Stoichiometry II Limiting/Excess Review

When you use a balanced chemical equation to calculate the amount of a product on paper it is referred to as the 

• experimental value
• theoretical value
• true amount
• percent yield

If 15 grams of copper (II) chloride react with 20 grams of sodium nitrate, how much sodium chloride can be formed? 

• 13.04 g
• 130.4 moles
• 130.4 g
• 13.04 moles

Theoretical yield = 73g
Actual yield = 62g
Calculate the percent yield.

• 1.16%
• 116%
• 85%
• 76%

What is the measured amount of a product obtained from a chemical reaction?

• mole ratio
• theoretical yield
• percentage yield
• actual yield

The limiting reactant

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

How many grams of ammonia (NH₃) can be produced from the reaction of 28 g of nitrogen gas and 25 grams of hydrogen gas? 

• 43 g
• 34 moles
• 25 grams
• 34 grams

Silver nitrate and sodium phosphate are reacted in equal amounts of 200 g each. How many grams of silver phosphate are produced? 
3AgNO₃  + Na₃(PO₄)  --->  Ag₃(PO₄)  + 3NaNO₃

• 164 g
• 64 g
• 146 g
• 164 moles

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

What is a limiting reactant?

• the reactant that determines how much product can be made
• the reactant that is in excess
• the product that you can make the most of
• the amount of reactants that react with each other

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

• Mg
• H₂
• MgCl₂
• HCl