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.
Copper can best be purified by
roasting the impure copper in a blast furnace
heating the oxide with coke
electrolyzing a copper (ll) salt solution using the impure copper as the anode
converting the impure copper to a trioxonitrate (V)
washing the impure copper with sodium hydroxide solution
Correct answer is C
No explanation has been provided for this answer.
Which of the following carbohydrates does NOT usually occur in the crystalline form?
Fructose
Glucose
Sucrose
Maltose
Cellulose
Correct answer is E
No explanation has been provided for this answer.
isotopy
isomerism
allotropy
hygroscopy
sublimation
Correct answer is C
No explanation has been provided for this answer.
- 108Kj
-54 kj
-27 kj
+27 kj
+54 kj
Correct answer is A
Given that \(KOH_{(aq)} + HCl_{(aq)} \to KCl_{(aq)} + H_{2}O_{(l)} ; \Delta H = -54 kJ/mol\)
The standard heat of neutralization is the amount of heat evolved when 1 mole of hydrogen ion from an acid reacts with 1 mole of hydroxide ion from the base to form one mole of water, under standard conditions.
\(\therefore 2NaOH_{(aq)} + H_{2}SO_{4(aq)} \to Na_{2}SO_{4(aq)} + 2H_{2}O_{(l)} ; \Delta H = -(2 \times 54 kjmol^{-1})\)
\(\therefore \Delta H = -108 kJmol^{-1}\)
Which of the following gases will bleach moist litmus paper?
CI2
CO2
SO2
HCI2
N2 O
Correct answer is A
No explanation has been provided for this answer.