2009 - JAMB Chemistry Past Questions and Answers - page 3

The oxidation state of Cr in K₂Cr₂O₇ is

Which of the following metals is purified commercially by electrolysis?

What current will deposit 3.25g of zinc in 2hrs?
[Zn = 65, F = 96500 mol^-]

C_(s) + H₂O_(g) → H_2(g) + CO_2(g)
ΔG for the reaction above at 1300k is -43KJ. At this temperature, the reaction is

Two equal bulbs, one containing ammonia and the other nitrogen are opened mouth - to - mouth to each other at room temperature. The entropy in the mixture of gases is likely to

In the diagram above, which of the curves represents the evolution of oxygen with time in the equation 2KClO_3(s) → 2KCl_(s) + 3O_2(g)?

A catalyst increase the rate of a chemical reaction by providing a path that

CuO_(s) + H_2(g) ↔ Cu_(s) + H₂O_(l)
What is the effect of increasing the pressure on the equilibrium reaction above?

The equilibrium of an endothermic reaction which proceeds with an increase in volume can be shifted in the reverse direction by

The oxidation of ammonia in excess air produces