Question 1

You have a sample of 3.01 × 1023 atoms of silver. How much does this sample weigh?

Accepted Answer

A)  0.0500 g 
B)  2.00 g 
C)  53.9 g 
D)  107.9 g

Question 2

Which of the following is the correct set of integer coefficients for the balanced equation, respectively: ___ CO2(g) + ___H2O(l) → ___C6H12O6(aq) + ___O2(g)

Accepted Answer

A)  1, 1, 1, 1 
B)  3, 3, 6, 6 
C)  6, 3, 3, 6 
D)  6, 6, 1, 6

Question 3

The atomic weight of copper is less than that of silver. If you have a 10 g sample of each of these metals, which of the following is true?

Accepted Answer

A)  You have fewer of atoms of copper than of silver. 
B)  You have equal numbers of atoms of copper and silver. 
C)  You have more atoms of copper than of silver. 
D)  There is insufficient information to determine which of the above is true.

Question 4

0.789 mol of a particular substance weighs 142 G) What is the molar mass of this substance?

Accepted Answer

A)  0.00556 g 
B)  0.00556 amu 
C)  180 g 
D)  180 amu

Question 5

What is the molar mass of water, H2O?

Accepted Answer

A)  17.01 g 
B)  18.02 g 
C)  17.01 amu 
D)  18.02 amu

Question 6

What is the formula weight ammonium carbonate, (NH4)2CO3?

Accepted Answer

A)  78.1 amu 
B)  96.1 amu 
C)  108.4 amu 
D)  138.2 amu

Question 7

Which of the following is oxidation?

Accepted Answer

A)  loss of electrons 
B)  loss of hydrogen 
C)  gain of oxygen 
D)  all of these

Question 8

Assume each of the containers in the image contains Avogadro's number of molecules of the substance pictured. 
-Which of the following correctly describes each container?

Accepted Answer

A)  Each contains the same mass. 
B)  Each contains the same volume. 
C)  Each contains the same number of moles 
D)  Each contains the same number of atoms. 
E)  Both c and d are correct.

Question 9

Which of the following is oxidation?

Accepted Answer

A)  gain of electrons 
B)  gain of hydrogen 
C)  loss of oxygen 
D)  none of these

Question 10

Ethyl chloride is prepared by the reaction of ethane with chlorine according to the reaction: 2 C2H6 (g) + Cl2(g) → C2H5Cl(l) + HCl(g)
The percent yield of ethyl chloride in one experiment was 96.3% and the actual yield was 74.4 G) How much ethylene did the chemist use in this experiment?

Accepted Answer

A)  36.0 g 
B)  38.7 
C)  70.9 g 
D)  77.3 g

Question 11

Which of the following is the correct set of integer coefficients for the balanced equation respectively: ___ C5H12(g) + ___O2(g) → ___CO2(g) + ___H2O(g)

Accepted Answer

A)  1, 5, 5, 6 
B)  1, 8, 5, 6 
C)  5, 1, 8, 6 
D)  5, 12, 2, 4

Question 12

When a solution of Cu(II) chloride, CuCl2 , is added to a solution of potassium sulfide, K2S, a black precipitate of copper sulfide, CuS, forms. Which of the following is the net ionic equation for this reaction?

Accepted Answer

A)  CuCl2(aq) + K2S(aq) → CuS(s) + 2 KCl(aq) 
B)  Cu2+(aq) + Cl22-(aq) + K22+(aq) + S2-(aq) → CuS(s) + K22+(aq) + Cl22-(aq) 
C)  Cu2+(aq) + 2 Cl-(aq) + 2 K+(aq) + S2-(aq) → CuS(s) + 2 K+(aq) + 2 Cl- (aq) 
D)  Cu2+(aq) + S2-(aq) → CuS(s)

Question 13

You have a sample of 1.204 × 1024 atoms of gold. How much does this sample weigh?

Accepted Answer

A)  2.000 g 
B)  98.5 g 
C)  197.0 g 
D)  394.0 g

Question 14

For the reaction N2(g) + 3 H2(g) → 2 NH3(g) which of the following can be determined using only the coefficients of the balanced chemical equation?

Accepted Answer

A)  the number of moles of NH3 obtained if 4.2 mol of N2 react completely to form NH3 
B)  the weight of NH3 obtained if 4.2 mol of N2 react completely to form NH3 
C)  both a and b 
D)  neither a nor b

Question 15

When solutions of H2SO4 and NaOH react, the balanced molecular equation is: H2SO4(aq) + 2 NaOH(aq) → Na2SO4(aq) + 2 H2O(l)
How much Na2SO4 is obtained when 4.00 g of H2SO4 reacts with 4.00 g of NaOH?

Accepted Answer

A)  2.98 g 
B)  5.80 g 
C)  7.10 g 
D)  8.00 g

Question 16

In a blast furnace, coke, which is solid carbon, reacts with O2(g) to form carbon monoxide. The carbon monoxide then reacts with Fe2O3(s) to produce solid iron and carbon dioxide. Which of the following is the balanced equation for the reaction of carbon monoxide with Fe2O3(s)?

Accepted Answer

A)  2 Fe2O3(s) + 3 CO(g) → 2 Fe(s) + 3 CO2(g) 
B)  2 Fe2O3(s) + 2 CO(g) → 4 Fe(s) + 2 CO2(g) 
C)  2 Fe2O3(s) + 3 CO(g) → 4 Fe(s) + 3 CO2(g) 
D)  Fe2O3(s) + 3 CO(g) → 2 Fe(s) + 3 CO2(g)

Question 17

The mass of an atom of 12C is exactly 12 atomic mass units. Which of the following describes a mole of 12C atoms?

Accepted Answer

A)  a sample which weighs exactly 12 atomic mass units 
B)  a sample which contains 6.02 × 1023 atoms of 12C 
C)  both a and b 
D)  neither a nor b

Question 18

O2 can be produced by the reaction 2 KClO3(s) → 2 KCl(s) + 3 O2(g). In one experiment 0.312 g of O2 was formed. How much KClO3 was decomposed?

Accepted Answer

A)  0.484 g 
B)  0.797 g 
C)  1.19 g 
D)  1.79 g

Question 19

Which of the following compounds has the largest formula weight?

Accepted Answer

A)  KCl 
B)  NaCl 
C)  MgF2 
D)  BF3

Question 20

The synthesis of a certain drug requires 3 steps. The percent yield for the steps are 95.2%, 91.4% and 93.8% respectively. What is the overall percent yield?

Accepted Answer

A)  81.6% 
B)  87.0% 
C)  89.3% 
D)  91.4%

Exam 4: Chemical Reactions

You have a sample of 3.01 × 10²³ atoms of silver. How much does this sample weigh?

Which of the following is the correct set of integer coefficients for the balanced equation, respectively: _ CO₂(g) + _H₂O(l) → _C₆H₁₂O₆(aq) + _O₂(g)

The atomic weight of copper is less than that of silver. If you have a 10 g sample of each of these metals, which of the following is true?

0.789 mol of a particular substance weighs 142 G) What is the molar mass of this substance?

What is the molar mass of water, H₂O?

What is the formula weight ammonium carbonate, (NH₄) ₂CO₃?

Which of the following is oxidation?

Assume each of the containers in the image contains Avogadro's number of molecules of the substance pictured. -Which of the following correctly describes each container?

Which of the following is oxidation?

Which of the following is the correct set of integer coefficients for the balanced equation respectively: _ C₅H₁₂(g) + _O₂(g) → _CO₂(g) + _H₂O(g)

When a solution of Cu(II) chloride, CuCl₂ , is added to a solution of potassium sulfide, K₂S, a black precipitate of copper sulfide, CuS, forms. Which of the following is the net ionic equation for this reaction?

You have a sample of 1.204 × 10²⁴ atoms of gold. How much does this sample weigh?

For the reaction N₂(g) + 3 H₂(g) → 2 NH₃(g) which of the following can be determined using only the coefficients of the balanced chemical equation?

When solutions of H₂SO₄ and NaOH react, the balanced molecular equation is: H₂SO₄(aq) + 2 NaOH(aq) → Na₂SO₄(aq) + 2 H₂O(l) How much Na₂SO₄ is obtained when 4.00 g of H₂SO₄ reacts with 4.00 g of NaOH?

In a blast furnace, coke, which is solid carbon, reacts with O₂(g) to form carbon monoxide. The carbon monoxide then reacts with Fe₂O₃(s) to produce solid iron and carbon dioxide. Which of the following is the balanced equation for the reaction of carbon monoxide with Fe₂O₃(s) ?

The mass of an atom of ¹²C is exactly 12 atomic mass units. Which of the following describes a mole of ¹²C atoms?

O₂ can be produced by the reaction 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g) . In one experiment 0.312 g of O₂ was formed. How much KClO₃ was decomposed?

Which of the following compounds has the largest formula weight?

The synthesis of a certain drug requires 3 steps. The percent yield for the steps are 95.2%, 91.4% and 93.8% respectively. What is the overall percent yield?

Exam 4: Chemical Reactions

You have a sample of 3.01 × 1023 atoms of silver. How much does this sample weigh?

Which of the following is the correct set of integer coefficients for the balanced equation, respectively: ___ CO2(g) + ___H2O(l) → ___C6H12O6(aq) + ___O2(g)

The atomic weight of copper is less than that of silver. If you have a 10 g sample of each of these metals, which of the following is true?

0.789 mol of a particular substance weighs 142 G) What is the molar mass of this substance?

What is the molar mass of water, H2O?

What is the formula weight ammonium carbonate, (NH4) 2CO3?

Which of the following is oxidation?

Assume each of the containers in the image contains Avogadro's number of molecules of the substance pictured. -Which of the following correctly describes each container?

Which of the following is oxidation?

Ethyl chloride is prepared by the reaction of ethane with chlorine according to the reaction: 2 C2H6 (g) + Cl2(g) → C2H5Cl(l) + HCl(g) The percent yield of ethyl chloride in one experiment was 96.3% and the actual yield was 74.4 G) How much ethylene did the chemist use in this experiment?

Which of the following is the correct set of integer coefficients for the balanced equation respectively: ___ C5H12(g) + ___O2(g) → ___CO2(g) + ___H2O(g)

When a solution of Cu(II) chloride, CuCl2 , is added to a solution of potassium sulfide, K2S, a black precipitate of copper sulfide, CuS, forms. Which of the following is the net ionic equation for this reaction?

You have a sample of 1.204 × 1024 atoms of gold. How much does this sample weigh?

For the reaction N2(g) + 3 H2(g) → 2 NH3(g) which of the following can be determined using only the coefficients of the balanced chemical equation?

When solutions of H2SO4 and NaOH react, the balanced molecular equation is: H2SO4(aq) + 2 NaOH(aq) → Na2SO4(aq) + 2 H2O(l) How much Na2SO4 is obtained when 4.00 g of H2SO4 reacts with 4.00 g of NaOH?

In a blast furnace, coke, which is solid carbon, reacts with O2(g) to form carbon monoxide. The carbon monoxide then reacts with Fe2O3(s) to produce solid iron and carbon dioxide. Which of the following is the balanced equation for the reaction of carbon monoxide with Fe2O3(s) ?

The mass of an atom of 12C is exactly 12 atomic mass units. Which of the following describes a mole of 12C atoms?

O2 can be produced by the reaction 2 KClO3(s) → 2 KCl(s) + 3 O2(g) . In one experiment 0.312 g of O2 was formed. How much KClO3 was decomposed?

Which of the following compounds has the largest formula weight?

The synthesis of a certain drug requires 3 steps. The percent yield for the steps are 95.2%, 91.4% and 93.8% respectively. What is the overall percent yield?

You have a sample of 3.01 × 10²³ atoms of silver. How much does this sample weigh?

Which of the following is the correct set of integer coefficients for the balanced equation, respectively: _ CO₂(g) + _H₂O(l) → _C₆H₁₂O₆(aq) + _O₂(g)

What is the molar mass of water, H₂O?

What is the formula weight ammonium carbonate, (NH₄) ₂CO₃?

Which of the following is the correct set of integer coefficients for the balanced equation respectively: _ C₅H₁₂(g) + _O₂(g) → _CO₂(g) + _H₂O(g)

When a solution of Cu(II) chloride, CuCl₂ , is added to a solution of potassium sulfide, K₂S, a black precipitate of copper sulfide, CuS, forms. Which of the following is the net ionic equation for this reaction?

You have a sample of 1.204 × 10²⁴ atoms of gold. How much does this sample weigh?

For the reaction N₂(g) + 3 H₂(g) → 2 NH₃(g) which of the following can be determined using only the coefficients of the balanced chemical equation?

When solutions of H₂SO₄ and NaOH react, the balanced molecular equation is: H₂SO₄(aq) + 2 NaOH(aq) → Na₂SO₄(aq) + 2 H₂O(l) How much Na₂SO₄ is obtained when 4.00 g of H₂SO₄ reacts with 4.00 g of NaOH?

In a blast furnace, coke, which is solid carbon, reacts with O₂(g) to form carbon monoxide. The carbon monoxide then reacts with Fe₂O₃(s) to produce solid iron and carbon dioxide. Which of the following is the balanced equation for the reaction of carbon monoxide with Fe₂O₃(s) ?

The mass of an atom of ¹²C is exactly 12 atomic mass units. Which of the following describes a mole of ¹²C atoms?

O₂ can be produced by the reaction 2 KClO₃(s) → 2 KCl(s) + 3 O₂(g) . In one experiment 0.312 g of O₂ was formed. How much KClO₃ was decomposed?