Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.
EX3 and EX5
EX3 only
EX5 only
EX2 and EX3
Correct answer is A
No explanation has been provided for this answer.
For iodine crystals to sublime on heating, the molecules must acquire energy that is?
less than the forces odf attraction in the solid
equal to the forces of attraction in th solid
necessary to melt the solid
greater than the forces of attraction in both the solid and the liquid phases
Correct answer is D
No explanation has been provided for this answer.
2.50
3.50
3.75
7.50
Correct answer is C
2KClO3(s) → 2KCl(s) + 3O2(g)
From the above balanced equation, 2 moles of reactant decomposed to give 3 moles of O2 i.e.
i mole of reactant will produce (3)/(2) moles O2.
∴ 2.5 moles KClO3 will give
= 3.75 moles
A balanced chemical equation obeys the law of?
conservation of mass
difinite proportions
multiple proportions
conservation of energy
Correct answer is A
No explanation has been provided for this answer.
Which of the following substances is a mixture?
Sulphur powder
Bronze
Distilled water
Ethanol
Correct answer is B
Bronze is a mixture of copper and tin. Water is a compound of the elements hydrogen and oxygen.