Chapter 10 -- The Mole Review
Name _________________________
1. The scale of atomic masses is based on the mass of what element?
2. What is the unit for atomic mass?
3. What is Avogadro’s number? What does it represent? What is the unit?
4. What is the definition of mole?
5. What is the unit for molar mass?
6. What is the molar mass of a gas at STP?
7. What is the empirical formula?
8. What is the molecular formula?
9. Calculate the formula mass of potassium bicarbonate.
9. Find the molar mass of barium hydroxide.
10. Calculate the number of atoms in 0.56 mol of iron.
11. What is the mass of 7.21 x 1021 molecules of silver acetate?
12. A sample of iron oxide has a mass of 3.192 g. On analysis it was found to contain 2.232 g of iron
and 0.96 g of oxygen. Find the percentage composition of this compound.
13. Find the molecular formula of a sugar containing 40% carbon, 6.7 % hydrogen, and 53.3%
oxygen. The molar mass of the sugar is 180g/mol.
14. Outline or describe the procedure you should follow to determine the molecular formula of a
substance if you know the molar mass and percents of the elements in the substance.
15. Outline or draw a diagram showing how to convert grams to molecules, and molecules to grams.
16. The neurotransmitter norepinephrine is 56.8 percent carbon, 6.5 percent hydrogen, 28.5 percent
oxygen, and 8.3 percent nitrogen. Its molar mass is 169 g/mol. Find the molecular formula of this
substance.
36. Acetylene gas is burned in welding torches. It is composed of 92.26 percent carbon and 7.74
percent hydrogen. Its molar mass is 26.02 g/mol. Calculate the empirical and molecular formula
of acetylene.