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.
0.1
0.5
2.0
4.0
Correct answer is C
The rate of dimension of a gas inversely proportional to the square root of its molecular mass or its density, which is Graham's Law of diffusion of gas.
R ∝ 1√Mm or R ∝ 1√D
Dx = 0.5gdm-3, Dy = 2gdm-3
R= K√D
R√D = k
R1√D1 = R1√D2
Rx√Dx = Ry√Dy
RxRy = √Dy√Dx
= √2√0.5
= 2.0
The reddish–brown rust on iron roofing sheets consists of
Fe3 + (H2O)6
FeO.H2O
Fe2O3.XH2O
Fe3O4.2H22O
Correct answer is C
Iron [Fe] reacts with H2 in the presence of oxygen to form a rust.
4Fe + 3O2 → 2 Fe2O2
Fe2O3 + H2O → Fe2O3.H2O
The IUPAC nomenclature of the structure above is
3-methybut-3-ene
2-methylbut-1-ene
2-ethylprop-1-ene
2-methylbut-2-ene
Correct answer is B
CH2CH2 - CCH3CH2
Start the numbering from the terminal carbon.
0.300g
0.250g
0.2242g
0.448g
Correct answer is D
M = Molar mass × Quantity of Electricity96500 × no of charge
= MmIT96500n
Copper II Chloride = CuCl2
CuCl2 → Cu2+ + 2Cl2
Mass of compound deposited = Molar mass × Quantity of Electricity96500 × no of charge
Q = IT
I = 0.5A
T = 45 × 60
T = 2700s
Q = 0.5 × 2700
= 1350c
Molarmass = 64gmol-1
no of charge = + 2
Mass = 64×135096500×2
Mass = 0.448g
