Analía Bellizzi – Chemistry Classes

Ronald Reagan High School

Percent Composition Practice

Calculate the percent composition the elements or groups indicated in the following compounds: (answers at the bottom)

 

1) OXYGEN in Sulfuric acid  H2SO

2) COPPER in Copper (II) chloride CuCl2

3)  WATER in Calcium Chloride dihydrate CaCl2•2H2O

4) SULFATE IONS in Sodium sulfate Na2SO4

5) ANHYDROUS SALT  (CuSO4) in copper (II) sulfate pentahydrate CuSO4•5H2O

6) CARBON in Hexane C6H14

7) NITRATE IONS  (NO3)in Aluminum nitrate Al(NO3)3

8) AMMONIUM IONS (NH4+)in Ammonium Phosphate (NH4)3PO4

9) CALCIUM in Calcium Phosphate Ca3(PO4)2

10) ALUMINUM in Aluminum silicate Al2(SiO3)3

answers:

 

  1. 65.30%
  2. 47.40%
  3. 24.49%
  4. 67.60%
  5. 64.00%
  6. 83.72%
  7. 87.32%
  8. 36.24%
  9.  38.71%
  10. 19.15%