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Chemistry Past Questions

Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.

123 questions JAMB 2505 WAEC 1623 NECO 168 CUSTOM 10
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Past Questions

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Question 1 of 3 123 total questions
Question 61
jamb 2003
What is the percentage by mass of oxygen in Al2(SO4)3. 2H2O?
[Al = 27, S = 32, H = 1, O = 16]
A14.29%
B25.39%
C50.79%
D59.25%
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Question 62
jamb 2003

Which of the following is physical change?

ABurning kerosene
BFreezing ice cream
CExposing white phosphorus
DDissolving calcium in water
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Question 63
jamb 2003
What volume of oxygen is produced from the decomposition of 2 mole of KCIO3 at s.t.p?
[Molar volume of a gas at s.t.p = 22.4 dm3]
A22.4 dm3
B33.6 dm3
C44.8 dm3
D67.2 dm3
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