Stoichiometry and Chemical Reaction Practice

What is the first thing you must do to solve a stoichiometry problem?

• Write a Balanced Equation
• Panic
• Write an Unbalanced Equation
• Ask for help

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

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

O₂ + CS₂ --> CO₂ + SO₂
What coefficient would go in front of the O₂?

• 1
• 2
• 3
• 4

WO₃ + H₂ --> W + H₂O
What coefficient goes in front of H₂?

• 1
• 2
• 3
• 4

 The equation for Percent Yield:

• (predicted/experimental) X 100
• (experimental/predicted) X 100
• (experimental - predicted)/ Predicted X 100

True or False. You must convert grams to moles to do stoichiometry.

• True
• False

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

2H₂  +   O₂  →  2H₂O
How many moles of oxygen are consumed if 8 moles H₂ are used?

• 2
• 4
• 6
• 8

What is a Limiting Reagent?

• speeds up a reaction
• what you run out of first
• what you have left over
• slows down a reaction

What is a Excess Reagent?

• amount you end with
• what you run out of first
• what you have left over
• what you start with