Stoichiometry

If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction, he or she is calculating the _____.

• theoretical yield

• mole ratio

• actual yield

• percentage yield

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

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

Tags

NGSS.HS-PS1-7

Mole ratios are obtained from the _____.

• balanced chemical equation

• periodic table

• molar mass

What is the mole ratio of H₂O to H₃PO₄ in the following chemical equation?   P₄O₁₀ + 6 H₂O --> 4 H₃PO₄ 

• 6:4
• 4:6
• 1:3
• 3:1

Tags

NGSS.HS-PS1-7

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

2 KClO₃ → 2 KCl + 3 O₂
How many moles of oxygen are produced when 6.7 moles of KClO₃ decompose completely?

• 6.7 mol
• 1.0 mol
• 10.1 mol
• 4.5 mol

Tags

NGSS.HS-PS1-7

2Na + 2H₂O → 2NaOH+ H₂

Assuming H₂O is in excess, how many grams of hydrogen can be produced with 120 g of Na?

• 5.2 g

• 2.6 g

• 690 g

• 45 g

Tags

NGSS.HS-PS1-7

 SiO₂ + 3C → SiC + 2CO
I need to add 8 moles of Carbon to the reaction. How many grams of Carbon should I weigh?

• _{96 g}
• 0.67 g
• 2.67 g
• 48 g

Tags

NGSS.HS-PS1-7

A chemist interested in the efficiency of a chemical reaction would calculate the _____.

• mole ratio

• rate of reaction

• percent yield

• energy released

Tags

NGSS.HS-PS1-6

What is an excess reactant?

• amount you end with

• what you run out of first

• what you have left over

• what you start with

Tags

NGSS.HS-PS1-7