1. Calculate the percent compostion of Sodium Sulfate.

2. Na 2 SO 4 = 142.00 g/mol % Na = (45.98/142.00) 100 = 32.3% %S = (32.01/142)100 = 22.5 % % O = 100 - 54.8 = 45.2%

3. A sample of sodium chloride is 25.00 grams. Calculate the mass of sodium in the sample.

4. NaCl = 58.44 g/mol % Na = (22.99/58.44) 100 = 39.3% 25.00 g (.393) = 9.83 g There is 9.83 gram of sodium in the sample.

5. Which has a great mass of potassium? 25.00 g of KCl or 50.00 g of KI?

6. KCl = 74.46 g/mol KI = 165.91 g/mol %K in KCl = (39.01/74.46)100 = 52% %K in KI = (39.01/165.91) 100 = 23%

7. 25.00 g KCl (.52) = 13.0 g K 50.00 g KI (.23) = 11.5 g K There is more grams of K in 25.00 g KCl than in 50.0 g KI