Bellwork 1 Week 9 3rd Nine Weeks

You need 2 pieces of bread, 1 tablespoon of peanut butter and 2 tablespoons of jelly to make a sandwich.  If you have 10 pieces of bread, 4 tablespoons of peanut butter and 20 tablespoons of jelly, what is the limiting reactant?

• bread
• jelly
• peanut butter
• sandwich

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

The limiting reactant . . .

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

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.

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

• spectator reagent
• limiting reagent
• excess reagent
• catalyst

Why is it important to identify the limiting reagent?

• The limiting reagent speeds up the reaction.

• The limiting reagent controls the amount of product formed.

• If there is no limiting reagent, the reaction will not occur.

• No stoichiometry calculations can be done without a limiting reagent.

P₄ + 3O₂ --> P₄O₆ 
What is the limiting reactant is 12 moles of P₄ react with 15 moles of O₂?

• P₄
• O₂
• P₄O₆ 
• none of the above

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
• None

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

4NH₃ + 5O₂ --> 4NO + 6H₂O

How many Liters of NO are formed if 6.30g of ammonia react with 1.80g of oxygen?

• 1.5 L

• 2.02 L

• 1.01 L

• 8.30 L