Question

When a substance A reacts with H2O, it produces a combustible gas B and solution of C in water. When another substance D reacts with this solution of C, it produces the same gas B on warming. But D can produce the same gas B on reaction with dil. H2SO4 at room temperature. A imparts golden yellow colour to Bunsen flame. A, B, C and D respectively are

• (A) CaC2, C2H2, Ca(OH)2 and Fe
• (B) Ca, H2, Ca (OH)2 and Sn
• (C) K, H2, KOH and Al
• (D) Na, H2, NaOH and Zn

Answer 1

The Correct Option is D

Explanation:
$2\mathrm{Na}+2{\mathrm{H}}_2\mathrm{O}\to {\mathrm{H}}_2+2\mathrm{NaOH}$(A) (B) (C)$\mathrm{Zn}+2\mathrm{NaOH}\stackrel{\mathrm{A}}{⟶}{\mathrm{Na}}_2{\mathrm{ZnO}}_2+{\mathrm{H}}_2$(D)$\mathrm{Zn}+{\mathrm{H}}_2{\mathrm{SO}}_4\to {\mathrm{ZnSO}}_4+{\mathrm{H}}_2$(Impure)