CHEM 101

Worksheet: Moles #2

1. How many atoms are in a pure copper penny that weights 2.00 g?

2. How many atoms/molecules are in:

a. 3.50 moles aluminum bromide

b. 46.0 g sodium

c. 68.0 g hydrogen sulfide, H₂S

d. 2.00 g carbon dioxide

e. 2.00 moles boron

3. Calculate the number of moles and grams:

a. 3.01 x 10²³ molecules of NaOH

b. 2.41 x 10²⁴ molecules of water

c. 1.20 x 10²⁴ atoms of potassium

4. Consider methane, CH₄

a. Calculate the molar mass.

b. How many grams would equal 0.500 moles?

c. If you had 64.0 g of the compound, how many grams of hydrogen atoms would you have?

d. How many molecules are in one mole of methane?

e. How many atoms are in one mole of methane?