Question

When burnt in air the metal 'X' forms only oxide, where as metal 'Y' forms oxide and nitride. X, Y respectively are

• A. Li, Na
• B. Na, Mg
• C. Ca, Mg
• D. Li, Mg

Hint:

Metals like Li form only oxides on combustion, whereas alkali metals like Na form both oxides and nitrides under similar conditions.

Answer 1

The Correct Option is A

Metal 'X' is Lithium (Li), which when burnt in air forms only lithium oxide (Li$_2$O) because it does not form a nitride in air. On the other hand, Metal 'Y' is Sodium (Na), which forms both sodium oxide (Na$_2$O) and sodium nitride (Na$_3$N) when burnt in air.