Topic 6.2 - Limiting Reactant & Percent 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

Use the equation 2 Al + 3 Cl₂ ---> 2 AlCl₃. If 2 moles of aluminum and 2 moles of chlorine gas 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

Tags

NGSS.HS-PS1-6

What is the limiting reactant if 10 moles of NH₃ react with 30.0 moles of NO?

4 NH₃+6 NO --> 5 N₂ + 6 H₂O

• NH₃

• NO

• N₂

• water

When 12 moles of O₂ reacts with 1.1 mole of C₁₀H₈ what is the limiting reactant?  C₁₀H₈ + 12 O₂ --> 10 CO₂ + 4 H₂O

• Oxygen
• C₁₀H₈
• Water
• Carbon Dioxide

Tags

NGSS.HS-PS1-7

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

• 1.16%
• 116%
• 85%
• 76%

Tags

NGSS.HS-PS1-7

P₄ + 6 Cl₂ --> 4 PCl₃

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%

How many grams of FeS are formed from 7.62g of Fe reacted with excess S?

Fe + S --> FeS

• 3.82 g

• 7.62 g

• 12.2 g

• 11.4 g

4 NH₃ + 5 O₂ --> 4 NO + 6 H₂O

How many grams of NO are formed if 6.30g of ammonia (NH₃) react with 1.80g of oxygen gas?

• 0.37 g

• 0.045 g

• 1.35 g

• 11.1 g

You need 2 pieces of bread, 1 tablespoon of peanut butter and 2 tablespoons of starwberry jelly to make a sandwich. If you have 10 pieces of bread, 4 tablespoons of peanut butter and 15 tablespoons of jelly, what is the limiting reactant?

• bread

• strawberry jelly

• peanut butter