Stoichiometry Review

N₂ +  3H₂ → 2NH₃ 
How many moles of hydrogen are needed to react with 2 moles of nitrogen?

• 6
• 2
• 3
• 1

2H₂   +   O₂  →  2H₂O
How many moles of water can be produced if 8 moles H₂ are used?

• 4 moles
• 8 moles
• 16 moles
• 2 moles

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

• 3mol Mg / 2 mol Fe
• 2 mol Mg/ 3 mol Fe
• 1 mol Fe/ 2 mol Fe
• 3 mol MgO / 2 mol Fe

Cl₂ + 2KBr → Br₂ + 2KCl
How many grams of potassium chloride (KCl) can be produced from 356 g of potassium bromide (KBr)?

• 749 g
• 223 g
• 479 g
• 814 g

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

B₂H₆ + 3O₂ -->2 HBO₂ + 2 H₂O
 What mass of O₂ will be needed to burn 36.1 g of B₂H₆?

• 13.8 g O₂
• 3.86 mol of O₂
• 125.2 g O₂

Balance the following reaction :
 
CaC₂(s)   +   H₂O(l)   -->   C₂H₂(g)   +   Ca(OH)₂(aq)

• 1,2,2,2
• 1,2,1,1
• 2,1,1,1
• 2,1,2,1

The limiting reactant

• slows the reaction down
• is used up first
• is the reactant that is left over
• controls the speed of the reaction

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

When does a chemical reaction stop?

• When the lab is finished
• When the excess reactant is used up
• When the limiting reactant is used up
• Chemical reactions never stop