Stoichiometry

KNO₃ --> KNO₂ + O₂
What coefficients are needed to balance the reaction?

• 2, 2, 1
• 2, 3, 2
• 1, 2, 2
• 1, 3, 1

Tags

NGSS.HS-PS1-7

2H₂   +   O₂  →  2H₂O
How many moles of water can be produced if 8 moles H₂ are used?

• 4 moles
• 8 moles
• 16 moles
• 2 moles

Tags

NGSS.HS-PS1-7

2 H₂ + O₂ → 2 H₂O

How many moles of oxygen are consumed if 8 moles H₂ are used?

• 2

• 4

• 6

• 8

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

Tags

NGSS.HS-PS1-7

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

2 Na + 2 H₂O → 2 NaOH + H₂

How many grams of hydrogen are produced if 120 g of Na are available?

• 5.2 g

• 2.6 g

• 690 g

• 45 g

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

2 Fe₂O₃ + C → Fe + 3 CO₂

You add 28 grams of carbon. You find the actual yield to be 181.2 grams of CO₂. What is the percent yield of CO₂? (Hint: calculate theoretical yield of CO₂ first)

• 58.83%

• 308%

• 64.4%

• 15.5%