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.
The oxidation number of iodine in the iodate ion (IO -3) is
-5
-1
+1
+5
Correct answer is D
1O3
[oxidation number of 1] + [oxidation number of 0] x 3 = -1
x + -2 x 3 = 1
x - 6 = - 1
x = - 1 + 6 = +5
Electrolysis is applied in the following processes except
electroplating
extraction of aluminium
extraction of iron
purification of copper
Correct answer is C
No explanation has been provided for this answer.
Increase in temperature
Decrease in temperature
Increase in pressure
Addition of O2 into the mixture
Correct answer is A
The reaction is an exothermic reaction (∆H=-197kjmol).
For continual yield of sulphur(IV)oxide, heat must be liberated.
So,increasing the temperature of the reaction will lead to reduction in yield of \(SO_3\) since it favours backward reaction which is endothermic.
Which of the following compounds absorbs moisture from the atmosphere and dissolves in it?
FeCI3
MgSO4.7H2O
Na2SO 4
KCI
Correct answer is A
No explanation has been provided for this answer.
ZnCl2(aq)
Pb(NO3)2(aq)
CuSO4(aq)
FeSO4(aq)
Correct answer is A
No explanation has been provided for this answer.