Chemistry, Chapter 12, Stoichiometry, Post Assessment

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

Tags

NGSS.HS-PS1-7

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

• 1
• 2
• 3
• 4

The equation for Percent Yield:

• (predicted/experimental) X 100

• (actual or experimental/theoretical or 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

Tags

NGSS.HS-PS1-7

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

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

For the Balanced Reaction: 3 Mg + 1 Fe₂O₃ → 3 MgO + 2 Fe; What is the Ratio of moles of Mg to moles Fe?

• 3mol Mg / 2 mol Fe
• 2 mol Mg/ 3 mol Fe
• 1 mol Fe/ 2 mol Fe
• 3 mol MgO / 2 mol Fe

Tags

NGSS.HS-PS1-7