, ionic, and net ionic equations for the reaction.

aluminum bromide

Aluminum reacts with bromine rather spectacularly to produce __________

aluminum metal; iron ion ; Fe2O3--> Al2O3 2Al(s) + Fe2O3(s) ---> Al2O3(s) + 2Fe(l)

An example is the thermite reaction between aluminum and iron(III) oxide, used in the production of iron metal for welding: In this single-displacement reaction, ________ displaces _____ from ________, producing the new compound _______ and free iron metal: ______+________-----> ____+_____

downhill; uphill

An exothermic reaction is thought of as being "_______" because the products contain less stored energy than the reactants. An endothermic reaction is thought of as being "______" because the products contain more potential energy.

ionic compound; cation; anion

An important type of combination reaction involves two elements. When a metal element reacts with a non-mental element, the product is an ________. The formula for this compound product can be predicted from the charges expected for the ______ of the metal and the _____ of the nonmetal.

more

Anions have ______ electrons than protons. To write their electron configurations, we add electrons to the valence level of the atom's electron configuration.

add

Anions have more electrons than protons. To write their electron configurations, we _______ electrons to the valence level of the atom's electron configuration.

−2220 kJ per mol, or q(reaction) = -2220 kJ/mol

Another way to report heat changes in chemical reactions is in units of kilojoules per mole (kJ/mol). Consider the combustion of propane gas, C3H8, used to fuel a gas grill: C3H8(g) + 5O2(g) ----> 3CO2(g) + 4H2O(g) When 1 mol of propane burns, 2220 kJ of heat is released. The heat change for the combustion of propane, then, is _______kJ per mol, or q(reaction) = _________

Cobalt (Co); SnSO4(aq) Co(s) + SnSO4(aq) -----> CoSO4(aq) + Sn(s)

Antonio has two other pieces of metal, cobalt and tin. He also has two aqueous solutions containing their ions, one of cobalt(II) sulfate and one of tin(II) sulfate. Which metal will corrode when placed in one of the solutions? Which solution? Write a balanced equation for the single-displacement reaction where corrosion occurs.

zinc is more active than iron. Therefore, it will displace Fe2+ ions from FeCl2 dissolved in solution. The products of the reaction will be iron metal and zinc chloride. zinc + iron(II) chloride ---> zinc chloride + iron Zn(s) + FeCl2(aq) ----> ZnCl2(aq) + Fe(s)

Antonio has two pieces of metal, zinc and iron. He also has two aqueous solutions, one of zinc chloride and one of iron(II) chloride. Which metal will corrode when placed in one of the solutions? Which solution? Write a balanced equation for the reaction. The word equation is:________________ Substituting the formulas gives us the following skeletal equation:_______________

From its position in the activity series, we know that magnesium reacts with steam to release hydrogen gas: Mg(s) + 2H2O(g) --heat---> Mg(OH)2(aq) + H2(g) If splashed with water from the fountain and heated by the sun, the statue will corrode. Antonio should suggest a different metal.

Antonio is asked to make a magnesium statue to be placed in the middle of a public fountain. Should he take the commission? Why or why not?

combustion reaction

Any reaction that involves oxygen molecules as a reactant and that rapidly produces heat and flame is a ________ reaction.

reactant; product

Any substance that we start with is a _______ and a new substance that forms during the reaction is a ______.

Al3+, Mg2+, Na+, F-, O2-, N3-

Arrange the following isoelectronic ions in order of increasing radius: Al3+, F−, Mg2+, N3−, Na+, O2−.

increases

As atomic numbers increase, the number of electrons ____.

less; absorbed

As shown by the endothermic reaction profile, the energy of the reactants is ______ than the energy of the products. The difference is the energy _______ as the reaction takes place.

f block, and are all metals.

Atoms with electron configurations that match the first pattern [G] ns^2 mf^5 have a partially-filled f subshell, so the corresponding elements lie in the ____ block, and are all _____.

p block; all noble gases, i.e. nonmetals.

Atoms with electron configurations that match the second pattern [G] ns^2 of^14 md^10 np^6 have no partially-filled subshells, but the last filled subshell is a p subshell, so the corresponding elements are in the _____ block. Furthermore, these-block elements with filled p subshells are all ______, i.e. ______.

metals

Atoms with electron configurations that match the third pattern have a partially-filled f subshell, so the corresponding elements lie in the f block, and are all ______.

Zn(s) + 2HNO3(aq) ---> Zn(NO3)2(aq) + H2(g)

Balance the following skeletal equation for the reaction of zinc metal with nitric acid: Zn(s) + HNO3(aq) ---> Zn(NO3)2(aq) +H2(g)

the 2s sublevel and the 2p sublevel.

Because there are two types of orbitals in the second principal energy level, we say that there are two sublevels: the _____ and the _____

q(reaction) + q (water) = 0 q(reaction) = -q(water)

By measuring the temperature change of the water, we can calculate the heat change of the water, qwater, using its specific heat. Assuming no heat is absorbed by the calorimeter, we can determine the heat change for the reaction, q(reaction), using the law of conservation of energy: q(reaction) =______

no, a precipitation reaction only occurs if one of the combination of ions is insoluble

Can a precipitation reaction occur if the possible compounds formed by double displacement are both soluble?

unstable

Carbonic acid, H2CO3, is an _______ substance. It readily decomposes to form water and carbon dioxide

joules (J) or calories (cal with a lowercase c)

Chemists measure energy in units of ______ or _________

oxidation-reduction; 3+; 1−.

Combination reactions in which at least one reactant is an element are also classified as _________ reactions because a change in charge occurs. For example, in the formation of AlBr3 from Al and Br2, the charge on aluminum changes from 0 to ____, and the charge on bromine changes from 0 to____

aqueous sodium chloride and hydrogen sulfide gas 2NaCl(aq) + H2S(g)

Consider a similar reaction. When aqueous sodium sulfide reacts with hydrochloric acid, for example, it forms _______ and _______ Na2S(aq) + 2HCl(aq) ----> _____ + ______

(a). H2 is limiting reactant (b) 1 leftover N2 , 6 NH3 (c). N2 is in excess

Consider the combination reaction of nitrogen gas with hydrogen gas to form ammonia gas: N2(g) + 3H2(g) ---> 2NH3(g) 4 N2 moles 9 H2 moles (a) Identify the limiting reactant, assuming the reaction goes to completion. (b) Draw the "after" picture. Include the correct number of product molecules and any leftover reactant molecules. (c) Determine the reactant that is in excess.

(a). We need 2 N2 molecules to react with the 6 H2 molecules, so we have 4 extra N2 molecules, therefore N2 is in excess. The H2 must be the limiting reactant. (b). Your "after" picture should have 4 NH3 molecules and 4 N2 molecules (c). Because some N2 molecules are left over, there was too much to react, so it is in excess.

Consider the combination reaction of nitrogen gas with hydrogen gas to form ammonia gas: N2(g) + 3H2(g) ---> 2NH3(g) 6 moles N2 and 6 moles of H2 (a) Identify the limiting reactant, assuming the reaction goes to completion. (b) Draw the "after" picture. Include the correct number of product molecules and any leftover reactant molecules. (c) Determine the reactant that is in excess.

N2(g) + 3H2(g) ---> 2NH3(g)

Consider the combination reaction of nitrogen gas with hydrogen gas to form ammonia gas: _______+ _____ ---> _____

2H2 molecules / 1 O2 molecule mole ratio

Consider the combustion of hydrogen to form water. The molecular-level diagram and balanced equation show that the molecule ratio of H2 to O2 is ____/_____The molecule ratio is the same as the ______ ratio because both are related to the coefficients in the balanced equation.

ionic; strong

Consider the reaction of aqueous solutions of lead(II) nitrate and potassium chromate, both of which are _____ compounds and _______ electrolytes. Their reaction is used to prepare the pigment chrome yellow, which is lead(II) chromate, leaving an aqueous solution of potassium nitrate

If the copper had reacted completely, there would be no solid surface for the silver crystals to reside on and they would fall to the bottom of the beaker. Since the silver is still adhering to the copper wire, we know that some copper is still unreacted. Because we can tell that copper metal is in excess, the silver nitrate dissolved in solution must be the limiting reactant. because silver nitrate is the limiting reactant, adding more will allow the reaction to continue, decreasing the amount of copper metal, increasing the amount of silver metal and causing the solution to become a deeper blue. there would be no copper wire present and the silver metal crystals would be lying at the bottom of the beaker

Copper metal is added to an aqueous solution of silver nitrate, producing copper(II) nitrate and silver metal. The solution is blue because copper(II) ions in solution produce a blue color. Note that silver metal crystals have formed at the surface of the copper metal wire. Given that this reaction is complete, identify the limiting reactant and the reactant that is in excess. If you added more silver nitrate to the solution, what would you expect to happen? In Example 6.3 you identified the limiting reactant. Describe what you would observe if the other reactant were the limiting reactant.

silver metal and aqueous copper(II) nitrate Cu(NO3)2(aq) + 2Ag(s) (The blue color of the solution is due to the formation of Cu2+(aq) and a microscopic view shows that the silver metal is deposited as crystals.)

Copper metal reacts with aqueous silver nitrate to form ______ and _______ Cu(s) + 2AgNO3(aq) ---> _______ + _________

acids; nitric acid

Copper, mercury, and gold do not react with _____ to release hydrogen gas, but they do react with ______ to form the metal nitrate and nitrogen dioxide gas.

the metal nitrate and nitrogen dioxide gas Cu(NO3)2(aq) +2NO2(g) + 2H2O(l) oxidation-reduction

Copper, mercury, and gold do not react with acids to release hydrogen gas, but they do react with nitric acid to form ________ and _________. The reaction for copper is given by the following equation: Cu(s) + 4HNO3(aq) ----> _________________ This is another example of an ___________ reaction.

chemical

Corrosion is a process in which a solid metal slowly deteriorates due to a ______ change.

only the nitrate ions (The other species undergo a change: copper element changes to copper ion, and the silver ion changes to silver element) Cu(s) + 2Ag+(aq) ---> Cu2+(aq) + 2Ag(s)

Cu(s) + 2Ag+(aq) + 2NO3-(aq) ---> Cu2+(aq) + 2NO3-(aq) + 2Ag(s) In this reaction, the spectator ions are the _________ ions The net ionic equation omits the spectator ions and shows only those species that change= _______

2NH3(g) + H2SO4(l)

Decomposition Reactions That Occur When Compounds Are Heated: (NH4)2SO4(s) ---heat--->_____ +______

2H2O(l) + O2(g)

Decomposition Reactions That Occur When Compounds Are Heated: 2H2O2(aq) ---heat--> _____ + _____

2Hg(l) + O2(g) Pt(s) + 2Cl2(g)

Decomposition Reactions That Occur When Compounds Are Heated: 2HgO(s) ---heat-->______ + _____ PtCl4(s)---heat--> _____ + ______

lose ammonia

Decomposition Reactions That Occur When Compounds Are Heated: Ammonium compounds _________

CO2(g) +H2O(l) CaO(s) + H2O(g) CuSO4(s) + 5H2O(g)

Decomposition Reactions That Occur When Compounds Are Heated: H2CO3(aq) ---heat---> ____ +______ Ca(OH)2(s) ---heat--> _____+______ CuSO4 · 5H2O(s) ---heat--> _______+________

metal oxides and carbon dioxide gas.

Decomposition Reactions That Occur When Compounds Are Heated: Metal carbonates, except those of the group 1A (1) metals, decompose to ______ and _______

NiO(S) + CO2(g)

Decomposition Reactions That Occur When Compounds Are Heated: NiCO3(s) ---heat--> ______+_______

nonmetal oxides and water

Decomposition Reactions That Occur When Compounds Are Heated: Oxoacids decompose in a similar way to form _____ and _____.

oxides and oxygen gas

Decomposition Reactions That Occur When Compounds Are Heated: Peroxides decompose to _____ and ______.

a). 1.4 x 10^9 g or 1.4 x 10^6 kg. b). 1.6 x 10^9 g or 1.6 x 10^6 kg c). yes, the law of conservation of mass

During an average liftoff, 180,000 kg of hydrogen burned as it reacted with oxygen to form water vapor. The balanced equation for this reaction is 2H2(g) + O2(g) ---> 2H2O(g) (a)What mass of oxygen gas is consumed? (b)What mass of water vapor is produced? (c)Does the mass of water vapor equal the sum of the masses of the reactants? What law is followed here?

energies of electrons were quantized (They could have only certain energies.)

Erwin Schrödinger's model of the atom was similar to Bohr's model in that the _____________. (They could have only certain ________).

To determine the limiting reactant, first determine if there is enough C2H4 to react with 1.0 mol O2: moles of C2H4= 1.0mol O2 x (1 mol C2H4/ 3 mol O2) = 0.33 mol C2H4 We need 0.33 mol C2H4, and we actually have only 0.25 mol C2H4: Because there is not enough C2H4 to react with all the O2, C2H4 is the limiting reactant. Remember that we must use the amount of limiting reactant to calculate the moles of CO2 product: moles of CO2= 0.25 mol C2H4 x (2 mol CO2/ 1 mol C2H4) = 0.50 mol CO2 We also use the amount of the limiting reactant to calculate the amount of O2 that will react: moles O2 that will react= 0.25mol C2H4 x(3 mol O2/1mol C2H4) =0.75mol O2

Ethylene, C2H4, undergoes many useful reactions. However, since it's a hydrocarbon, it is flammable and burns in the presence of oxygen according to the equation C2H4(g) + 3O2 (g) ---> 3CO2 (g) + 2H2O(g) Suppose we mix 0.25 mol C2H4 with 1.0 mol O2. Identify the limiting reactant and the number of moles of CO2 that can be formed.

H2S(g), CO2(g), and SO2(g)

Examples of gases that are commonly produced as part of double-displacement reactions are ____,_____, _____

helium

Except for _________, the Roman numeral group number corresponds to the number of valence electrons because the group number is a sum of the s and p valence electrons.

absorbed or released.

For a chemical reaction, the energy change that is easiest to measure is the heat ________ or _______

decreases.

For any isoelectronic series, as the number of protons increases, the ion size ________

s and p sublevels

For any main-group element, the number of valence electrons is equal to the number of electrons in the highest-energy _____ and ____ sublevels.)

(a) magnesium- 2 (b) carbon- 4 (c) lead - 4

For each of the following elements, determine the number of valence electrons. (a) magnesium (b) carbon (c) lead

(a) 5 (b) 1 (c) 6

For each of the following elements, determine the number of valence electrons. (a) nitrogen (b) potassium (c) oxygen

240 kJ q(reaction) = -q(water) = -240 kJ

For example, if 5.0 g of octane burns in a calorimeter, and the surrounding water absorbs 240 kJ of heat (q(water) = +240 kJ), then the combustion reaction must have released ______ of heat:

H2; H2O; O2, O2

For example, suppose 8 molecules of H2 are mixed with 5 molecules of O2. After the reactants combine in this 2 to 1 ratio, 8 H2O molecules form. The _____ reactant is the limiting reactant because it was completely used up. It limited the number of ______ molecules that could form. The ____ reactant is left over. It was in excess. When the reaction is complete, the 1 leftover ____ molecule that did not react will also be present in the reaction mixture along with the 8 H2O molecules that formed.

two electrons; 2s orbital

For lithium, with three electrons, ________ go in the 1s orbital. The first principal energy level is filled. We can now proceed to the second principal energy level. Because the 2s sublevel is lower in energy than the 2p sublevel, the third electron goes into the ________ orbital

group to which it belongs

For main group elements the number of valence electrons in a neutral atom of the element is determined by the________

seven (The 3d electrons are not valence electrons since they are in the third principal energy level (n = 3). For any main-group element, the number of valence electrons is equal to the number of electrons in the highest-energy s and p sublevels.)

For some elements, some of the core electrons are not part of a noble-gas electron configuration. For example, the abbreviated electron configuration for bromine is Br [Ar]4s^2 3d^10 4p^5 The valence level is the fourth principal energy level (n = 4), which contains ________ valence electrons.

highest-energy sublevel, the p sublevel; np^5

For the halogens, group VIIA (17) , five electrons occupy the _________ sublevel. Each ends in ______.

1s

For the hydrogen atom in its ground state, its electron is in the _____ orbital.

hydrogen

For the__________ atom only, the sublevels within a principal energy level all have the same energy.

heat

From power plant to desk lamp, the overall conversion efficiency is only 1.6%. The other 98.4% of coal's energy is converted to _____ energy before ever performing the desired function: coal--88%--> water/steam--46%--> mechanical energy--98%--> electric energy--4%-->light

zero; q(system) + q(surroundings) = 0

From the law of conservation of energy, the heat change of the system plus the heat change of the surroundings equals ______: ____+____=____

double-displacement

Gas-Formation Reactions In some ________________ reactions, the formation of an insoluble (or only slightly soluble) gas provides the driving force for a reaction.

grams; grams to moles

Generally we measure amounts of reactants in units of ____. based on this, we must first convert from ____ to _____ for each reactant.

If one of the reactants does not react completely, there will be some of it left over at the end of the reaction. The leftover amount will be mixed with the product

How do we know if all of each reactant is used up in the reaction?

983240 J or 9.83 x 10^5 J

How many joules of energy are in a candy bar that contains 235 Cal?

alcohols and sugars

Hydrocarbon compounds that also contain oxygen, such as ______, participate in combustion reactions, producing CO2(g) and H2O(g).

combination reactions can form only one compound (product)

If a certain combustion reaction can also be classified as a combination reaction, how many products can be formed?

yes, as long as the anion contains the SO3 group it is possible to produce SO2(gas)

If a compound contained the HSO3- ion instead of the SO3^2- ion, could a gas-formation reaction still occur?

no, some compounds such as CH4 do not release hydrogen ions and are not acids

If a compound contains hydrogen and another nonmetal, but no other elements, is the compound necessarily an acid?

Yes, the reactivity of aluminum is high enough that it reacts with steam or with acids to give hydrogen gas

If aluminum foil is used to store an acidic food such as lemon slices, is the foil likely to corrode?

the metal piece with the greatest mass would melt the wax the most since it could release the most heat to the wax

If four pieces of the same metal but different masses were heated to the same temperature and then allowed to cool in wax, which metal piece should melt the wax the most? The one with the greatest mass or the least mass, or would all melt the same amount of wax?

above the arrow

If heat must be supplied for the reaction to take place, or if some other special conditions are needed, we describe them ___________ when writing the chemical equation.

carbon monoxide

If insufficient oxygen is present, combustion of a hydrocarbon produces ________ instead of carbon dioxide.

combination

If three elements or compounds react together to form one compound, how would you classify this reaction?

they are reactants

If two elements combine to form a compound, are the elements reactants or products?

stoichiometry

If we know the amount of any reactant or product, we can determine the amount of any other reactant or product in the same reaction by using the balanced equation. The process of determining the amounts of substances in a chemical reaction is called ___________.

multiplying the mass in grams m of a substance by its specific heat C and by the temperature change ΔT (which is the difference between the final temperature and the initial temperature, Tf − Ti): q (heat) = m (mass) x C (specific heat) x ΔT (temperature change)

If we know the specific heat of an object, its mass, and its change in temperature, we can determine the amount of heat absorbed or released. We can calculate the heat (q) associated with a temperature change by__________

1.52 mol H2O x (18.02g H2O / 1 mol H2O) = 27.4g H2O

If we were interested in the mass of the water formed in the reaction, how would we calculate the grams of water from the moles of water just calculated (1.52 mol H2O) ?

least

If you calculate the amount of product predicted from the given amount of each reactant, the calculation that gives the _____ amount of product identifies the limiting reactant.

different energies.

In atoms with more than one electron, the interaction among electrons causes the sublevels within the same principal energy level to have ________ energies

-240kJ / 5.0g = -48kJ/g

In combustion reactions, it's common to report the heat change in terms of the amount of the substance that reacts with oxygen. One common way to report heat changes is in units of kilojoules per gram (kJ/g). We just calculated the heat change for burning 5.0 g of octane. The heat change per gram is one-fifth of the heat change when 5.0 g burns= ______

oxides carbon dioxide and water

In combustion reactions, oxygen combines with other elements in the other reactant to form ______. In this example, the combustion of methane produces ____ and _____

Double-Displacement

In each _________ reaction, two compounds exchange parts to form two new compounds. In all of these reactions, two compounds exchange ions or elements to form new compounds.

stays constant; law of conservation of mass (which states that matter cannot be created or destroyed by ordinary chemical means)

In every chemical reaction the number of atoms of each element ________. This is consistent with the law of conservation of mass

minimize

In order to make the energy possessed by an object most useful to us, we try to _______ the amount of energy lost as heat.

precipitate

In precipitation reactions, reactants exchange ions to form a ______.

metal; nonmetal

In single-displacement reactions, the displaced element is often a ______, but it can be a _____.

water

In some aqueous reactions, there are no spectator ions. An example is the reaction of a highly active metal with ______

2K(s) + 2H2O(l) ----> 2K+(aq) + 2OH-(aq) + H2(g) (shows no spectator ions)

In some aqueous reactions, there are no spectator ions. An example is the reaction of a highly active metal with water: 2K(s) + 2H2O(l) ---> 2KOH(aq) + H2(g) ionic equation= ________

modern

In the ________ model of the atom, principal energy levels describe the allowed energies of the electrons in orbitals.

iron(II) ions Cu(s) + FeO(s) ; copper metal

In the damp environment of New York Harbor, the copper panels on the outside of the statue developed a coating of copper(II) oxide, copper(II) hydroxide, and copper(II) carbonate, while the iron used for the inner framework rusted to form iron(III) oxide. This brought copper metal in contact with iron(III) ions and elemental iron in contact with copper(II) ions. Would either of these combinations undergo a single-displacement reaction? As the National Park Service found out, the answer is yes. The iron was converted to ___________ and the copper(II) ions were converted to ________: Fe(s) + CuO(s) ---> ________+________

2 AgNO3(aq) + MgCl2(aq) ---> 2AgCl(s) + Mg(NO3)2(aq)

In the double-displacement reaction of aqueous silver nitrate and magnesium chloride, silver chloride precipitates and aqueous magnesium nitrate forms: _______---->______

more; released

In the exothermic reaction profile, the reactants contain _____ energy than the products. The difference is the energy ________ during the reaction.

the energies of the principal energy levels.

In the hydrogen atom, the energies of the orbitals are restricted to the_____________

smaller

In the ion, the protons draw the remaining electrons closer to the nucleus. Consequently, the Li+ ion is __________ than the neutral atom.

in the same principal

In the modern model of the atom, orbitals of similar size are considered to be ___________ energy level.

the same

In the modern model of the hydrogen atom, the energy levels have ________ energies as the orbits described in the Bohr model.

aluminum; iron

In the thermite reaction, ______ displaces _____ from its oxide compound.

0 to 3+ 3+ to 0 (aluminum displaces iron)

In the thermite reaction, aluminum changes its charge from ___ to ___, while iron changes its charge from __ to ___

top

In this chemical activity series, the most active elements appear at the _____.

solid, a gas, or an undissociated molecule

In typical double-displacement reactions, one pair of ions combines to form a _____,_____, or ______, leaving the other pair of ions in solution.

Cu(s) + 2AgNO3(aq) --> Cu(NO3)2(aq) + 2Ag(s) ionic: Cu(s) + 2Ag+(aq) + 2NO3-(aq) ---> Cu2+(aq) + 2NO3-(aq) + 2Ag(s) net ionic: Cu(s) + 2Ag+(aq) ---> Cu2+(aq) + 2Ag(s)

Ionic equations can also be written for some single-displacement reactions. An example is the reaction of copper metal with silver nitrate in aqueous solution. write the molecular equation, then the ionic equation, then the net ionic equation.

electrons, protons

Ionic substances consist of charged ions, not neutral atoms. Ions are charged because their number of ________ is greater than or less than their number of _______. To write electron configurations for ions, we adjust the number of valence electrons to account for the charge.

charged ions; neutral atoms

Ionic substances, such as those that create the colors in fireworks, consist of _______ , not _____ .

increases

Ionization energy ________ with each successive removal of an electron.

one line, left to right.

It is common to show a simpler orbital diagram, where all the orbitals are represented on _____ with sublevels labeled. We must remember that the energy of the sublevels increases from _____ to _____

f block; f sublevel

It is enough to note here that the lanthanide and actinide elements are in the ____ block because their highest-energy electron is in an ___________ sublevel.

subscript

It is important to remember that you cannot change the ______ of an element in a compound to balance an equation.

In the first product written, the lead ion and chromate are 2+ and 2−, respectively, so the formula is balanced as is, PbCrO4. In the second product written, the potassium ion and nitrate ion are 1+ and 1−, respectively, so that formula is also already balanced, KNO3. In this case, no subscripts are needed to balance the formulas. most compounds of potassium are soluble and all nitrates are soluble, so KNO3 is water soluble. The only other product is PbCrO4, so it must be the insoluble solid and the identity of the yellow precipitate. We use physical state symbols to show that the precipitate PbCrO4(s) is an insoluble solid and that KNO3(aq) is soluble in water Pb(NO3)2(aq) + K2CrO4(aq) ----> PbCrO4(s) + KNO3(aq) balanced: Pb(NO3)2(aq) + K2CrO4(aq) ----> PbCrO4(s) + 2KNO3(aq)

Janelle finds a recipe for the preparation of the pigment chrome yellow. She dissolves lead(II) nitrate and potassium chromate in separate volumes of water, and then mixes the two solutions. She obtains a yellow precipitate. Identify the precipitate and write a balanced equation for the reaction she carried out.

MgSO3 · 3H2O --heat--> MgSO3(s) + 3H2O(g) **if enough heat is applied, MgSO3(g) can further decompose to magnesium oxide and sulfur dioxide

Janelle wants to make paper pulp to be used in a printing project. She needs magnesium sulfite trihydrate, MgSO3 · 3H2O, to bleach the paper pulp. This compound decomposes upon heating. Predict the products and write complete, balanced equations for any reactions.

2C4H10(g) + 13O2(g)---> 8CO2(g) + 10H2O(g)

Liquid butane is often used as a fuel in cigarette lighters. When the pressure is released, butane evaporates and can burn with oxygen. Balance the following skeletal equation for the reaction of butane with oxygen gas.

MgSO3, Sulfites react with acid to give sulfur dioxide gas. Initially, we have a double-displacement reaction: MgSO3(s) + 2HCl(aq) ---> MgCl2(aq) + H2SO3(aq) the sulfurous acid then undergoes a decomposition reaction: H2SO3(aq) ---> H2O(l) + SO2(g) The overall reaction forms a metal compound with the anion present in the acid, along with liquid water and sulfur dioxide gas: MgSO3(s) + 2HCl(aq) ---> MgCl2(aq) + H2O(l) + SO2(g)

Magnesium sulfite, ______, is used as a bleach to make wood pulp for making paper. A gas is released when this compound is mixed with acid. Identify the gas, and write a balanced chemical equation for the reaction of magnesium sulfite with hydrochloric acid.

heating; calcium carbonate heat---> CaO(s) +CO2(g)

Many metal compounds containing oxoanions, such as carbonates, decompose upon _________. A common example is __________ CaCO3(s) --_____--> _____+_____

hydrogen sulfide ZnCl2(aq) +H2S(g)

Many sulfide compounds, such as the ZnS used in some television screens, will react with acids to form gaseous _____________ ZnS(s) + 2HCl(aq) ---> ________+ _______

2MgO(s)

Metal combustion: 2Mg(s) + O2(g) ----> ____

spectator

Metal ions of group IA (1) always form soluble compounds, so they are always ______ ions in double-displacement reactions

bases

Metal oxides can behave like ________ when dissolved in water because they react with water to form metal hydroxides.

metal hydroxides

Metal oxides can behave like bases when dissolved in water because they react with water to form ___________

single-displacement

Metals that are even less reactive, such as copper, do not react with either water or acids in a ________ reaction.

water

Metals that are still less reactive do not react with _____ at all, but they do displace hydrogen from acids.

hydrogen CoCl2(aq) + H2(g)

Metals that are still less reactive do not react with water at all, but they do displace ______ from acids. Cobalt is an example: Co(s) + 2HCI(aq) ---->_____________

Michelle could use CoCO3 or Co(OH)2. Metal carbonates lose carbon dioxide gas when heated, leaving a metal oxide: CoCO3(s) --heat---> CoO(s) +CO2(g) Metal hydroxides lose water to form metal oxides: Co(OH)2(s) --heat--> CoO(s) +H2O(g) Heating a hydrate results in the loss of gaseous water: CoCl2 · 6H2O(s) ---heat--> CoCl2(s) +6H2O(g) We have seen no patterns that suggest that anything would happen to CoS upon heating.

Michelle, another art student, needs some cobalt(II) oxide to make cobalt glass. She has the following cobalt compounds available to her: CoCl2 · 6H2O, CoCO3, CoS, and Co(OH)2 Which of these compounds can make the cobalt(II) oxide she needs? What products would form if the other compounds were heated?

the yellow solid lead(II) chromate; a solution of potassium nitrate.

Mixing solutions of lead nitrate and potassium chromate produces _________ and _____________

soluble; insoluble Pb2+(aq)+ 2NO3-(aq) +2K+(aq)+ CrO4^2-(aq)-->PbCrO4(s)+ 2K+(aq)+2NO3-(aq)

Mixing solutions of lead nitrate and potassium chromate produces the yellow solid lead(II) chromate and a solution of potassium nitrate. in the molecular equation, the _______ ionic compounds exist as separated ions in aqueous solution. The ________ PbCrO4(s) product does not exist as separate ions. The following ionic equation represents the soluble ionic substances more appropriately: _____+______=______+_______

Pb(NO3)2(aq) + K2CrO4(aq) ---> PbCrO4(s) + 2KNO3(aq)

Mixing solutions of lead nitrate and potassium chromate produces the yellow solid lead(II) chromate and a solution of potassium nitrate. write the equation for this reaction:

coefficients

Mole ratios are obtained from the ________ in a balanced equation.

stable water molecules from hydrogen ions and hydroxide ions

Normally, an acid reacts with a base to form an ionic compound and water. The formation of ________ molecules from ______ ions and _________ ions is the driving force for neutralization reactions.

increases; relatively constant; lower

Note that the energy released per mole generally _________ with the number of carbon atoms in the molecular formula. However, the energy released per gram is __________ for compounds that contain only carbon and hydrogen. The energy released per gram is _______ for methanol and ethanol, which also contain oxygen.

core

Note that the valence electrons in silicon are the electrons that are written after the electron configuration for neon. Electrons that make up a noble-gas electron configuration are _______ electrons held very strongly by the nucleus.

Ca [Ar]4s^2

Notice that argon and calcium differ only by the 4s2 electrons at the end of the electron configuration for Ca: Ar 1s^2 2s^2 2p^6 3s^2 3p^6 Ca 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 Instead of writing the complete electron configuration for Ca, we will use the symbol [Ar] to represent the part of calcium's electron configuration that corresponds to argon. The abbreviated electron configuration for Ca substitutes [Ar] for the first part of its electron configuration: _________

Si 1s^2 2s^2 2p^6 3s^2 3p^2 or [Ne]3s^2 3p^2 four valence electrons. (The valence level is the n = 3 principal energy level, which contains the 3s and 3p sublevels. From the electron configuration, we can see that there are a total of four electrons in the n = 3 principal energy level. Thus, silicon has four valence electrons)

One way to determine the number of valence electrons for an element is to look at its electron configuration or its abbreviated electron configuration. For example, the electron configuration for silicon is _____________________ . Thus, silicon has ________ valence electrons.

lowest-energy

Orbitals come in different shapes and sizes. There are four types of occupied orbitals in atoms in their ________ states, which we label with the letters s, p, d, and f. These orbitals are distributed into the principal energy levels.

copper; silver an ionic copper(II) compound in solution:

Other elements can also be displaced from their compounds. For example, if a piece of copper metal is placed in an aqueous solution of silver nitrate, ____ displaces _____ and silver metal is deposited on the surface of the copper. The copper is converted to ________:

insoluble (CrO4^2-) Na+, K+, NH4+ , Mg2+, Ca2+, Al3+, and Ni2+.

Rules Used to Predict the Solubility of Ionic Compounds Most chromates are ______ (ex.______). Exceptions are compounds of ____,____,___,____,___,___,____

soluble (SO4^2-) BaSO4, SrSO4, PbSO4, CaSO4, Hg2SO4, and Ag2SO4.

Rules Used to Predict the Solubility of Ionic Compounds Most sulfates are _______(ex ______) . Exceptions are ______,____,____,____,____, and ____.

insoluble AgNO3 and AgClO4 AgCH3CO2

Rules Used to Predict the Solubility of Ionic Compounds Silver compounds are ______(ex.____) except ___ and ____ ______ is slightly soluble.

insoluble (S2−) Na+, K+, NH4+, and the alkaline earth metal ions.

Rules Used to Predict the Solubility of Ionic Compounds Sulfides are _______. (ex._____) Exceptions are compounds of ___,____,___,____

soluble Na+, K+, NH4+ , alkali metal ions

Rules Used to Predict the Solubility of Ionic Compounds most compounds of alkali metals and ammonium ions are ______ Ions: ___,____,___ (and all other _____)

insoluble; (O2−, OH−) alkali metal hydroxides, Ba(OH)2, Sr(OH)2 Ca(OH)2

Rules Used to Predict the Solubility of Ionic Compounds: Oxides and hydroxides are _______. (ex. ____,____) Exceptions are __________, _____,______ _______(somewhat soluble).

Ionic

Rules Used to Predict the Solubility of _____ Compounds: 1. Most compounds of alkali metal and ammonium ions are soluble. 2. All nitrates and acetates are soluble. 3. Most sulfates are soluble. Exceptions are BaSO4, SrSO4, PbSO4, CaSO4, Hg2SO4, and Ag2SO4. 4. Most chlorides, bromides, and iodides are soluble. Exceptions are AgX, Hg2X2, PbX2, and HgI2. (X = Cl, Br, or I.) 5. Silver compounds, except AgNO3 and AgClO4, are insoluble. AgCH3CO2 is slightly soluble. 6. Oxides and hydroxides are insoluble. Exceptions are alkali metal hydroxides, Ba(OH)2, Sr(OH)2, and Ca(OH)2 (somewhat soluble). 7. Sulfides are insoluble. Exceptions are compounds of Na+, K+, NH4+, and the alkaline earth metal ions. 8. Most chromates are insoluble. Exceptions are compounds of Na+, K+, NH4+ , Mg2+, Ca2+, Al3+, and Ni2+. 9. Most carbonates, phosphates, sulfites, and silicates are insoluble. Exceptions are compounds of Na+, K+, and NH4+

+1; one less, 2

Since the Ga+ ion has a charge of ____ it has ______ electron than a neutral atom of Ga so it has ____ valence electrons

10; 6; 8

Since the coefficients in this equation represent the relative numbers of reactant and product molecules, the equation reveals the amounts of reactants and products at any scale. The relative numbers of reactants and products remain the same (1 C3H8 : 5 O2 : 3 CO2 : 4 H2O). For example, if 2 molecules of C3H8 react, they must combine with _____ molecules of O2, producing ___ molecules of CO2 and ___ molecules of H2O.

Na2CO3 is the limiting reactant 4.57 g CO2 produced

Sodium carbonate reacts with hydrochloric acid to produce aqueous sodium chloride, water, and carbon dioxide gas. The balanced equation is: Na2CO3(s) + 2HCl(aq) -----> 2NaCl(aq) + H2O(l) + CO2(g) Determine the limiting reactant and mass of CO2 gas produced when 11.0 g of Na2CO3 is added to a solution that contains 11.0 g of HCl.

Na2CO3(s) + 2HCl(aq) -----> 2NaCl(aq) + H2O(l) + CO2(g)

Sodium carbonate reacts with hydrochloric acid to produce aqueous sodium chloride, water, and carbon dioxide gas. The balanced equation is: _______-->______

The actual yield is the number of moles of H2 that was isolated once the reaction occurred (0.21 mol). The theoretical yield must be calculated from the amount of limiting reactant that reacted. In this case we can assume the Na is the limiting reactant (not the water) because all the Na reacted. We calculate the theoretical yield by calculating the maximum number of moles of H2 that should be produced from the moles of limiting reactant Na: moles H2= 0.50 mol Na x (1 mol H2/2 mol Na) = 0.25 mol H2 (theoretical yield) percent yield= (actual yield/ theoretical yield) x 100% percent yield= (0.21 mol H2/ 0.25 mol H2) x 100% = 84%

Sodium metal reacts with water in a single-displacement reaction to produce aqueous sodium hydroxide and hydrogen gas. The balanced equation is: 2Na(s) + 2H2O(l) ---> 2NaOH (aq)+ H2(g) When 0.50 mol Na is placed in water, all the sodium metal reacts, and the hydrogen gas produced is isolated. It is determined that 0.21 mol H2 has been produced. What is the percent yield of H2?

1a). reactants; products 1b). physical state symbols 1c). 1 2a). coefficient 2b). subscripts 2c). coefficients 2d). elemental substances 3. balanced

Steps for Balancing Equations 1. What is the skeletal equation? (a) Write correct formulas for _____ on the left side and ______ on the right side of the arrow. (b) Include _________ for all substances. (c)The coefficients (the numbers preceding the formulas) are all _____ in a skeletal equation. 2. How are atoms of each element balanced? (a)First look for elements that appear only once on each side of the equation. If there are different numbers of atoms of that element on each side of the equation, change the ______ of one or both substances until there is the same number of atoms on each side of the equation. (b)Do not change the ______! Changing them in a formula would change the identity of the substance. (c)Continue checking all elements in the equation, changing ____ when needed. (d)The last atoms to balance should be those in _______ substances (such as O2), because changing a coefficient in front does not change the numbers of atoms of any other elements. 3. Is the equation ______? Make a final check by counting the atoms of each element on both sides of the equation. If they are the same, then the equation is.

a single 3s orbitals; a set of three 3p orbitals; five d orbitals

The 3s sublevel consists of ________ orbital, and the 3p sublevel consists of _________ orbitals. The 3d sublevel consists of _____ orbitals.

seven 4f orbitals.

The 4f sublevel consists of ________ orbitals.

greater

The actual yield can appear _______ if a solid is weighed when still wet or if a product is contaminated.

less

The actual yield is usually _______ than the theoretical yield

the corresponding alkali metal hydroxide and hydrogen gas

The alkali metals all react with water to form ______ and _____

soft, reactive ; ionic compounds or dissolved ions; closed containers.

The alkali metals are all _____,______ metals. so much so that they are not found in nature as metals, but only as _______ compounds or ______ ions. Since the metals react with oxygen in air and with water, they must be stored in _________

less

The amount of energy released depends on the amount of substance burned. A few drops of a substance will produce much _______ heat than a gallon of that substance.

the mass, the specific heat, and the change, or difference, in temperature.

The amount of heat absorbed by a substance when it increases in temperature equals the amount of heat released when it cools back down to the same temperature. The amount of heat transferred to or from a substance is related to the ____, the _____, the _______

negative

The combustion reaction is releasing heat, so its value of q is _______.

transition

The d-sublevel electrons are sometimes counted as valence electrons for __________ metals, but the behavior of these electrons is less predictable than the valence electrons for main-group elements.

0.20 g of water vapor is produced.

The decomposition of nitroglycerin is an explosive reaction that produces four different gases. What mass of water vapor should be produced when 1.0 g of nitroglycerin decomposes by the following reaction? 4C3H5O9N3(l) -----> 12CO2(g) + 6N2(g) +O2(g) + 10H2O(g)

single-displacement

The displacement of hydrogen from water or acids is just one type of _________ reaction. Other elements can also be displaced from their compounds.

isoelectronic

The electron configurations for Ca2+ and Cl− are identical, and they are the same as for an argon atom. The Ca2+ cation, the Cl− anion, and the Ar atom are ______________ because they have the same number of electrons. Even so, the three are different because they have different numbers of protons.

Li = 1s^2 2s^1 Na= 1s^2 2s^2 2p^6 3s^1 K= 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 Rb= 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^1

The electron configurations for Li, Na, K, and Rb are: Li = ________ Na= ________ K= _________ Rb= __________

no charge; equals

The electron configurations we have written so far are for atoms. Because atoms have _______ charge, the number of electrons _______ the number of protons (which is the atomic number)

proteins, fats, and carbohydrates.

The energy content of foods comes primarily from _____,____, and _____.

(a) The value of q is negative, so the reaction is exothermic; energy is released by the reaction. (b) To calculate the heat change when 0.200 mol CH3CH2OH reacts, multiply 0.200 mol CH3CH2OH by the heat change per mole of CH3CH2OH: 0.200mol x (-1367kJ/1 mol)=-273kJ When 0.200 mol CH3CH2OH reacts, 273 kJ of heat is released to the surroundings.

The ethanol, CH3CH2OH, in Lily's car burns with excess oxygen according to the following equation: CH3CH2OH(l) + 3O2(g) --> 2CO2(g) + 3H2O(l) The heat change q for this reaction is −1367 kJ per mole of CH3CH2OH that reacts. (a) Is this reaction endothermic or exothermic? (b) What is the heat change when 0.200 mol of ethanol burns?

s; 1s orbital; it is in the n = 1 principal energy level and it has the s orbital shape

The first principal energy level (n = 1) consists of a single ____ orbital. We call this orbital a ________ because it is in the _________ energy level and has the ________ shape

combustion and combination

The following are examples of both ____ and ____ reactions: 2Mg(s) + O2(g) ----> 2MgO(s) S(s) + O2(g) --> SO2(g)

(a) The reaction releases the energy that is converted to useful energy (electricity) by the fuel cell. Since energy is released by the reaction, it is exothermic. (b) The reverse of this reaction requires a continuous energy input (electricity) to convert from reactants to products, so it is an endothermic reaction. If a reaction is exothermic, its reverse reaction is endothermic.

The following is the reaction used in a hydrogen fuel cell to produce electricity: 2H2(g) + O2(g) --> 2H2O(g) (a) Is this reaction endothermic or exothermic? (b) The reverse of this reaction, the formation of hydrogen and oxygen from water, can be accomplished by running electricity through water. Is this reaction endothermic or exothermic? Explain.

the reactant mixture of H2 and O2 is higher in potential energy than the product because the reaction is exothermic

The following is the reaction used in a hydrogen fuel cell to produce electricity: 2H2(g) + O2(g) --> 2H2O(g) Which is higher in potential energy: A mixture of H2 and O2 gases or pure H2O gas?

neutralization

The formation of stable water molecules from hydrogen ions and hydroxide ions is the driving force for _______ reactions

the 4s, 4p, 4d, and 4f

The fourth principal energy level (n = 4) consists of four sublevels: _________ sublevels.

bottom to top and from left to right

The general tendency is for ionization energy to increase from _____ to _____ and from ____ to _______ across the periodic table

ns^2

The group IIA (2) elements have a similar pattern. Each ends in _________

p block; highest-energy electron is in a p sublevel

The halogens and noble gases, along with the other elements in groups IIIA (13) through VIIIA (18), are in the ____ block of the periodic table because their _________.

higher; lower; the same energy

The hydrogen line spectrum is produced by the movement of electrons in an atom from orbitals in _____ principal energy levels to orbitals in ______ principal energy levels. The hydrogen atom line spectrum is simple to explain because the orbitals in the same principal energy level have ________. This is not the case for atoms with more than one electron.

nonmetals

The lack of d electrons outside the noble-gas core tells you these elements must be in Periods 2 and 3, and the elements in Periods 2 and 3 with three or four p electrons (N, O, P, and S) are all _________.

irregularities

The lanthanides and actinides are rarely encountered, and many ___________ occur in their electron configurations.

valence level, or valence shell

The last-occupied principal energy level is called the _______ or ______.

converted or transferred, created or destroyed.

The law of conservation of energy expresses this principle: Energy can be ___________, but it cannot be____________

the probability of finding an electron in a region outside the nucleus

The mathematical model was based on _____________. (From it chemists created a probability map )

hydroxide

The most common bases are ______ compounds of metals.

hydrocarbons

The most common combustion reactions involve ________ as one of the reactants.

inert; react chemically with other elements.

The neon in the signs that Andrea, Ben, and Drew saw in Las Vegas emits light when charged with electricity, but it is ______. That is, it does not ________

Roman numeral group number; Helium

The number of valence electrons can be determined from the ____________ for main group elements, except for _______ element.

3A; Periods 4 or 5, and all Group 3A elements in these periods are metals; metals

The p-block elements with one p electron are all in Group _______ In this case, the full d subshell and the lack of f electrons is actually enough to tell you these elements lie in Periods____ or _____ and all these Group elements in these periods are ______.

actual yield, theoretical yield

The percent yield describes how much of a product is actually formed in comparison to how much should have been formed. It is the ______ yield expressed as a percentage of the ______ yield:

blocks

The periodic table can be subdivided into different _______; each one correspond to the highest-energy electrons—those that are in the last-occupied sublevel when we write electron configurations.

s and p blocks; d block; f block

The periodic table helps us determine the electron configuration for an element. The principal energy level number n written before the sublevel letter is obtained from the period number. For the ____ and ____ blocks, n is the period number (row number). For the ______ block, n is one less than the period number. For the ______ block, n is two less than the period number.

the same number of valence electrons

The periodic table shows that elements in the same group have the same number of ___________

periodicity

The principle of _____ suggests that the other alkali metals, like lithium metal, will also react with water to form a metal hydroxide and hydrogen gas.

calorimeter calorimetry

The process commonly used to determine the heat change for an object for which we do not know the specific heat, or if the initial temperature of the object is difficult to measure. The insulated container is commonly called a ______. The measurement of heat transfer using a calorimeter is called ______.

smallest possible whole numbers

The process of balancing an equation involves examining and modifying coefficients until the reactants and products contain the same numbers of the component elements. The coefficients are written as the ____________.

BaS(aq) + H2SO4(aq) ---> BaSO4(aq) + H2S(g)

The reaction of barium sulfide with sulfuric acid is used to prepare barium sulfate. Barium sulfate, combined with zinc sulfide and zinc oxide, is used to make the white pigment lithopone. Write a balanced equation for the reaction of barium sulfide with sulfuric acid.

corrosion

The reaction of metals with acids is sometimes called _______, especially if the result is undesirable.

ammonia ( Ammonia is used to produce fertilizer for plants that help feed much of the world population.)

The reaction of nitrogen gas with hydrogen gas to produce ______ is very important.

sodium chloride; Na and Cl2; NaCl 2Na(s) +Cl2(g) ---> 2NaCl(s)

The reaction of the elements sodium metal and chlorine gas to form the ionic compound ________ is another example where the formula of the product can be produced from the charges expected for the ions (Na+ and Cl−). Once we write the correct formulas for the reactants (Na and Cl2) and product (____), we can then balance the equation with coefficients: ____+____---> ____

gaseous oxygen molecules; liquid state

The regular array of mercury(II) ions and oxide ions breaks down when mercury(II) oxide is heated. The oxide ions form oxygen atoms, which combine to form ________ The mercury(II) ions form mercury metal in the ________ state

increases

The size of the orbital ________ as the principal energy level increases.

-6910 J; negative; the reaction is exothermic

The specific heat of aluminum is 0.895 J/(g °C). If 156 g of aluminum at 75.0°C is cooled to 25.5°C, how much heat is transferred? What is the sign of q, and what is its significance?

overlapping at the nucleus and perpendicular

The three 2p orbitals lie with their centers __________ and _______ to one another. We can think of each two-lobed orbital as directed along one of the x, y, or z axes. We label these orbitals accordingly as px, py, and pz orbitals.

hard, with high melting points and boiling points

The transition metals are ____, with ____ melting points and boiling points. They are used extensively to manufacture metallic objects where hardness, strength, low reactivity, or electrical conductivity is an important property.

seven 4f

There are 14 lanthanides, this number corresponding to the number of electrons that can fill the _______ orbitals.

stability

There are a few minor exceptions to the normal filling order for electron configurations: Notably, the lanthanides and actinides vary from a predictable pattern. Also some of the transition metal elements in group VIB (6) and group IB (11) have electron configurations different from what the filling rules predict. The deviations result from the extra ________ of half-filled and completely filled d sublevels.

heat change = 2.00mol C3H8 x (-2220kJ/ 1 mol C3H8) = -4440kJ

This ratio is described as the heat of reaction, and it allows us to calculate the heat change when any molar amount of propane reacts. For example, if 2.00 mol of propane reacts, twice as much heat is released. This can be calculated by multiplying the 2.00 mol propane by the heat change per mole: heat change = _____

atoms; molecules

To balance an equation, we need equal numbers of _____ of each element on each side of the equation but not necessarily equal numbers of ______.

insoluble

To identify the precipitate, we determine which product of double displacement is insoluble in water.

noble gas in the period above the element

To write an abbreviated electron configuration for an element, locate its position on the periodic table and find the closest __________ in the period ______. Use this noble gas in the abbreviation. Once you have written the noble-gas symbol in brackets, add the additional electron configuration needed to reach the element on the periodic table.

because zinc reacts with the acid in tomatoes

Tomatoes are acidic. Why don't we use iron cans coated with zinc to hold tomato sauce?

68%

Toxic carbon monoxide is a by-product of the preparation of hydrogen fuel from methanol for use in hydrogen-powered vehicles. When carbon monoxide reacts with oxygen gas, the greenhouse gas carbon dioxide is produced: 2CO(g) + O2(g) ---> 2CO2(g) When 5.0 mol CO is mixed with excess O2, the reaction occurs to give 3.4 mol CO2. What is the percent yield of CO2?

white solid calcium carbonate; CaCO3(s) hardening and aging

Two compounds may react to form a new compound. For example, calcium oxide, a white solid, reacts with carbon dioxide to form _________, which is found naturally in limestone, marble, and seashells: CaO(s) + CO2(g) ----> _____ reactions such as this happen during the____and _____of cement

Mg(OH)2(aq) + HCl(aq) ---> MgCl2(aq) + H2O(l) complete balanced equation: Mg(OH)2(s) + 2HCl(aq) ----> MgCl2(aq) + 2H2O(l)

Upset stomachs are sometimes treated with an antacid that is a suspension of magnesium hydroxide in water. Stomach acid is hydrochloric acid. Write a skeleton equation and a balanced equation for the reaction that occurs when magnesium hydroxide mixes with stomach acid.

2p^2

We do not have to show the number of electrons in each p orbital. for instance, in the arrangement of electrons in a carbon atom the last sublevel that contains electrons is the 2p sublevel, so we write the electron configuration to show the total number of electrons in the 2p sublevel____

Change in color Production of light Formation of a solid (such as a precipitate in solution, smoke in air, or a metal coating) Formation of a gas (bubbles in solution or fumes in the gaseous state) Absorption or release of heat (sometimes appearing as a flame)

What are some visible clues that would indicate that a chemical reaction MAY have occurred?

differ in the number of protons in the nucleus and they have different ion charges

What are some ways that isoelectronic ions differ?

They are those species that undergo no change and therefore are shown on both sides of the ionic equation.

What are the spectator ions?

Br [Ar]4s^2 3d^10 4p^5 (The closest noble gas above bromine is argon. Argon is at the end of period 3, so we add the electrons that correspond to the blocks we must pass through in period 4 to get to bromine, just as we do when we write the complete electron configuration.)

What is the abbreviated electron configuration for bromine, Br?

the first is called a precipitation reaction, one product compound separates from the reaction mixture because it is insoluble. It forms a solid. the second is when one product compound separates from the reaction mixture as an insoluble gas. In the third example, a stable molecular substance, water, is formed.

What is the driving force that causes two compounds to exchange partners in a double displacement reaction?

metal oxides and carbon dioxide

What product is always formed when a metal carbonate compound undergoes a decomposition reaction?

Na

When 0.50 mol Na is mixed with 0.20 mol Cl2, 0.40 mol Na reacts with 0.20 mol Cl2. When the reaction is complete, 0.40 mol NaCl is produced. Because the _____ is in excess by 0.10 mol, that amount, along with the 0.40 mol NaCl that forms, will be present when the reaction is complete.

H2; O2

When 8 H2 molecules and 5 O2 molecules are combined, all of the H2 reacts and 1 O2 molecule is left over. The limiting reactant is ______, and ______ is in excess.

endothermic; when the battery runs energy is released. recharging a battery is the opposite reaction, so recharging must be endothermic

When a car battery does not work, it can usually be recharged so that it is useful again. Recharging a battery involves running the reaction in reverse. Is this reaction an endothermic or exothermic process? Explain.

thermite reaction

When a powdered mixture of aluminum metal and iron(III) oxide is heated, it reacts vigorously to form liquid iron metal and aluminum oxide. This reaction is called the_________

no

When all ions are spectator ions, ________ reaction occurs.

carbon dioxide gas

When an acid reacts with a metal carbonate, bubbles of _______ form.

water and aqueous potassium nitrate H2O(l) + KNO3(aq)

When aqueous potassium hydroxide reacts with aqueous nitric acid, it forms ____ and _____ KOH(aq) + HNO3(aq) ---->_______ + ________

molecular compound colorless gaseous sulfur dioxide 8SO2(g)

When both reactants of a combination reaction are nonmetal elements, they would combine to produce a ________ For example, the yellow solid sulfur reacts with oxygen gas to form ________ S8(s) + 8O2(g) ---> _______

2 Al(s) + 3Br2(l) ---> 2AlBr3(s)

When liquid bromine is mixed with aluminum metal, a combination reaction occurs, forming aluminum bromide: ______ ---> ______

2Mg(s) + O2(g) --> 2MgO(s) 3Mg(s) + N2(g) --> Mg3N2(s)

When magnesium metal burns in air, it forms two white compounds. One is the compound expected for the reaction of magnesium with oxygen in air, while the other, magnesium nitride, Mg3N2, results from a reaction with nitrogen in air. Predict the product of the reaction of magnesium with oxygen. Write complete, balanced equations for the reactions that form both products.

water vapor, carbon dioxide

When plenty of oxygen is available for the reaction, the hydrogen in hydrocarbons forms ______, and the carbon forms _________

2Ca(s) + O2(g) ---> 2CaO(s)

When pure calcium metal is exposed to the oxygen in air, a white coating appears on the surface. Predict the product and write a complete, balanced equation for this reaction.

2Na(s) + 2H2O(l) ---> 2NaOH(aq) +H2(g)

When sodium metal is dropped into liquid water, the mixture releases gaseous hydrogen, leaving behind a colorless solution of sodium hydroxide. Balance the equation that represents this reaction.

lose their negative charge; oxygen atoms; lose their positive charge; mercury atoms

When solid mercury(II) oxide (HgO) is heated, the oxide ions _______________ as they are converted to _______ The mercury(II) ions _______ to form ______

barium sulfate ; sodium chloride

When solutions of barium chloride and sodium sulfate mix, a precipitate of ________ forms, leaving _______ in the solution. BaCl2(aq) + Na2SO4(aq) ----> BaSO4(s) + NaCl(aq)

skeletal equation or an unbalanced equation

When the atoms of the reactants and products have not yet been equalized, the equation is called a ______ or __________

negative (q < 0) positive value (q > 0)

When the system releases heat to the surroundings, q is a _______ value. When the system absorbs heat from the surroundings, q is a _____ value

positive, absorbed, hotter negative, released, cools down

When the temperature of a substance increases (ΔT is positive), q has a _____ value; heat is _____ by the substance and it gets _____. When the temperature decreases (ΔT is negative), q is _____; heat is _____ by the substance and it ______.

add one electron at a time

When we create an orbital diagram for a particular atom, we fill in electrons starting with a bare nucleus and _____________. (This is not how atoms are created in nature.)

coefficients

When writing chemical equation we indicate the relative number of molecules or formula units of reactants or products by ________, which are whole numbers that immediately precede the formula of each substance.

number of the principal energy level; symbol for the sublevel; superscript to each sublevel symbol to indicate the number of electrons in that sublevel.

When writing electron configurations, we write the____________ followed by the ______________. We then add a __________.

It comes from chemical energy that is stored as potential energy in the fuel. It is stored in the bonds that hold atoms together in molecules.

Where does the energy come from? Where is it stored?

excess; completely

Why don't we use the exact amounts of each reactant that are needed for the reaction? Small errors can always lead to a slight excess of one reactant that might contaminate the product. To ensure that a selected reactant is used completely, we commonly use an excess of the other reactant. For example, silver bromide used in photographic films is prepared by the reaction of potassium bromide and silver nitrate solutions. Potassium bromide is used in _______ to ensure that all of the more expensive silver nitrate is used _______.

No

Will a single-displacement reaction occur with all combinations of metals and ionic compounds?

(a) S2− = [Ne]3s^2 3p^6 or [Ar] The electron configuration for S2− is the same as that of the noble gas argon, so ions that are isoelectronic with Ar are also isoelectronic with S2−. Examples include P3−, Cl−, K+, and Ca2+. (b) Sr2+ = [Kr] ons that are isoelectronic with Kr are also isoelectronic with Sr2+. Examples are Se2−, Br−, and Rb+. Some transition metals are also isoelectronic with Sr2+. An example is Zr4+. (c) Al3+ = [Ne] The Al3+ ion has 10 electrons like neon. Other ions with 10 electrons include O2−, F−, Na+, and Mg2+.

Write the abbreviated electron configuration for each of the following ions. For each ion identify another ion that is isoelectronic with it. (a) S2− (b) Sr2+ (c) Al3+

two; two; opposite

You may have also noted that no more than ____ electrons occupy each orbital. This is the basis for the Pauli exclusion principle, which states that a maximum of ____ electrons can occupy each orbital, and they must have _____ spins.

two; only one or none

You may have noticed that the lowest-energy orbitals have ____ electrons in them, and some of the higher-energy orbitals have ______ or ________.

aufbau principle (from the German aufbauen, "to build up")

You may have noticed that the lowest-energy orbitals have two electrons in them, and some of the higher-energy orbitals have only one or none. This is a result of the ______ principle.

right

You might think that size should increase because the number of electrons increases, but the electrons are added to the same principal energy level while the positive charge in the nucleus increases. As we move from left to right across a period, the increased positive charge in the nucleus becomes more effective at drawing the valence electrons closer to the center of the atom, causing atoms to the __________ on the periodic table to be smaller in size.

combination

_____ chemical reaction A + B ---> AB (2 elements of compounds produce 1 compound)

single-displacement

_____ chemical reaction A + CD ----> C + AD (1 element and 1 compound produce 1 element and 1 compound)

double-displacement

_____ chemical reaction CD + EF ----> CF + ED (2 compounds produce 2 compounds)

decomposition

_____ chemical reaction CD ---> C+D (1 compound produces 2 elements or smaller compounds)

Electrons

_____ in the same orbital are represented by arrows that point in opposite directions. they can spin in one of two directions. We represent these spins with an up arrow (↑) and a down arrow (↓).

precipitation reaction

_____ is a reaction in which the reactants in solution exchange ions to form a solid

ionic equation

_____= a form of a chemical equation in which ion species are represented as the separated ions

the aufbau principle

______ = an approach to writing ground-state electron configurations of atoms by filling orbitals that are lowest in energy first; means "building up" in German

bases

______ are compounds that neutralize acids; they react with the hydrogen ions released by acids.

Corrosion

______ is a process in which a solid metal slowly deteriorates due to a chemical change.

Hydrogen

______ provides the most energy per gram, which is one reason why it offers promise as a fuel of the future.

chemical

______ reactions neither destroy atoms nor create new atoms. They occur because the bonds that hold atoms together can be broken and rearranged.

Cerium (58)

______ the first element of the lanthanide series, is the first element in the f-block series

spectator ions

______= an ion that appears on both sides of an ionic equation and is therefore not involved in a chemical change (the ion does not undergo a change)

Hydrocarbons

_______ are chemical compounds made only of hydrogen and carbon.

Nothing

_______ happens when we place a piece of silver in a solution of copper(II) nitrate

Helium

_______ has its electrons in the 1s sublevel. It cannot have an electron in a p sublevel, like the rest of the noble gases, because it has only two electrons and there is no 1p orbital.

Erwin Schrödinger

_______, developed a mathematical model that seemed to work for all atoms.

net ionic equation

_______= a form of a chemical equation in which ionic compounds are represented as the separated ions and spectator ions are eliminated

core electron

_______= an electron in an atom that is not a valence electron; an inner electron.

Mole ratio

________ help us determine the moles of one substance in a reaction when the number of moles of another substance in a reaction is known moles known substance ---______--> moles unknown substance

Decomposition; combination

________ reactions may form more than two products in some cases. Similarly, _______ reactions may involve more than two reactants.

reaction profiles

________, which describe the overall energy changes that accompany exothermic and endothermic reactions.

stoichiometry

________= the use of quantitative relationships between substances involved in a chemical reaction to determine the amount of a reactant or product.

A chemical equation

_________ is a symbolic representation of a chemical reaction (consisting of chemical symbols and formulas)

heat

_________ is energy that is transferred between two objects because of a difference in their temperatures.

Valence Level (shell)

_________= the principal energy level that is highest in energy and contains the largest occupied orbitals.

molecular equation

__________ = a form of chemical equation in which substances are represented as if they existed as molecules (using formula units) even though the substances may exist in solution as ions.

neutralization reaction

__________ = a reaction of an acid and a base to form an ionic compound and water

Efficiency

__________ is a measure of the amount of useful work that is achieved from an energy conversion.

electron configuration

__________, which shows the distribution of electrons among sublevels, are a shorter way to convey the same information as orbital diagrams.

valence electron

___________ = an electron that occupies/ is in the highest principal energy level, the valence level.

limiting reactant (reagent)

___________ = the reactant that is completely used up in the reaction and therefore determines the amount of other reactants that react and the amount of products that should form.

limiting reactant (reagent)

___________ limits the amount of the other reactant that can react, and it limits the amount of product that can form.

precipitation reaction

____________ reaction =one product compound separates from the reaction mixture because it is insoluble and then forms a solid

net ionic equation

a _______ equation only includes those substances that are involved in the reaction

nonmetal

an atom with either of these electron configuration patterns corresponds to a _______: [G] ns^2 np^3 [G] ns^2 np^4

increases

as we go from top to bottom in a group, the atomic radius ________ because the valence electrons are in larger orbitals.

increases

atomic size ________ as you move from right to left on periodic table

positive silver atoms

atoms on the surface of the copper metal develop a ________ charge by losing electrons and go into solution as copper(II) ions. Silver ions in solution, upon contacting the piece of copper metal, lose their positive charge by gaining electrons to form _______ that stick to the copper's surface.

calcium chloride and carbonic acid CaCl2(aq) + H2CO3(aq) CaCl2(aq) + H2O(l) + CO2(g)

calcium carbonate reacts with hydrochloric acid to form _______ and _________ CaCo3(s) + 2HCl(aq) ---> ______ + _____ net reaction: CaCo3(s) + 2HCl(aq) ---> ______ + ____ +_____

burned, oxygen

carbon dioxide has a higher oxygen:carbon atom ratio than does carbon monoxide. Carbon monoxide forms when carbon (coal), hydrocarbons, or other carbon-containing materials are _______ in the presence of insufficient__________. It is a colorless, odorless, poisonous gas. 2C(s) + O2(g) ---->2CO(g) It reacts further with oxygen to form colorless, odorless carbon dioxide, which is a component of the atmosphere and of exhaled breath: 2CO(g) + O2(g) ----> 2CO2(g)

smaller; larger

cations are _______ than neutral atoms while anion are ________ than neutral atoms

K, Ba, Sr, Ca, Na Mg, Al, Mn, Zn, Cr, Fe, Cd Co, Ni, Sn, Pb Sb, Bi, Cu, Ag, Hg, Pd, Pt, Au

chemical activity series: __,___,___,___,___ react with cold water to give H2 __,___,___,__,__,__,__ react with steam to give H2 ___,___,___,__ react with acids to give H2 H2 __,__,__,__,__,__,__,___ do not react to give H2

H2CO(g)

combine element with a compound to make a new compound: H2(g) + CO(g) ----> _____

Because we are given the mass of reactants, we must first convert from grams to moles for each reactant using their molar masses: moles of Al= 30.0g Al x (1 molAl/ 26.98g Al) = 1.11 mol Al moles of Br2= 45.0g Br2 x (1 molBr2/ 159.89g Br2) = 0.281 mol Br2 Next we determine the number of moles of one reactant needed to react with the other. Here we will determine the moles of Br2 needed to react with 1.11 mol Al: moles of Br2= 1.11mol Al x (3mol Br2/ 2 mol Al) = 1.67 mol Br2 We need 1.67 mol Br2, but we actually have only 0.281 mol Br2: Because Br2 is in short supply, it is the limiting reactant. To determine the mass of product, we can do a mass-mass conversion starting with the given grams of Br2. Or, we can start with the moles of Br2 calculated from the grams of Br2, convert moles of Br2 to moles of AlBr3, and then convert moles of AlBr3 to grams of AlBr3: mass of AlBr2= 0.281 mol Br2 x (2 mol AlBr3/ 3 mol Br2) x (266.7g AlBr3 / 1 mol AlBr3) = 50.0g AlBr3 The maximum amount of AlBr3 that can be produced is 50.0 g.

determine the limiting reactant when grams of reactants are given. When liquid bromine is mixed with aluminum metal, a combination reaction occurs, forming aluminum bromide: 2 Al(s) + 3Br2(l) ---> 2AlBr3(s) Determine the limiting reactant and mass of AlBr3 produced when 45.0 g of Br2 is added to 30.0 g of Al.

Cu(s) + ZnCl2(aq)

element react with compound to form a new compound and release an element from original compound: Zn(s) + CuCl2(aq) --->____ +_____

Pb2+(aq) + CrO4^2-(aq) --> PbCrO4(s)

eliminate the spectator ions from both sides of the ionic equation, to simplify the reaction and create the net ionic equation: Pb2+(aq)+ 2NO3-(aq) +2K+(aq)+ CrO4^2-(aq)-->PbCrO4(s)+ 2K+(aq)+2NO3-(aq)

Exothermic

energy released = _____ reaction

higher

fats have a much _____ energy value per gram than proteins or carbohydrates.

2 elements (or smaller compounds)

if the reactant is one compound, the product can be_______

sublevel; period; period number (row number) one less than the period number

if we follow the atomic symbols of the elements in the periodic table, we should be able to write an electron configuration for any element as we go. As we enter a new s, p, or d block, we know to change to a new _____. The principal energy level number n written before the sublevel letter is obtained from the ____ number. For the s and p blocks, n is the__________. For the d block, n is _______.

1.00 cal or 4.18 J of heat. 2.00 cal or 8.37 J of heat.

if we have a 1.00-g sample of water and we want to increase its temperature by 1.00°C, we must add _____ cal or _____ J of heat. Similarly, if we have a 2.00-g sample of water and want to increase its temperature by 1.00°C, we must add ____ cal or _____ J of heat.

Water

in a decomposition reaction, ______ is often produced when the reactant compound contains hydrogen and oxygen

dissolved in water

in a molecular equation, the aqueous physical state (aq) indicated for both reactants and one product indicates they are ___________

orbitals; sublevels

in an orbital diagram the boxes represent ______, and the groups of boxes represent ______.

their oxides

in combustion reactions, if reactants contain elements other than carbon, hydrogen, and oxygen, those elements are converted to ______-

all the H2 and O2; no reactants

in the combustion of hydrogen to form water: 2H2(g) + O2(g) ---> 2H2O(g) if the number of H2 molecules mixed is exactly two times the number of O2 molecules, then ________ molecules will react, and ________ will be left over.

gaseous water molecules, two hydrogen atoms and one oxygen atom.

in the reaction of hydrogen gas with oxygen gas, the reactants form the same product: __________ molecules, each containing two ______ atoms and one ______ atom.

decrease

increase in protons as you move across each period (move left to right) so effect of nuclear charge is going to ________ which means atomic size is going to ________

nonmetals

p-block elements with five p electrons are all in Group 7A (the halogens). All known halogens are _______.

(actual yield/theoretical yield) x 100

percent yield = _______________

a). = b). > c). <

steps for determining the limiting reactant: 1. Calculate the amount of one reactant (B) needed to react with the other reactant (A). 2. Compare the calculated amount of B (amount needed) to the actual amount of B that is present initially. a). if calculated B ____ actual B, there is no limiting reactant. Both A and B will react completely. b). if calculated B ___ actual B, B is the limiting reactant. only B will react completely c). if calculated B __ actual B, A is the limiting reactant. only A will react completely.

molecules of O2 = 8H2 molecules x (1 O2 molecule/ 2 H2 molecules) = 4 O2 molecules This calculation tells us that we need 4 O2 molecules to react with the 8 H2 molecules. We actually have 5 O2 molecules: calculated O2 < actual O2 We have 1 extra O2 molecule, so O2 is in excess. The H2 must be the limiting reactant. All 8 H2 molecules will react with 4 of the O2 molecules, and there will be 1 leftover O2 molecule.

suppose 8 molecules of H2 are mixed with 5 molecules of O2 and produce 8 H2O molecules. calculate the number of O2 molecules required to react with the 8 H2 molecules:

molecules of H2 = 5 O2 molecules x (2H2 molecules/ 1 O2 molecule) = 10 H2 molecules This calculation tells us that we need 10 H2 molecules to react with the 5 O2 molecules. Since we actually have only 8 H2 molecules, we know that calculated H2 > actual H2 Since there is not enough H2 to react with all the O2, H2 is the limiting reactant.

suppose 8 molecules of H2 are mixed with 5 molecules of O2 and produce 8 H2O molecules. determine the number of H2 molecules needed to react with the 5 O2 molecules:

the aufbau principle

the ________ states that electrons fill orbitals starting with the lowest-energy orbitals.

valence level, or valence shell

the ___________ contains orbitals that are larger than orbitals in lower principal energy levels.

5f orbitals

the actinide series (elements 90 to 103) corresponds to the filling of the ______ orbitals.

actual yield

the amount of product actually obtained in the laboratory from a reaction

3/5 or 3 mol CO2/ 5 mol O2

the balanced equation for the combustion of propane: C3H8(g) + 5O2(g) ---> 3CO2(g) + 4H2O(g) The equation also shows that the mole ratio of the product CO2 to the reactant O2 is ____ or ____

5/1 or 5 mol O2/ 1 mol C3H8 (This mole ratio tells us that 5 mol of O2 are needed for every 1 mol of C3H8 that reacts.)

the balanced equation for the combustion of propane: C3H8(g) + 5O2(g) ---> 3CO2(g) + 4H2O(g) so the mole ratio of O2 to C3H8 is ________ or _____

2H2(g) + O2(g) ---> 2H2O(g)

the combustion of hydrogen to form water: ____----> _____

Pb^2+(aq) + 2NO3-(aq)

the formula of Pb(NO3)2(aq) component ions.can be represented as:

theoretical yield

the maximum amount of product that can be obtained in a chemical reaction from known amounts of reactants; the amount of product calculated by assuming all the limiting reactant is consumed

solid aluminum bromide; Al3+ and Br− ; AlBr3 2Al(s) + 3Br2(l) ---> 2AlBr3(s)

the metal aluminum reacts with the nonmetal bromine to form __________. Because these elements form ions that we can predict from the periodic table (____ and _____), the correct formula for the product can be written (_______). Then we use coefficients to balance the equation: ____+_____----> _____

moles of Na = 0.20 mol Cl2 x (2 mol Na/ 1 mol Cl2) = 0.40 mol Na We need 0.40 mol Na, and we actually have 0.50 mol Na: calculated Na < actual Na therefore, Na is in excess by 0.10 mol and Cl2 must be the limiting reactant

the reaction of sodium metal and chlorine gas: 2 Na(s) + Cl2(g) ---> 2NaCl(s) Suppose we mix 0.50 mol Na with 0.20 mol Cl2. What is the limiting reactant? (a) begin by finding the moles of Na needed to react with the 0.20 mol Cl2:

2 Na(s) + Cl2(g) ---> 2NaCl(s)

the reaction of sodium metal and chlorine gas: ____ -->_____

Hund's rule

the third rule, _______: Electrons are distributed into orbitals of identical energy (same sublevel) in such a way as to give the maximum number of unpaired electrons.

d block; d orbitals

the transition metals are in the ____ block. Their highest-energy electrons are in ____ orbitals.

decomposition; combination(synthesis); single-displacement; double-displacement

there are four different patterns of reactivity, or reaction classes; chemists give them the following names: _____ reactions, _____ (or ______) reactions, ______ reactions, and ______ reactions.