Question 1

In the complete combustion of C3H8O3,how many moles of carbon dioxide are produced when 23.0 g of C3H8O3 burns?

Accepted Answer

A)  0.250 mol
B)  0.750 mol
C)  0.0833 mol
D)  3.00 mol
E)  33.0 mol B

Question 2

When 1.00 g of C6H12O6(s)is formed during photosynthesis,15.67 kJ of the sun's energy is converted to chemical energy.What is the thermochemical equation for the photosynthesis of glucose?

Accepted Answer

A)  6 CO2(g)  + 6 H2O(g)  → C6H12O6(s)  + 6 O2(g)  + 15.67 kJ
B)  CO2(g)  + H2O(g)  → C6H12O6(s)  + O2(g)  ?0?H = 15.67 kJ
C)  6 CO2(g)  + 6 H2O(g)  + 2.82 × 103 kJ → C6H12O6(s)  + 6 O2(g) 
D)  C6H12O6(s)  + 6 O2(g)  → 6 CO2(g)  + 6 H2O(g)  + 2.82 × 103 kJ
E)  6 CO2(g)  + 6 H2O(g)  → C6H12O6(s)  + 6 O2(g)  ?0?H = -2.82 × 103 kJ C

Question 3

1.90 × 103 J of heat,in combination with high pressure,are needed to transform one mole of the graphite form of carbon into the diamond form.How many kilocalories is this?

Accepted Answer

A)  0.0378 kcal
B)  0.454 kcal
C)  454 kcal
D)  1.90 kcal
E)  7.95 kcal B

Question 4

PCl5 can be produced by the reaction PCl3 + Cl2 → PCl5.What mass of PCl3 must be used to produce 127 g of PCl5 if the percent yield is 84.8%?

Accepted Answer

A)  71.1 g
B)  83.8 g
C)  98.8 g
D)  108 g
E)  150 g

Question 5

How much energy is required to produce 1.00 kg of aluminum by the reaction 
2 Al2O3(s)+ 3 C(s)+ 1.97 × 103 kJ → 4 Al(s)+ 3 CO2(g)?

Accepted Answer

A)  5.50 × 10-5 kJ
B)  7.52 × 10-2 kJ
C)  2.70 × 103 kJ
D)  7.30 × 104 kJ
E)  1.83 × 104 kJ

Question 6

How many moles of bromine will react with 0.0500 mole of C2H2 in the reaction C2H4 + Br2 → C2H4Br2?

Accepted Answer

A)  0.100 mol
B)  0.186 mol
C)  0.0250 mol
D)  0.0500 mol
E)  2.00 mol

Question 7

The decomposition of potassium chlorate is written as shown below.What energy change occurs when 12.3 g of KClO3 decompose? 
2 KClO3(s)+ 89.6 kJ → 2 KCl(s)+ 3 O2(g)

Accepted Answer

A)  Release of 8.99 kJ
B)  Absorption of 8.99 kJ
C)  Release of 4.49 kJ
D)  Absorption of 4.49 kJ
E)  Release of 0.00112 kJ

Question 8

A chemist combines hydrochloric acid with a sodium hydroxide solution,transferring 5.75 kJ of heat.Express this in calories.

Accepted Answer

A)  2.41 × 10-2 cal
B)  2.41 × 101 cal
C)  2.41 × 104 cal
D)  1.37 × 10-3 cal
E)  1.37 × 103 cal

Question 9

The reaction C6H6 + HNO3 → C6H5NO2 + H2O has a 73.5 percent yield under certain conditions.If 12.75 g of C6H6 is used,how much C6H5NO2 will be produced?

Accepted Answer

A)  20.1 g
B)  27.4 g
C)  8.09 g
D)  11.0 g
E)  14.8 g

Question 10

Calculate the mass of Na2O that can be produced by the reaction of 4.00 g of sodium and 2.00 g of oxygen in the reaction 4 Na + O2 → 2 Na2O.

Accepted Answer

A)  1.94 g
B)  2.00 g
C)  4.50 g
D)  5.39 g
E)  6.00 g

Question 11

When C2H5Cl(g)is burned in oxygen,chlorine gas is produced in addition to carbon dioxide and water vapor.5145 kJ of heat are released for every four moles of C2H5Cl(g)burned.Which of the following correctly represents the thermochemical equation?

Accepted Answer

A)  4 C2H5Cl(g)  + 5145 kJ + 13 O2(g)  → 2 Cl2(g)  + 8 CO2(g)  + 10 H2O(g) 
B)  4 C2H5Cl(g)  + 13 O2(g)  + 5145 kJ → 2 Cl2(g)  + 8 CO2(g)  + 10 H2O(g) 
C)  4 C2H5Cl(g)  + 13 O2(g)  → (5145 kJ)  → 2 Cl2(g)  + 8 CO2(g)  + 10 H2O(g) 
D)  4 C2H5Cl(g)  + 13 O2(g)  → 2 Cl2(g)  + 8 CO2(g)  + 10 H2O(g)  ?0?H = +5145 kJ
E)  4 C2H5Cl(g)  + 13 O2(g)  → 2 Cl2(g)  + 8 CO2(g)  + 10 H2O(g)  ?0?H = -5145 kJ

Question 12

Consider the conversion diagram given below.  At which point(s)in the diagram is a molar mass needed?

Accepted Answer

A)  A and B
B)  B and E
C)  A and D
D)  D and E
E)  C only

Question 13

The metabolism of glucose can be represented by the equation C6H12O6(s)+ 6 O2(g)→ 6 CO2(g)+ 6 H2O(g)ΔH = -2.82 × 103 kJ.How many grams of glucose must be metabolized to produce 282 kJ of energy?

Accepted Answer

A)  18.0 g
B)  1.80 × 102 g
C)  0.100 g
D)  10.0 g
E)  67.4 g

Question 14

How many moles of C6H12O6 are formed when 0.250 mole of CO2 is consumed in the reaction 6 CO2 + 6 H2O → C6H12O6 + 6 O2?

Accepted Answer

A)  1.50 mol
B)  1.00 mol
C)  0.250 mol
D)  0.167 mol
E)  0.0417 mol

Question 15

Which of the following defines the percent yield for a reaction?

Accepted Answer

A)   
B)   
C)   
D)

Question 16

Aqueous HCl is added to an aqueous solution of NaOH at 25 °C and the result is shown in the figure below.  Which of the following correctly characterizes this reaction?

Accepted Answer

A)  The reaction is exothermic.
B)  The ΔH for the reaction has a + sign.
C)  Energy could be considered to be a reactant in the equation for the reaction.
D)  The energy (enthalpy)  of the products is greater than the reactants.
E)  This reaction consumes energy.

Question 17

A typical candy bar contains 281 food Calories,which is 281 kcal.How many kilojoules are contained in one such candy bar?

Accepted Answer

A)  1.18 × 103 kJ
B)  1.18 × 104 kJ
C)  67.2 kJ
D)  672 kJ
E)  6.72 × 104 kJ

Question 18

How many moles of oxygen are consumed in the complete combustion of 1.60 moles of benzene,C6H6?

Accepted Answer

A)  6.00 mol
B)  12.0 mol
C)  15.0 mol
D)  18.0 mol
E)  24.0 mol

Question 19

When one mole of gaseous hydrogen peroxide,H2O2,is made from hydrogen and oxygen gases,the enthalpy change is -136 kJ.Which of the following correctly represents the thermochemical equation?
i.H2(g)+ O2(g)→ H2O2(g)+ 136 kJ
ii.H2(g)+ O2(g)+ 136 kJ → H2O2(g)
iii.H2(g)+ O2(g)→ H2O2(g) ΔH = -136 kJ
iv.H2(g)+ O2(g)→ H2O2(g) ΔH = +136 kJ

Accepted Answer

A)  i only
B)  ii only
C)  iii only
D)  i and iii
E)  ii and iv

Question 20

Convert 357 J to kcal.

Accepted Answer

A)  1.49 kcal
B)  1.49 × 106 kcal
C)  8.53 × 104 kcal
D)  85.3 kcal
E)  0.0853 kcal

Exam 10: Quantity Relationships in Chemical Reactions

In the complete combustion of C₃H₈O₃,how many moles of carbon dioxide are produced when 23.0 g of C₃H₈O₃ burns?

When 1.00 g of C₆H₁₂O₆(s) is formed during photosynthesis,15.67 kJ of the sun's energy is converted to chemical energy.What is the thermochemical equation for the photosynthesis of glucose?

1.90 × 10³ J of heat,in combination with high pressure,are needed to transform one mole of the graphite form of carbon into the diamond form.How many kilocalories is this?

PCl₅ can be produced by the reaction PCl₃ + Cl₂ → PCl₅.What mass of PCl₃ must be used to produce 127 g of PCl₅ if the percent yield is 84.8%?

How much energy is required to produce 1.00 kg of aluminum by the reaction 2 Al₂O₃(s) + 3 C(s) + 1.97 × 10³ kJ → 4 Al(s) + 3 CO₂(g) ?

How many moles of bromine will react with 0.0500 mole of C₂H₂ in the reaction C₂H₄ + Br₂ → C₂H₄Br₂?

The decomposition of potassium chlorate is written as shown below.What energy change occurs when 12.3 g of KClO₃ decompose? 2 KClO₃(s) + 89.6 kJ → 2 KCl(s) + 3 O₂(g)

A chemist combines hydrochloric acid with a sodium hydroxide solution,transferring 5.75 kJ of heat.Express this in calories.

The reaction C₆H₆ + HNO₃ → C₆H₅NO₂ + H₂O has a 73.5 percent yield under certain conditions.If 12.75 g of C₆H₆ is used,how much C₆H₅NO₂ will be produced?

Calculate the mass of Na₂O that can be produced by the reaction of 4.00 g of sodium and 2.00 g of oxygen in the reaction 4 Na + O₂ → 2 Na₂O.

When C₂H₅Cl(g) is burned in oxygen,chlorine gas is produced in addition to carbon dioxide and water vapor.5145 kJ of heat are released for every four moles of C₂H₅Cl(g) burned.Which of the following correctly represents the thermochemical equation?

Consider the conversion diagram given below. At which point(s) in the diagram is a molar mass needed?

The metabolism of glucose can be represented by the equation C₆H₁₂O₆(s) + 6 O₂(g) → 6 CO₂(g) + 6 H₂O(g) ΔH = -2.82 × 10³ kJ.How many grams of glucose must be metabolized to produce 282 kJ of energy?

How many moles of C₆H₁₂O₆ are formed when 0.250 mole of CO₂ is consumed in the reaction 6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂?

Which of the following defines the percent yield for a reaction?

Aqueous HCl is added to an aqueous solution of NaOH at 25 °C and the result is shown in the figure below. Which of the following correctly characterizes this reaction?

A typical candy bar contains 281 food Calories,which is 281 kcal.How many kilojoules are contained in one such candy bar?

How many moles of oxygen are consumed in the complete combustion of 1.60 moles of benzene,C₆H₆?

Convert 357 J to kcal.

Exam 10: Quantity Relationships in Chemical Reactions

In the complete combustion of C3H8O3,how many moles of carbon dioxide are produced when 23.0 g of C3H8O3 burns?

When 1.00 g of C6H12O6(s) is formed during photosynthesis,15.67 kJ of the sun's energy is converted to chemical energy.What is the thermochemical equation for the photosynthesis of glucose?

1.90 × 103 J of heat,in combination with high pressure,are needed to transform one mole of the graphite form of carbon into the diamond form.How many kilocalories is this?

PCl5 can be produced by the reaction PCl3 + Cl2 → PCl5.What mass of PCl3 must be used to produce 127 g of PCl5 if the percent yield is 84.8%?

How much energy is required to produce 1.00 kg of aluminum by the reaction 2 Al2O3(s) + 3 C(s) + 1.97 × 103 kJ → 4 Al(s) + 3 CO2(g) ?

How many moles of bromine will react with 0.0500 mole of C2H2 in the reaction C2H4 + Br2 → C2H4Br2?

The decomposition of potassium chlorate is written as shown below.What energy change occurs when 12.3 g of KClO3 decompose? 2 KClO3(s) + 89.6 kJ → 2 KCl(s) + 3 O2(g)

A chemist combines hydrochloric acid with a sodium hydroxide solution,transferring 5.75 kJ of heat.Express this in calories.

The reaction C6H6 + HNO3 → C6H5NO2 + H2O has a 73.5 percent yield under certain conditions.If 12.75 g of C6H6 is used,how much C6H5NO2 will be produced?

Calculate the mass of Na2O that can be produced by the reaction of 4.00 g of sodium and 2.00 g of oxygen in the reaction 4 Na + O2 → 2 Na2O.

When C2H5Cl(g) is burned in oxygen,chlorine gas is produced in addition to carbon dioxide and water vapor.5145 kJ of heat are released for every four moles of C2H5Cl(g) burned.Which of the following correctly represents the thermochemical equation?

Consider the conversion diagram given below. At which point(s) in the diagram is a molar mass needed?

The metabolism of glucose can be represented by the equation C6H12O6(s) + 6 O2(g) → 6 CO2(g) + 6 H2O(g) ΔH = -2.82 × 103 kJ.How many grams of glucose must be metabolized to produce 282 kJ of energy?

How many moles of C6H12O6 are formed when 0.250 mole of CO2 is consumed in the reaction 6 CO2 + 6 H2O → C6H12O6 + 6 O2?

Which of the following defines the percent yield for a reaction?

Aqueous HCl is added to an aqueous solution of NaOH at 25 °C and the result is shown in the figure below. Which of the following correctly characterizes this reaction?

A typical candy bar contains 281 food Calories,which is 281 kcal.How many kilojoules are contained in one such candy bar?

How many moles of oxygen are consumed in the complete combustion of 1.60 moles of benzene,C6H6?

Convert 357 J to kcal.

In the complete combustion of C₃H₈O₃,how many moles of carbon dioxide are produced when 23.0 g of C₃H₈O₃ burns?

When 1.00 g of C₆H₁₂O₆(s) is formed during photosynthesis,15.67 kJ of the sun's energy is converted to chemical energy.What is the thermochemical equation for the photosynthesis of glucose?

1.90 × 10³ J of heat,in combination with high pressure,are needed to transform one mole of the graphite form of carbon into the diamond form.How many kilocalories is this?

PCl₅ can be produced by the reaction PCl₃ + Cl₂ → PCl₅.What mass of PCl₃ must be used to produce 127 g of PCl₅ if the percent yield is 84.8%?

How much energy is required to produce 1.00 kg of aluminum by the reaction 2 Al₂O₃(s) + 3 C(s) + 1.97 × 10³ kJ → 4 Al(s) + 3 CO₂(g) ?

How many moles of bromine will react with 0.0500 mole of C₂H₂ in the reaction C₂H₄ + Br₂ → C₂H₄Br₂?

The decomposition of potassium chlorate is written as shown below.What energy change occurs when 12.3 g of KClO₃ decompose? 2 KClO₃(s) + 89.6 kJ → 2 KCl(s) + 3 O₂(g)

The reaction C₆H₆ + HNO₃ → C₆H₅NO₂ + H₂O has a 73.5 percent yield under certain conditions.If 12.75 g of C₆H₆ is used,how much C₆H₅NO₂ will be produced?

Calculate the mass of Na₂O that can be produced by the reaction of 4.00 g of sodium and 2.00 g of oxygen in the reaction 4 Na + O₂ → 2 Na₂O.

When C₂H₅Cl(g) is burned in oxygen,chlorine gas is produced in addition to carbon dioxide and water vapor.5145 kJ of heat are released for every four moles of C₂H₅Cl(g) burned.Which of the following correctly represents the thermochemical equation?

The metabolism of glucose can be represented by the equation C₆H₁₂O₆(s) + 6 O₂(g) → 6 CO₂(g) + 6 H₂O(g) ΔH = -2.82 × 10³ kJ.How many grams of glucose must be metabolized to produce 282 kJ of energy?

How many moles of C₆H₁₂O₆ are formed when 0.250 mole of CO₂ is consumed in the reaction 6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂?

How many moles of oxygen are consumed in the complete combustion of 1.60 moles of benzene,C₆H₆?