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.
15.50 g
7.10 g
3.55 g
1.80 g
Correct answer is C
2 * 35.5g of chlorine has a volume of 22.4 dm3 at s.t.p
∴ xg of chlorine will have a volume of 1.12 dm3
x = (1.12 * 35.5 * 2)/22.4 = 3.55g
2, 1, 2
4, 1, 2
4, 2, 1
1, 2, 1
Correct answer is C
No explanation has been provided for this answer.
The oxidation state of oxygen in tetraoxosulphate (VI) acid is
-4
-2
+4
-8
Correct answer is B
H2SO4
(O.N of hydrogen * 2 ) + O.N of sulphur + O.N of oxygen * 4 = 0
∴ 1 * 2 + 6 + 4x = 0
2 + 6 + 4x = 0
8 + 4x = 0
4x 0 - 8 = -8
4x = -8
x = -8/4 = -2
Calculate the number of moles of HCl present in 20cm3 of a 0.75M solution of the acid
0.015 mole
0.038 mole
3.800 moles
1.500 moles
Correct answer is A
Number of moles = (conc. in mol/dm3*volume in cm3)/1000
(0.75 * 20)/100 = 0.015 mole
Dissolving some pellets of NaOH in water would result in
a decrease in the free energy of the solution
a decrease in the entropy of the solution
a lowering of the temperature of te solution
an increase in the entropy of the solution
Correct answer is D
No explanation has been provided for this answer.