Chemistry 9th grade final review

1 Cheese + 2 Bread --> 1 Grilled cheeseHow many grilled cheeses can you make with 26 slices of bread and 14 pieces of cheese?

13

What is the atomic mass of "F"

19

Which electron configuration belongs to Chlorine (Cl)?

1s2 2s2 2p6 3s2 3p5

What electron configuration matches an oxygen atom?

1s22s22p4

How many electrons can the s sublevel hold?

2

Mg + ___ HCl → MgCl2 + H2

2

2H2 + O2 → 2H2OHow many moles of oxygen are consumed if 8 moles H2 are used?

4

How many atoms of aluminum are on each side of the following equation: 4Al + 3O2 --> 2Al2 O3

4

The Formula to make S'mores is:2C + 1M + G2 → C2MG2. If you have 5 Marshmallows (M), 9 Chocolate Pieces (C), and 9 Graham Cracker Halves (G), how many S'mores can you make?

4

CH4 + 2 O2 → CO2 + 2 H2OHow many moles of carbon dioxide are produced from the combustion of 110 g of CH4?

6.85 mol

Cl: How many valence electrons in this structure?

7

How many atoms are there TOTAL in:H2SO4

7

What is the number of protons that the element in this image contain?

7

SiO2 + 3C → SiC + 2COI need to add 8 moles of Carbon to the reaction. How many grams of Carbon should I weigh?

96 g

Generally, the number of neutrons ____ the number of protons in an atom.

=

The element with the lowest electronegativity in Period 3 is -

Ar

Atoms joined together by SHARING electrons are?

Covalent bonds

List the following in order of weakest to strongest ionization energy.P, Cs, Co, Sr

Cs, Sr, Co, P

2Pb(NO3)2 --> 2PbO + 4NO2 + O2

Decomposition

One reactant into several products.

Decomposition

What type of chemical reaction is this?Al(OH)3 → Al2O3 + H2O

Decomposition

Define a liquid.

Definite volume, indefinite shape

When a gas changes directly to a solid, the process is known as what?

Deposition

Ions in two compounds switch.

Double Replacement

The following is what type of reaction:PbCl2 + AgNO3 → Pb(NO3)2 + AgCl

Double Replacement

3KOH + H3PO4 --> K3PO4 + 3H2O

Double displacement

What does the Law of Conservation of Mass state?

Matter cannot be gained or lost in a chemical reaction.

Who developed the Periodic Table?

Mendeleev, who was a chemist and teacher

Which type of bond creates a "pool" of electrons between atoms?

Metallic Bonds

What is the limiting reactant if 10 moles of NH3 react with 30.0 moles of NO?4 NH3+6 NO --> 5 N2 + 6 H2O

NH3

Covalent compounds

Share electrons

As you move down the periodic table atoms get bigger. This is because ____________.

The atoms have more energy levels

Calculate the number of moles of Al2O3 that are produced when 0.60 mol of Fe is produced in the following reaction.2Al(s)+3FeO(s)->3Fe(s)+Al2O3(s)a. 0.20b. 0.40c. 0.60d. 0.90

a. 0.20 mol 0.60molFe*1molAl2O3/3molFe=0.20 mol Al2O3

How are covalent bonds explained?

When the atom shares an electron with an another atom

When does a chemical reaction stop?

When the limiting reactant is used up.

How many moles of H3PO are produced when 71g P4O10 reacts completely to form H3PO4?a. 0.635 molb. 1.00 molc. 4.00 mold. 16.0 mol

b. 1 mol

Which of the following statements is true about the following reaction? 3NaHCO3(aq) + C6H8O7(aq) --> 3CO2(g) + 3H2O(s) +Na3C6H5O7(aq)a. 22.7 L of CO2 (g) are produced for every liter of C6H8O7 (aq) reactedb. 1 mole of water is produced for every mole of carbon dioxide producedc. 6.02 x 10^23 molecules of Na3C6H5O7 (aq) are produced for every NaHCO3 (aq) usedd. 54 g of water are produced for every mole of NaHCO3 (aq) produced

b. 1 mole of water is produced for every mole of carbon dioxide produced

Metallic copper is formed when aluminum reacts with copper(II) sulfate. How many grams of metallic copper can be obtained when 54.0 g of Al react with 319 g of CuSO4 ? Al + 3CuSO4--> Al2 (SO4 )3+ 3Cu

b. 127 g

How many liters of NH3, at STP, will react with 5.3g of 02 to form NO2 and water.?

b. 2.12 liters of NH3

What atom matches this electron configuration?1s22s22p63s23p64s23d10

Zinc

Choose the correct shortcut configuration for iodine.

[Kr]5s24d105p5

How many liters of NH3 are needed to react completely with 30.0 L of NO (at STP)? 4HN3(g) + 6NO(g) ----> 5H2(g) +6H2O(g)a. 5.0 Lb. 20.0 Lc. 7.5 Ld. 120.0 L

b. 20.0 L

Iron(III) oxide is formed when iron combines with oxygen in the air. How many grams of Fe2O3 are formed when 16.7 g of Fe reacts completely with oxygen? 4Fe(s) + 3O2(g) --> 2Fe2O3(s)a. 12.0 gb. 23.9 gc. 47.8 gd. 95.6 g

b. 23.9g

When balancing equations a ____ can be placed to the left of a formula of a substance to make the equations balanced

coefficient

The summary at the end of an experiment that explains the results.

conclusion

How many liters of hydrogen gas are needed to react with CS2 to produce 2.50 L of CH4 at STP?4H2(g)+CS2(l) = CH4(g) +2H2S(g)a. 2.50 Lb. 5.00 Lc. 7.50 Ld. 10.0

d. 10.0 L

Hydrogen gas is produced when zinc reacts with hydrochloric acid. If the actual yield of this reaction is 85%? how many grams of zinc are needed to produce 112 l of H2 at STP?

d. 380

How many grams of H3PO4 are produced when 10.0 moles of water react with an excess of P4O10 ? P4O10 (s) + 6H2O(l) --> 4H3PO4 (aq)a. 1.22 gb. 6.7 gc. 147 gd. 653 g

d. 653 g

When glucose is consumed, it reacts with oxygen in the body to produce carbon dioxide, water, and energy. How many grams of carbon dioxide would be produced if 45 g of C6H12O6 completely reactedwith oxygen?a. 1.5 gb. 1.8 gc. 11 gd. 66 g

d. 66 g

The tendency of an atom to attract electrons and acquire a negative charge

electronegativity

Valence electrons are the number of

electrons in the outside shell of the atom

The energies of electrons as they orbit the nucleus of an atom

energy levels

What happens when my glass of water is sitting in the sun and disappears into a gas?

evaporation

Testing a hypothesis often involves a(n):

experiment

Which atom has the largest atomic radius?

francium

______________________ takes place when a liquid changes to a solid.

freezing

Particles (molecules) in a ______________________ have more energy than the other states of matter.

gas

Electronegativity is...

how good an atom is at attracting electrons

Ionization energy is...

how much energy it takes to remove an electron from an atom

A testable explanation to a problem that has not yet been tested.

hypothesis

As you look from left to right across a period, electronegativity

increases

Electronegativity __________ from left to right within a period and __________ from top to bottom within a group.

increases, decreases

This variable in an experiment is the one being changed by the scientist.

independent variable

A bond that forms when electrons are transferred is called a/an

ionic bond

The minimum energy required to remove an electron from the ground state of an atom

ionization energy

The limiting reactant . . .

is used up first.

Bonds that form between two metals are called ______________ bonds.

metallic

Which subatomic particle has a neutral or no charge?

neutron

Energy levels are denoted by:

numbers

You need 2 pieces of bread, 1 tablespoon of peanut butter and 2 tablespoons of jelly to make a sandwich. If you have 10 pieces of bread, 4 tablespoons of peanut butter and 20 tablespoons of jelly, what is the limiting reactant?

peanut butter

When electrons are shared unequally a/an ___________ bond is formed

polar covalent

Which subatomic particle has a positive charge?

proton

The atomic number of an elements is the total number of which particles in the nucleus?

protons

Which form of matter does not take the shape of its container?

solid

As you move across the periodic table atoms tend to get smaller because, ______________.

the atoms have more protons.

There are 4 different types of subshells (orbitals) s,p,d,f.

true

If an atom loses two electrons what charge will it have?

+ 2

If an atom gains one electron what charge will it have?

-1

Balance this equation._CF4 + _Br2 -- _CBr4 + _F2

1,2,1,2

Balance this equation._CH4 + _O2 --> _CO2 + _H2O

1,2,1,2

Balance this equation._SnO2 +_H2-->_Sn +_H2O

1,2,1,2

4 Al + 3 O2 -> 2 Al2O3 How much aluminum would be needed to completely react with 45 grams of O2?

1.875 moles

How many electrons can the d sublevel hold?

10

The electron configuration of an atom is 1s22s22p6. The number of electrons in the atom is

10

2 KClO3 → 2 KCl + 3 O2How many moles of oxygen are produced when 6.7 moles of KClO3 decompose completely?

10.1 mol

B2H6 + 3O2 -->2 HBO2 + 2 H2OWhat mass of O2 will be needed to burn 36.1 g of B2H6?

124 g O2

__ Al + __ FeO → Al2O2 + __ Fe

2, 2, 2

Balance this equation_Al +_HCl --> _H2 +_AlCl3

2, 6, 3, 2

Cl2 + 2 KBr → Br2 + 2 KClHow many grams of potassium chloride can be produced from 356 g of chlorine and 356 g of potassium bromide?

223 g

Which problem is balanced?

2Na + 2H2O --> 2NaOH + H2

which equation represents the reaction of sulfur with oxygen to form sulfur trioxide?

2S+3O2>2SO3

How many Valence electrons

3

For the Balanced Reaction: 3 Mg + 1 Fe2O3 → 3 MgO + 2 Fe; What is the Ratio of moles of MgO to moles Fe?

3 mol MgO / 2 mol Fe

PCl5 + ___ H2O → ___ HCl + H3PO4

4, 5

2Na + 2H2O → 2NaOH+ H2How many grams of hydrogen are produced if 120 g of Na are available?

5.2 g

2 NaClO3 (s) --> 2NaCl (s) +3 O2 (g)12.00 moles of NaClO3 will produce how many grams of O2?

576 g of O2

How many Valence electrons

6

How many atoms of carbon (C) are in C6H12O6?

6

What is the number of valence electrons for Oxygen?

6

an atom with atomic number 6 would have how many protons

6

Which periodic table family could have electrons filling orbitals in the s-block?

Alkaine Earth

Which of the following will have a lower ionization energy than Scandium (Sc)?

Calcium (Ca)

Which of the following will have a higher electronegativity than arsenic (As)?

Carbon (C)

Which of the following elements has the smallest atomic radius?

Chlorine

The electronegativity of Cl is the highest in Period 3. Why?

Cl is the smallest and has the greatest effective nuclear charge

Use the equation 2 Al + 3 Cl2 ---> 2 AlCl3. If 2 moles of aluminum and 2 moles of chlorine are reacted, identify the limiting reactant.

Cl2

Always starts with a Hydrocarbon that reacts with oxygen and produces carbon dioxide and water.

Combustion

C4H12 + O2 → CO2 + H2O

Combustion

Which subatomic particles contribute the least to the mass of an atom?

Electrons

What subatomic particle(s) would be found orbiting the nucleus?

Electrons only

The element with the largest electronegativity in the halogens is -

F

All chemical bonds involve two atoms sharing electrons.

False

The chemical bond formed when two atoms share electrons is called a(an) IONIC bond.

False

Which is NOT a step in the scientific method?

Form a theory

How is a gas defined?

Indefinite shape, indefinite volume

Which type of bond has a transfer of an electron from on atom to another?

Ionic

Which side of a chemical equation os the product side?

Right (after the yields sign)

What term describes a liquid changing to a solid?

Freezing

The state of matter that has no definite size or shape is

Gas

Identify the limiting reagent when 6.00 moles HCl combines with 5.00 moles Mg to form MgCl2.1 Mg + 2 HCl --> 1 MgCl2 + 1 H2

HCl

what happens to the temperature between points D and E

It remains the same.

Which side of a chemical equation is the reactant side?

Left (before the yields sign)

What atom matches this electron configuration?1s22s22p63s2

Magnesium

Which of the following has a full valence shell?

Neon

Is the equation balanced?: 2H2O + O2 --> 4MgO + 3Fe

No

Which type of bond has an equal sharing of electrons?

Non Polar Covalent

1 P4 + 3 O2 --> 1 P4O6What is the limiting reactant if 12 moles of P4 react with 15 moles of O2?

O2

Identify the limiting reagent and the volume of CO2 formed when 11L CS2 reacts with 18 L O2 to produce CO2 gas and SO2 gas at STP.CS2(g) + 3O2(g) --> CO2(g) + 2SO2(g)

O2; 6.0 L CO2

When 12 moles of O2 reacts with 6 moles of C10H8, what is the limiting reactant?1 C10H8 + 12 O2 --> 10 CO2 + 4 H2O

Oxygen

Which type of bond has an unequal sharing of electrons?

Polar Covalent

Elements on the LEFT side of the periodic table will most likely form:

Positive ions

Which subatomic particles contribute the most to the mass of an atom?

Protons and Neutrons

The two sides of a chemical equation are called?

Reactants (left) and Products (right)

3Ca + 2AlCl3 --> 3CaCl2 + 2Al

Single Displacement

One element replaces another in a compound.

Single Replacement

What type a reaction is taking place in this picture?

Single Replacement

Molecules are closest together in a

Solid

Which state of matter has the lowest compressibility?

Solid

What term describes a solid changing to a gas?

Sublimation

What is the little number after an element in a chemical equation called.Example: H2

Subscript

4Si + S8 --> 2Si2S4

Synthesis

The following is what type of reaction:NH3 + HCl → NH4Cl

Synthesis

Two Reactants and One Product

Synthesis

Water can be a solid, liquid, and a gas.

True

Which conversion factor do you use first to calculate the number of grams of CO2 produced by the reaction of 50.6 g of CH4 with O2 ? The equation for the complete combustion of methane is: CH4 (g) + 2O2 (g) --> CO2 (g) + 2H2O(l)a. 1 mol CH4/16.0 g CH4b. 2 mol O2/ 1 mol CO2c. 16.0g CH4/1 mol CO4d. 44.0g CO2/ 2 mol CO2

a. 1 mol CH4/16.0 g CH4

How many grams of chromium are needed to react with an excess of CuSO4 to produce 27.0g Cu?2Cr(s) + 3CuSO4(aq)---->Cr2(SO4)3(aq) + 3Cu(s)

a. 14.7 grams

Methane and hydrogen sulfide form when hydrogen reacts with carbon disulfide identify the excess reagent and calculate how much remains after 36 l of h2 reacts with 12 l of cs2 4 h2 g cs2 g ch4 g 2 h2s g

a. 3 L CS2

Which of the following would be the limiting reagent in the reaction shown below? 2H2(g) + O2(g) --> 2H2O(g)

a. 50 molecules of H2

Which statement is true if 12 mol CO and 12 mol Fe2O3 are allowed to react? 3CO (g) + Fe2O3 (s) ---> 2Fe (s) + 3CO2(g)

a. limiting reagent is CO and 8.0 mol Fe will be formed.

Each row on the periodic table represents:

an energy level

Particles of a liquid

are free to move around one another but still touch.

Where is the element's atomic MASS located?

at the bottom

all matter is made of what

atoms

How many liters of chlorine gas can be produced when 0.98 L of HCl react withexcess O2 at STP? 4HCl(g) + O2(g) -- >2Cl2 (g) + 2H2O(g)

b. 0.49 L

Aluminum reacts with sulfuric acid to produce aluminum sulfate and hydrogen gas. How many grams of aluminum sulfate would be formed if 250 g H2SO4 completely reacted with aluminum?2AL(s) + 3H2SO4 (aq) --> Al2 (SO4)3 (aq) + 3H2 (g)a. 0.85 gb. 290 gc. 450 gd. 870 g

b. 290 g

What is the maximum number of grams of PH3 that can be formed when 6.2 g ofphosphorus reacts with 4.0 g of hydrogen to form PH3 ? P4 (g) + 6H2(g) --> 4PH3 (g)

b. 6.8 g

Calcium oxide, or lime, is produced by the thermal decomposition of limestone in the reaction CaCO3 (s) --> CaO(s) + CO2(g). What mass of lime can be produced from 1.5 x 10^3 kg of limestone?a. 8.4 x 10^5 kgb. 8.4 x 10^2 kgc. 8.4 kgd. none of the above

b. 8.4 x10^2 kg

When two substances react to form products, the reactant used up is called what?a. determining reagentb. limiting reagentc. excess reagentd. catalytic reagent

b. limiting reagent

What is decomposition?

breaking substances apart

Mercury can be obtained by reacting mercury(II) sulfide with calcium oxide. How many grams of calcium oxide are needed to produce 36.0 g of Hg?4HgS(s) + 4CaO(s) -->4Hg(l) + 3CaS(s) + CaSO4a. 1.80 gb. 7.56 gc. 10.1 gd. 13.4 g

c. 10.1 g

How many grams of beryllium are needed to produce 36.0 g of hydrogen? (Assume anexcess of water.) Be(s) + 2H2O(l) --> Be(OH)2 (aq) + H2(g)

c. 162 g

n a particular reaction between copper metal and silver nitrate, 12.7 g Cu produced 38.1 g Ag. What is the percent yield of silver in this reaction?Cu + 2AgNO3--> Cu(NO3) 2 + 2Ag

c. 88.2%

Lead nitrate can be decomposed by heating. What is the percent yield of the decomposition reaction if 9.9 g Pb(NO3 )2 are heated to give 5.5 g of PbO?2Pb(NO3 )2(s) -->2PbO(s) + 4NO2(g) + O2 (g)

d. 82%

Glucose, C6H12O6, is a good source of food energy. When it reacts with oxygen, carbon dioxide and water are formed.How many liters of CO2 are produced when 126 grams of glucose completely react with oxygen? C6H12O6 (s) + 6 O2 --> 6 CO2 (g) + 6 H2O (l) = 673 kcala. 4.21 Lb. 5.33 Lc. 15.7 Ld. 94.1 L

d. 94.1 L

The name of the information that you get from your experiment (you organize it into charts and graphs).

data

Atomic radius generally increases as we move __________.

down a group and from right to left across a period

Which subatomic particle has a negative charge?

electron

What are the 3 subatomic particles of an atom?

protons, neutrons, electrons

A series of steps used by scientists to solve a problem or answer a question.

scientific method

Chemical bonds form when atoms

share or transfer electrons

Where is the element's atomic NUMBER located?

the top

An ionic bond forms when atoms ___________ electrons.

transfer

Which area on the periodic table represents the electrons in the "d" sublevel?

transition elements

Is this equation balanced?

yes

Which of the following is not a correct designation for a sublevel?

zz