Practice Mole in Chemistry
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
The fundamental counting unit in chemistry, defined as exactly 6.022 \times 10^{23} particles (atoms, molecules, ions, or other entities).
A 'chemist's dozen'—a huge number that makes atom-counting practical.
Example 1
easyWhat is a mole and why is it useful in chemistry?
Example 2
mediumHow many moles of water are in 36.0 g of \text{H}_2\text{O}? (Molar mass of \text{H}_2\text{O} = 18.0\,\text{g/mol})
Example 3
easyHow many moles are in 40.0 g of NaOH? (Molar mass = 40.0\,\text{g/mol})
Example 4
easyA sample contains 1.204 \times 10^{24} molecules of ammonia. How many moles of \text{NH}_3 is this?