Limiting Reagent and Percent Yield

1 Cheese + 2 Bread --> 1 Grilled cheese
How many grilled cheeses can you make with 26 slices of bread and 14 pieces of cheese?

• 14
• 13
• 26
• 7

The reactant that is not completely used up in a chemical reaction is called the __________ .

• spectator reagent

• limiting reagent

• excess reagent

• catalyst

1. What is a limiting reagent?

• any reactant used up first in a reaction.
• any reactant left over at the end of a reaction.
• the maximum amount of product formed from a given amount of reactant.
• the purity of the reactant.

When 12 moles of O₂ reacts with 6 moles of C₁₀H₈, what is the limiting reactant?  
1 C₁₀H₈ + 12 O₂ --> 10 CO₂ + 4 H₂O

• Oxygen
• C₁₀H₈
• Water
• Carbon Dioxide

Identify the limiting reagent when 6.00 moles HCl combines with 5.00 moles Mg to form MgCl₂.
 
1 Mg +  2 HCl --> 1 MgCl₂  +  1 H₂   
 

• Mg
• H₂
• MgCl₂
• HCl

A reaction was predicted to produce 32.4 grams of a compound. When the product was measured, there were only 26.1 grams made. What is the percent yield?

• 80.6%
• 6.3%
• 24.1%
• 58.5%

Cl₂ + 2 KBr → Br₂ + 2 KCl

How many grams of potassium chloride can be produced from 356 g of Cl₂ and 356 g of potassium bromide?

• 749 g

• 223 g

• 479 g

• 814 g

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.

P₄ + 6Cl₂ --> 4PCl₃ 
The reaction of 75.0g P₄ with excess chlorine gas produces 110g PCl₃ in lab. Find the theoretical yield and calculate percent yield for the reaction. 

• 78%
• 64%
• 27%
• 33%