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.
According to charles' law, the volume of a gas becomes zero at
0 oC
-100 oC
-273 oC
-373 oC
Correct answer is C
No explanation has been provided for this answer.
112 cm2
224 cm2
448 cm2
2240 cm2
Correct answer is C
CaCO3(s) + 2HCl(aq) → CaCl2 + H2O(l) + CO2
The relative molecular mass of CaCO3 = 40 + 12 + 16 * 3 = 52 +48 = 100 ;
Relative molecular mass of CO2 = 12 + 10 * 2 = 44
From the above equation, 100g of CaCO3reacts with 44g of CO2 at s.t.p. i.e 22.4 dm3
2g of CaCO3 will react with (2*22.4)/100 of CO2 = 0.448 dm3
0.448 dm3 = 0.448 * 1000 = 448cm3
0.8g
4.0g
40.0g
80.0g
Correct answer is B
Equation of the reaction
H2SO4(g) + CuO(s) → Cu4(aq) + H2O
Relative molecular mass of H2SO4 = 1 + 2 + 32 + 16 + 4 = 98
Relative molecular mass of CuO = 64 + 16 =80
From the above equation, 98s of H2SO4 reacts with 80s of CuO.
∴ 4.9g of H2SO4 will react with
= (4.9 * 80)/98 of CuO = 392/98 = 4.0g
A chemical reaction is always associated with
an increase in the composition of one of the substance
a change in the volume of the reactants
a change in the nature of the reactants
the formation of new substance
Correct answer is D
No explanation has been provided for this answer.
evaporation
distillation
crystallization
sublimation
Correct answer is D
No explanation has been provided for this answer.