3. Stoichiometry

Mole Concept — Quiz

Test your understanding of mole concept with 5 practice questions.

Practice Questions

Question 1

An unknown compound sample with mass 0.345 g contains $2.50\times10^{21}$ molecules. What is its molar mass in g/mol?

Question 2

A 1.00 $\mu$g sample of copper (M = 63.55 g/mol) is analyzed. How many copper atoms does it contain?

Question 3

How many oxygen atoms are present in a 2.50 g sample of iron(III) oxide, Fe$_2$O$_3$? (M = 159.69 g/mol)

Question 4

A 5.00 mL droplet of water (density = 1.00 g/mL) is sampled. How many water molecules does this droplet contain? (M = 18.02 g/mol)

Question 5

What is the mass in grams of $3.00\times10^{23}$ molecules of carbon dioxide, CO$_2$? (M = 44.01 g/mol)