When pure aluminium metal is heated to red hot in the presence of nitrogen gas, the compound formed is

A dense white fume is formed when ammonia gas reacts with

N\(_2\)(g) + 3H\(_2\)(g) ↔ 2NH\(_3\)(g) ΔH = - 90 kJ
In the equation above, the yield of ammonia can be decreased by

The gas that can be dried using concentrated tetraoxosulphate (VI) acid is

NH\(_4\)Cl(s) ⇌ NH\(_3\)(g) + HCl(g)
The reaction above can only attain equilibrium if