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CHEMISTRY

JAMB 2003 - Question 3

Chemistry 2003 JAMB Past Questions - Question 3: What is the percentage by mass of oxygen in AL2(SO4)3.2HO? [Al = 27, S = 32, H = 1, O = 16]

Choose the most appropriate option for the gap .

What is the percentage by mass of oxygen in AL2(SO4)3.2HO? [Al = 27, S = 32, H = 1, O = 16]

A: 14.29%

B: 25.39%

C: 50.79%

D: 59.25%

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Correct Answer

Explanation

Al2(SO4)3.2H2O = 378Oxygen = 224% By mass of oxygen = 224/378 X 100/1= 59.25%