WEEK 8-PERCENT COMPOSITION BY MASS

1. How do you describe percentage composition of a compound?

• A. The mass of each element in a compound compared to the entire mass of the compound multiplied by 50.

• B. The mass of each element in a compound compared to the entire mass of the compound multiplied by 100.

• C. The mass of each element in a compound compared to the entire mass of the compound multiplied by 20.

• D. The mass of each element in a compound compared to the entire mass of the compound multiplied by 80

2. How many percent of Hydrogen (H) is present in water (H20) ? (H- 1; O- 16)

• A. 12%

• B. 11%

• C. 13%

• D. 10%

3. The presence of   in the atmosphere causes acid rain.

How many percent of Sulfur is present in  (Molar Mass = 64.00g/mole)? (S- 32 ; O- 16)

• A. 40.00%

• B. 50.00%

• C. 60.00%

• D. 70.00%

4. Ammonium nitrate is a substance used to produce dinitrogen monoxide,  (Molar Mass = 44.02g/mole), a dental anesthetic.

Determine the mass percent of N in dinitrogen monoxide? (N- 28 ; O- 16)

• A. 36.36%

• B. 63.64%

• C. 35.00%

• D. 63.00%

5. How can you apply knowledge on percentage composition?

• A. In maintaining the quality of food product.

• B. In checking the amount of sugar present in the soft drink.

• C. In identifying the correct amount of substance present in a sample.

• D. All of the above