Stoichiometry Quiz Review Honors Chemistry

9.1-9.4 Quiz Review

By Katherine Fehrenbach

Molar Mass

Multiple Choice

What is the molar mass of Cl₂?

• 17 g/mol

• 35.5 g/mo;

• 71.0 g/mol

• 89 g/mol

Multiple Choice

Calculate the molar mass of KOH.

• 28 g/mol

• 56 g/mol

• 84 g/mol

• 112 g/mol

Multiple Choice

Calculate the molar mass of Cu₂O.

• 37 g/mol

• 45 g/mol

• 79.5 g/mol

• 143 g/mol

Multiple Choice

Calculate the molar mass for Al(OH)₃

• 78.0 g/mol

• 72 g/mol

• 28 g/mol

• 25 g/mol

Mole-Mole Conversions

Multiple Choice

4NH₃ + 5O₂-->4NO + 6H₂O
What is the total number of moles of H₂O produced when 12 mole of NH₃ is completely consumed?

• 15
• 18
• 20
• 24

Multiple Choice

6CO₂ + 6H₂O --> C₆H₁₂O₆ + 6O₂ 
What is the total number of moles of water needed to make 2.5 moles of C₆H₁₂O₆?

• 2.5
• 6
• 12
• 15

Mass-Mole Conversions

Multiple Choice

CH₄ + 2 O₂ → CO₂ + 2 H₂O
How many moles of carbon dioxide are produced from the combustion of 110 g of CH₄?

• 13.7 mol
• 2.75 mol
• 6.11 mol
• 6.85 mol

Multiple Choice

Using the balanced chemical equation:

Mg + 2 HCl --> MgCl₂ + H₂

How many grams of MgCl₂ is produced if 4.67 moles of HCl react?

• 219 g MgCl₂

• 4.67 g MgCl₂

• 94 g MgCl₂

Mass-Mass Conversions

Multiple Choice

In the reaction $$4Fe + 3O_2 \rightarrow 2Fe_2O_3$$ , if you have 112 grams of $$Fe$$ (molar mass = 55.85 g/mol), how many grams of $$Fe_2O_3$$ (molar mass = 159.69 g/mol) can be produced?

• 159.69 grams

• 319.38 grams

• 223.38 grams

• 447.76 grams

Multiple Choice

For the reaction $$N_2 + 3H_2 \rightarrow 2NH_3$$ , if you start with 28 grams of $$N_2$$ (molar mass = 28.02 g/mol), how many grams of $$NH_3$$ (molar mass = 17.03 g/mol) can be produced?

• 17.03 grams

• 34.06 grams

• 51.09 grams

• 68.12 grams

Limiting Reactants

Multiple Choice

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.

• AlCl3
• Cl2
• Al

Multiple Choice

Fe + S --> FeS
If 7.62g Fe react with 8.67g S, what is the limiting reactant?

• Fe
• S
• FeS
• none 

Percent Yield

Multiple Choice

CH₄  +  2O₂  →  CO₂  +  2H₂O
24 grams of CH₄ was added to the above reaction. Calculate the theoretical yield of CO₂.

• 66 grams
• 132 grams
• 33 grams
• 8.72

Multiple Choice

When reacting Na with Cl₂, we calculated that the theoretical yield should be 13 grams. Our actual yield was 12.5 grams. What is the percent yield?

• 90.4%

• 104%

• 96.15%

• 1.04%

Multiple Choice

2Fe₂O₃ + 3C → 4Fe + 3CO₂

You add 28 grams of carbon. You find the actual yield to be 81.2 grams of CO₂. What is the percent yield of CO₂? (Hint: calculate theoretical yield of CO₂ first)

• 58.83%

• 308%

• 6435%

• 79.14%