Engineering Board Exam Reviewer · Chemistry · medium
What is the percentage by mass of oxygen in water? (Use H = 1, C = 12, N = 14, O = 16, Na = 23, S = 32, Cl = 35.5, Ca = 40)
- 33.33%
- 88.89%
- 11.11%
- 50.00%
Answer
B. 88.89%
Solution
%O = 16/18 × 100 = 88.89%.
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