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.
0.03 mol dm3
0.12 mol dm3
0.27 mol dm3
0.45 mol dm3
0.90 mol dm3
Correct answer is B
No explanation has been provided for this answer.
When steam is passed over red hot carbon the substances produced are
hydrogen and trioxocarbonate (IV) acid
hydrogen, oxygen and carbon (IV) oxide
hydrogen and carbon (ii) oxide
hydrogen and carbon (IV) oxide
Correct answer is C
Hydrogen and carbon (ii) oxide will be formed when red steam is passed ever red-hot carbon. Option A,B,D are not produced through this process
Calculate the relative molecular mass of Limestone CaCO3, (Ca = 40, C =12, O = 16)
56
100
76
90
Correct answer is B
One molecule of CaCO has 1Ca, 1C and 30 atom relative molecular mass of CaCO3
1 × Ar of Ca +1 × Ar of C +3 × Ar of O
(1 × 40 + 1 × 12 + 3 × 1)
40 + 12 + 48
=100
Option A,C and D will not give 100
In the electrolysis of brine the anode is
platinum
copper
zinc
carbon
Correct answer is D
In the industrial of brine carbon is the anode while mercury is the cathode. Options of A, B, C are not used in brine solution because they are alloy of mercury
The oxidation state of sulphur on H2SO4 acid is
-4
+6
4
-8
Correct answer is B
In SO4. The state of oxygen oxidation number is -2. Options A,C,D do not belong to the oxidation state in SO4