Chemistry Review Between Quiz 1 & 2

What are the mass numbers for the two isotopes of nitrogen? nitrogen- nitrogen-

14 and 15

Select the correct electron configuration for Vanadium. (Atomic Number 23)

1s22s22p63s 23p64s23d3

Complete the following radioactive decay problem. 234 U --> 4 He + ? ? 92 2 ?

230 Th 90 (represents the atomic number, use it to find the element Th)

Which statement about reversible reactions is correct? At equilibrium, the forward and reverse reactions stop at the appropriate concentrations. At equilibrium, the forward and reverse reactions continue indefinitely. At equilibrium, the rate of reaction of the products divided by the rate of reaction of the reactants equals K.

At equilibrium, the forward and reverse reactions continue indefinitely.

Balance the following equation. ____ NaCl + ____ AgNO3 → ____ AgCl + ____NaNO3

Blank blank blank blank

Which compound is most difficult to decompose? CO CH4 NO2 NO

CO

Which element would have the greatest attraction for the calcium electrons (if they could combine)? N P As

N

The following list contains some common polyatomic ions. nitrate NO3 - phosphate (PO4)2- sulfate (SO4)2- acetate C2H3O2 - ammonium NH4 + chromate (CrO4)2- carbonate (CO3)2- dichromate (Cr2O7)2- permanganate MnO4 - sulfite SO3 2- Using the charge on these ions and the idea of valence, predict the formulas for the following: Sodium Carbonate -

Na2CO3

Give the symbol for the element that has an electron configuration of 1s22s22p63s23p4.

S

In a closed system containing three different gases, X2 + Y2 2XY, what MUST happen as the volume of the system is decreased at a constant temperature? The relative concentrations of each gas must change. The concentration of each gas will increase. The relative concentrations of each gas must remain constant. The concentration of each gas will not change.

The concentration of each gas will increase. The relative concentrations of each gas must remain constant.

What may be expected when K > 1.0? (Select all that apply.) The concentration of one or more of the reactants is small. The concentration of one or more of the products is small. The reaction will not proceed very far to the right. The reaction will proceed to the right and favor the formation of products.

The concentration of one or more of the reactants is small. The reaction will proceed to the right and favor the formation of products.

What causes the lines in the spectrum for elements?

a quantum release of energy as electrons drop back to their ground state

A quantum is a unit of:

energy

T/F A molecule's polarity is caused when the two nuclei making up the molecule are different sizes

false

T/F Electronegativity increases as the size of the atom increases

false

T/F The bonding of two different nonmetal elements together is accomplished by the metallic bond.

false

T/F In the following table, all the columns for the element beryllium are filled out correctly. Element Electron Structure of Atom Electron Structure of Ion Net Ion Charge Beryllium 1s1, 2s2 1s1 +2

false

Temperature is a measure of the internal bonding energy.

false

The splitting apart of atomic nuclei is known as ___.

fission

H2, N2, O2 molecules:

must be non-polar

The mass numbers for two isotopes are unequal because they have different numbers of ____

neutrons

The emission of a Beta particle has the effect of: (Select all that apply.) decreasing mass by one unit increasing mass by one unit no change in mass adding a proton to the nucleus

no change in mass adding a proton to the nucleus

When do electrons emit energy?

when moving to a lower orbit from an excited state

The Law of Multiple Proportions states that _____.

when two elements combine, A and B, the ratio of the weight of B combining with A is always a whole number

ΔH for the formation of CuCl2 from its elements is -220.1 kJ/mol. How many kJ are associated with the formation of 0.30 mole of CuCl2? -66 kJ -78 kJ 85 kJ 201 kJ

-66 kJ

A solution contains 180 g of glucose (C6H12O6) and 162 g of water. What is the mole fraction of glucose?

0.10

A 3.0 L solution contains 73.5 g of H2SO4. Calculate the molar concentration of the solution.

0.25 M

Match the atomic sublevel with the number of electrons that it holds. 1. s 2. p 3. d 4. f

1. 2 2. 6 3. 10 4. 14

1. helium nucleus emitted from the nucleus of a decaying isotope 2. an electron or particle similar to an electron emitted from the nucleus of a radioactive element 3. the nuclide produced from a radioactive decay 4. the number of protons plus neutrons in the nucleus 5. high energy ray emitted from some radioactive atoms 6. the difference between the mass of a nucleus and the sum of masses of its components; equivalent to binding 7. an isotope of a radioactive element 8. the beginning nuclide in the radioactive decay chain 9. unstable and capable of disintegrating into different elements, producing radiation and energy

1. alpha particle 2. beta particle 3. daughter 4. mass number 5. gamma ray 6. mass defect 7. nuclide 8. parent 9. radioactive

Match each word with its definition. 1. a measure of the ability of atoms to attract electrons within a chemical bond 2. the electron charge an atomic particle carries 3. a bond between atoms of greatly differing electronegativities, usually a metal and a nonmetal; a transfer of one or more valence electrons from one atom (low electronegativity) toward another (high electronegativity); bonds exist between unlike electrical charges (+ and - ions). 4. the bond formed in metals, holding metals together; delocalized bond with very fluid, mobile electrons; electron mobility accounts for ease of electrical conductivity 5. an unequal, unbalanced distribution of electrons in a molecule causing one portion to be partially positive (+) and another to be partially negative (-) 6. the measure of the degree of charge separation with a polar molecule

1. electronegativity 2. ion charge 3. ionic bond 4. metallic bond 5. polar 6. polarity

Match each word with its definition. 1. a reaction that absorbs energy 2. the energy in atoms and molecules that hold the substances together 3. a reaction that releases energy 4. the amount of heat released or absorbed by a reaction 5. the solid formed as a result of chemicals reacting together from a solution

1. endothermic 2. enthalpy 3. exothermic 4. heat of reaction 5. precipitate

1. the broad bands or regions located around the nucleus where the electrons are found 2. a vertical column of the periodic table 3. atom or group of atoms with a net charge 4. the energy necessary to overcome the attractions of electrons to the nucleus of an atom in order to remove the electron 5. a horizontal row in the periodic table 6. the distribution of light when passed through a prism

1. energy level 2. group 3. ion 4. ionization energy 5. period 6. spectrum

1. the number of protons plus neutrons in the nucleus 2. negative particles basic to matter 3. members of the same element (same atomic number) but different mass number 4. neutral particle found in the nucleus 5. the central core of the atom containing most of the mass 6. one of the particles of the nucleus; positively charged 7. energy available or given off in specific, predictable quantities

1. mass number 2. electrons 3. isotopes 4. neutron 5. nucleus 6. protons 7. quantum

Match the following polyatomic ions. 1. NO3- 2. (SO4)2- 3. NH4+ 4. (CO3)2- 5. MnO4- 6. (PO4)3- 7. C2H3O2- 8. (CrO4)2- 9. (Cr2O7)2- 10. SO32-

1. nitrate 2. sulfate 3. ammonium 4. carbonate 5. permanganate 6. phosphate 7. acetate 8. chromate 9. dichromate 10. sulfite

Match each word with its definition. 1. a dynamic state where two opposing forces are in balance, where two opposite events are occurring at equal rates 2. the substance dissolved in a solution 3. the component of a solution which dissolves the solute

1. solute 2. solvent 3. equilibrium

In the important industrial process for producing ammonia (the Haber Process), the overall reaction is: N2(g) + 3H2(g) → 2NH3(g) + 24,000 calories A yield of ammonia, NH3, of approximately 98% can be obtained at 200°C and 1,000 atmospheres of pressure. How many grams of N2 must react to form 1.7 grams of ammonia? 0.52 g 0.71 g 1.4 g 2.8 g

1.4 g

The equilibrium system N2O4(g) 2NO2(g) was established in a 1.00-liter vessel. Upon analysis, the following information was found: [NO2] = 0.5 M; [N2O4] = 0.025 M. Calculate the numerical value for the Keq of the N2O4 2NO2 system. Keq = ____

10

Complete the following radioactive decay problem. 238 Np --> 0 e + ? ? 93 -1 ?

238 Pu 94

Consider the following energy diagram. How much is the activation energy? ________ kcal/mole

43.8

Give the number of valence electrons for fluorine.

7

What is the atomic number of the two isotopes of nitrogen?

7

The bonding of two atoms will most likely occur if: A more stable state can result from the union. The outer shell can be completely filled. All the balance electrons are removed. The electronegativities of both atoms are similar.

A more stable state can result from the union.

Predict the following chemical formulas. Calcium Chloride -

CaCL2

If D+2 would react with E-1, what do you predict to be the formula? D2E DE2 D2E2 2DE

DE2

How is E related to a group of elements?

E decreases from top to bottom.

How is E related to a period of elements?

E generally decreases from right to left.

What is meant by "the energy of an electron is quantized"?

Each electron around an atom has a discrete measure of energy.

The most stable compound(s) shown is: C(g) N2 H2O(g) NH3(g)

H2O(g)

A company desires to produce nickel by refining nickel oxide and sulfide ores. The first step of the process will produce a nickel carbonyl gas, Ni(CO4), by heating the ore. The second step is as follows: Ni(CO4)(s) Ni(s) + 4CO(g) Using the principle of mass action, how would you accelerate the production of Ni? (Select all that apply.) Reduce the concentration of NiCO4. Increase the concentration of NiCO4. Withdraw Ni from the products as it is forming. Add CO to the reaction.

Increase the concentration of NiCO4. Withdraw Ni from the products as it is forming.

A company desires to produce nickel by refining nickel oxide and sulfide ores. The first step of the process will produce a nickel carbonyl gas, Ni(CO4), by heating the ore. The second step is as follows: Ni(CO4)(g) Ni(s) + 4CO(g) What effect on the process would be caused by increasing pressure? Ni would be produced at a higher rate. Ni would be produced at a lower rate. There would be no effect on this particular reaction.

Ni would be produced at a lower rate.

Select all that apply. What factors may be responsible for the ionization energy within a period? The valence electrons are further from the nucleus when moving from left to right. The valence electrons remain at the same distance from the nucleus when moving left to right. The diameter of the atom decreases somewhat as electrons are added. The attractive force of the nucleus increases.

The diameter of the atom decreases somewhat as electrons are added. The attractive force of the nucleus increases.

What factors may be responsible for the ionization energy within a period? The valence electrons are farther from the nucleus when moving from left to right. The valence electrons remain at the same distance from the nucleus when moving from left to right. The diameter of the atom decreases somewhat as electrons are added. The attractive force of the nucleus increases.

The diameter of the atom decreases somewhat as electrons are added. The attractive force of the nucleus increases.

Which statements are correct about a group? (Select all that apply.) The elements in each group have similar chemical properties. The elements in each group have identical physical properties. The atomic number of each element increase by 7 down through the group. Each member of the group has the same number of electrons in the outer shell.

The elements in each group have similar chemical properties. Each member of the group has the same number of electrons in the outer shell.

Why is the BrCl molecule polar? The shared electrons are closer to Cl due to the greater electronegativity of chlorine. Bromine has a large positive nucleus. Three dimensional geometry is asymmetrical. Chlorine gains an electron, whereas bromine loses one.

The shared electrons are closer to Cl due to the greater electronegativity of chlorine.

Why does electronegativity decrease down a family? The sizes of the atoms increase. The sizes of the atoms decrease. The total positive charge increases. The total positive charge decreases.

The sizes of the atoms increase.

What is true about the elements of a period? (Select all that apply.) They have the same number of electron shells. They have similar chemical characteristics. They have similar physical characteristics. They transition from a metal to nonmetal to inert gas from left to right.

They have the same number of electron shells. They transition from a metal to nonmetal to inert gas from left to right.

What is happening when the reactants BEGIN to react? (Select all that apply.) [A] + [B] decrease slowly. [A] + [B] decrease rapidly. [A] + [B] remain constant. [CD] decreases slowly. [CD] increases slowly. [CD] increases rapidly.

[A] + [B] decrease rapidly. [CD] increases rapidly.

If this reaction is exothermic, what may be expected as the temperature is reduced? [Products] will decrease. [Products] will increase. [Reactants] will increase. A reduction in temperature has no effect.

[Products] will increase.

What is happening after Time (Te)? [A] + [B] = [CD] [reactants] > [products] [reactants] < products] [A] + [B] remain constant. [Products] remain constant.

[reactants] > [products] [A] + [B] remain constant. [Products] remain constant.

Where does the energy come from in a fusion reaction?

a small amount of mass being converted to energy

The minimum energy required to start a reaction is called the:

activation energy

Catalysts can save money by essentially lowering the: (Select all that apply.) activation energy cost of reactants rate of reaction temperature required starting enthalpy (E1)

activation energy temperature required

What caused the bonding of two atoms which underwent an ionic bond? interlocking of mutual electrons attraction between electron cloud and nuclei attraction of opposite ions to each other sharing of outer shell

attraction of opposite ions to each other

Balance the following equation. ____ MgCl2 + ____ AgNO3 → ____AgCl + ____Mg(NO3)2

blank 2 2 blank

Which of the following is NOT an indicator of a chemical change? color change change in volume temperature change gas formation

change in volume

Diatomic molecules of gases at room temperature are due to _________ bonds. ionic covalent metallic none of the above

covalent

What is the nuclear product of radioactive decay called?

daughter

Consider the following reactions. ½H2(g) + ½I2(g) → HI(g), ΔH = + 26 kJ/mole 117 kJ/mole + C(s) + 2S(s) → CS2(g) The temperature of the surroundings will: increase decrease

decrease

Match the associations. positive change in H: products have less energy than reactants: E1 < E2: external energy required: negative change in H: products have greater energy than reactants: bond energy released

endo exo endo endo exo endo exo

The reaction producing nickel is as follows: Ni(CO4)(s) + Heat Ni(s) + 4CO(g) The reaction from left to right is ___ and therefore the addition of heat will ___ the production of nickel.

endothermic accelerate

Heat is a measure of .

energy

Consider the following reactions. (Note: letters (s), (l), and (g) indicate the states of matter of the components.) Mg(s) + ½O2(g) → MgO(s) + 601 kJ/mole H2(g) + ½O2(g) → H2O(g) ΔH = -242 kJ/mole What type of reaction is represented by the previous two examples?

exothermic

Enthalpy of a substance can be measured directly.

false

The combining of atoms together is known as nuclear ___.

fusion

A vertical column within the periodic table represents a ___

group

An electron: (Select all that apply.) has a negative charge is found in the nucleus emits energy when it moves to a lower energy orbit from an excited state has the same mass as a proton

has a negative charge emits energy when it moves to a lower energy orbit from an excited state

What is the significance of the discovery: E = mc2?

mass can be converted into energy

Which group, metals or nonmetals, has the greatest chance to gain electrons and to become negative ions?

nonmetals

Diatomic molecules will be ____ when they are composed of only one element

nonpolar

What is an unstable nucleus that starts a decay process called?

parent

A horizontal row of elements in the periodic table represents a _________

period

Which substances in the diagram are most unstable? positive values of enthalpy negative values of enthalpy negative values -50 to -100 values near zero

positive values of enthalpy

When a solid compound is formed from chemicals which are in solution, it is called a ___

precipitate

Two isotopes have the same number of _____ within the nucleus.

protons

ΔH for the formation of CuCl2 from its elements is -220.1 kJ/mol. When 0.30 mole of CuCl2 is formed: Energy will be released. Energy will be required.

released

Reactions which do not continue to completion are called ____ reactions.

reversible

A measure of the average kinetic energy of particle motion within a substance is

temperature

When the products of a reaction are hotter than the reactants: (Select all that apply.) the reaction is exothermic the reaction is endothermic the reactants lose internal energy as they became products the change in enthalpy is positive

the reaction is exothermic the reactants lose internal energy as they became products

In the following table, all the columns for the element nitrogen are filled out correctly. Element Electron Structure of Atom Electron Structure of Ion Net Ion Charge Nitrogen 1s2, 2s2, 2p3 1s2, 2s2, 2p6 -3

true

T/F A group of dissimilar elements with a net charge remaining is called a polyatomic ion.

true

The Periodic Law states that the physical and chemical properties of the elements are periodic within the sequence of their atomic numbers.

true

The outermost electrons in an atom are called _____ electrons.

valence