The action of heat on the blue crystalline solid L gives a reddish brown gas M, a gas which relights a glowing splint and leaves a black residue. When as N, which has a rotten egg smell, is passed through a solution of L a black precipitate is formed.
(i) Identify L, M and N (Name or formula).
(ii) Write the equation for the action of heat on L.
(iii) Write the equation for the reaction between the solution of L and the gas N.