Question:
A magnesium ribbon is burnt in oxygen to give a white compound ‘X’ accompanied by emission of light. If the burning ribbon is now placed in an
atmosphere of nitrogen, it continues to burn and forms a compound ‘Y’.
(a) Write the chemical formulae of X and Y.
(b) Write a balanced chemical equations when X and Y are dissolved in water.
Solution:
(a) The Compound ‘X’ is magnesium oxide (MgO). The compound ‘Y’ is magnesium nitride (Mg3N2)
(b)
$\mathrm{MgO}(s)+\mathrm{H}_{2} \mathrm{O}(l) \longrightarrow \mathrm{Mg}(\mathrm{OH})_{2}(s)$
(X)
$\mathrm{Mg}_{3} \mathrm{~N}_{2}(s)+6 \mathrm{H}_{2} \mathrm{O}(t) \longrightarrow 3 \mathrm{Mg}(\mathrm{OH})_{2}(s)+2 \mathrm{NH}_{3}(g)$
(Y)