Worksheet 3 Chem 110 New Book
1. List the atomic masses of the following elements.
Na _______ Cl _______ N _______
O _______ H _______ C _______
2. Calculate the molecular masses or formula masses of the
H2 ______ H2O ______ P4 ______
CH4 ______ C3H8 ______ H2SO4 ______
NaCl ______ CaF2 ______ Na2SO4 ______
3. Give the mass in grams of one mole of each of the following:
a. H2O b. Cu c. CuO d. H2SO4
e. CH4 f. Na g. HNO3 h. CaF2
4. How many O2 molecules comprise (are in) one mole of O2 ?
5. What is the mass in grams of one mole of O2 ?
6. What is the mass in grams of one molecule of O2 ?
(Hint: you need Avogadro's Number!!)
7. Perform the following conversions:
0.025 mole KCl = ____________ g KCl
56 g SO3 = ____________ mole SO3
6.0 mole CO2 = ____________ molecules of CO2
8. A compound of manganese and oxygen has a composition by mass
of 63.2% Mn and 36.8% O. What is the formula of the compound?
9. Lead metal can be obtained from lead oxide (PbO) by reaction
of charcoal at elevated temperature according to the following
2 PbO + C --> 2 Pb + CO2
a. How many moles of lead can be obtained from 1 mole of lead oxide?
b. What mass in grams of lead can be obtained from 1 mole of lead oxide?
c. What mass in grams of PbO is necessary to make 100 g of lead by the above reaction?
d. How many moles of CO2 are produced when 100 g of lead is produced by the above reaction?
10. Sulfuric acid, an important industrial chemical, is made from
sulfur dioxide (SO2) using the following equation:
2 SO2 + 02 --> 2SO3
SO3 + H2O --> H2SO4
a. How many moles of sulfuric acid can be made from 1 mole of sulfur dioxide?
b. How many grams of sulfuric acid can be made from 150 g of sulfur dioxide?