Stoichiometry (Limiting & Excess) Bell-Ringer

Which term describes the substance that is completely consumed (used up) during a chemical reaction?

• Excess reactant

• Limiting reactant

• Percent yield

• Theoretical yield

Jesus and Jonathan conducted a chemical reaction. They weighed out 5.43 grams of NaOH after the hydroxide ions all reacted. This is known as the:

• Excess yield

• Limiting yield

• Theoretical yield

• Molar mass

Once you calculate how much each reactant will produce, how do you know which reactant is the limiting reactant?

• The one that produces more product

• The one that starts out with the lowest amount of reactant

• The one that produces the least product

• The one that is left over

If ammonia, NH3, is burned in air, the following reaction takes place:

4 NH3 + 3 O2 → 2 N2 + 6 H2O

Given that you started with 51.0 g of NH3, what mass of water will be produced?

What are you trying to find?

• Moles of A

• Grams of A

• Moles of B

• Grams of B

What is the molar ratio of O2 to CO2?

• 3/5

• 5/3

• 1/5

• 5/4

• 5/1