Question

What happens when magnesium is burnt in airr and the products X and Y are treated with water?
`Mg overset("Air")to underset(P)underset(darr H_(2)O)(X)+ underset(P+Q)underset(darr H_(2)O)(Y)`
A. `X-MgO,Y-Mg(OH)_(2),P-Mg(OH)_(2),Q-N_(2)`
B. `X-MgO,Y-Mg_(3)N_(2),P-Mg(OH)_(2),Q-NH_(3)`
C. `X-MgO, Y-Mg_(3)N_(2),P-Mg(OH)_(2),Q-N_(2)`
D. `X-MgO,Y-MgCO_(3),P-Mg(OH)_(2),Q-CO_(2)`

Answer 1

Correct Answer - B
Magnesium reacts with air to form oxide and nitride. On reaction with water the oxide gives hydroxide and nitride gives hydroxide and ammonia.
`2Mg+O_(2)tounderset((X))(2MgO)`
`3Mg+N_(2) to underset((Y))(Mg_(3)N_(2)`
`MgO+H_(2)O to underset((P))(Mg(OH)_(2)`
`Mg_(3)N_(2)+H_(2)O to underset((P))(3Mg(OH)_(2))+underset((Q))(2NH_(3))`