Stoichiometry Checkpoint Review

What is the approximate percent composition of potassium in KHCO₃?

• 19%

• 24%

• 39%

• 61%

What is the percent composition of oxygen in Fe₂O₃ (molar mass = 160 g/mol)?

• 16%

• 30%

• 56%

• 70%

How many moles of O₂ contains exactly 3.01 × 10²³ molecules?

• 0.250 mole

• 0.500 mole

• 16.0 moles

• 32.0 moles

Tags

NGSS.HS-PS1-7

What is the approximate total number of atoms in 1.0 mole of lithium?

• 3.0

• 6.9

• 1.0 × 10²³

• 6.0 × 10²³

Tags

NGSS.HS-PS1-7

What is the molar mass of CO₂?

​ (a)   ​ ​ (b)  

• 44
• g/mol
• 18
• 37
• mol
• g
• g/M

What is the mass for one mole of nitrogen gas? (N₂)

(a)   ​ (b)  

• 7 
• g/mol
• 28
• 14
• g
• mol

What is a mole in chemistry terms?

• 
• 
• 
• 

Tags

NGSS.HS-PS1-7

A student burns 1.50 mol C₃H₈ according to the following reaction: C₃H₈ + 5O₂ → 3CO₂ + 4H₂O. How many grams of carbon dioxide are produced?

• 44.0 g

• 66.1 g

• 132.0 g

• 198.0 g

Tags

NGSS.HS-PS1-7

Potassium chlorate decomposed into potassium chloride and oxygen gas.

2KClO₃ → 2 KCl + 3O₂

How many grams of oxygen gas will be given off from 50.0 grams of potassium chlorate?

• 9.84 grams

• 19.58 grams

• 33.3 grams

• 75.0 grams

Tags

NGSS.HS-PS1-7

Which of the following is true of a limiting reagent?

I. It is a reactant

II. It limits the amount of product formed

II. It determines the maximum amount of product formed.

• I only

• II only

• I and II

• I, II, and III

Tags

NGSS.HS-PS1-7