have no effect on the equilibrium position
increase the rate of both the forward and reverse reactions equally
favour the forward reaction
favour the reverse reaction
Correct answer is C
N\(_{2(g)}\) + 3H\(_{2(g)}\) ⇔ 2NH\(_{3(g)}\) In the Haber process, the forward reaction is exothermic and the backward reaction is endothermic. If the temperature is decreased, the yield from the exothermic direction is increased i.e. the forward reaction is increased.
Sieving is a technique used to separate mixtures containing solid particles of
small sizes
large sizes
different sizes
the same size
Correct answer is C
Sieving is a simple and convenient technique of separating particles of different sizes.
If the molecular mass of tetraoxosulphate (VI) acid is 98, calculate its vapour density.
196
49
106
82
Correct answer is B
Molecular mass = Vapour Density x 2
Vapour Density = \(\frac{\text{Molecular Mass}}{2}\)
Where Molecular mass = 98g/mol
Vapour Density = \(\frac{98}{2}\)
Vapour Density = 49g/mol
Which of these alloys contains copper?
solder
steel
permallory
bronze
Correct answer is D
Bronze is an alloy consisting primarily of copper, commonly with about 12% tin and often with the addition of other metals (such as aluminium, manganese, nickel or zinc) and sometimes non-metals or metalloids such as arsenic, phosphorus or silicon.
Calculate the percentage composition of oxygen in calcium trioxocarbonate(IV) [Ca=40, C=12, O=16]
16
48
40
12
Correct answer is B
Calcium trioxocarbonate (IV) = CaCO\(_3\)
Percentage of Oxygen = \(\frac{\text{Molar mass of 3O}}{\text{Molar mass of} CaCO_3}\) × 100%
Percentage of Oxygen = \(\frac{(3 \times 16)}{(40 + 12 + 48)}\) x 100%
Percentage of Oxygen = \(\frac{48}{100}\) x 100%
Percentage of Oxygen = 48%