Question

Identify the pair of metals which can be used to store Hydrochloric acid safely. A) Zinc and Lead B) copper and Zinc C) Iron and Gold D) Copper and Gold​

Answer 1

Answer:

Solution

verified

Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

The reactivity series follows the order:

Zn>Fe>Fb>H>Cu>Hg

Zinc is above hydrogen in reactivity series. Any element that is above hydrogen in reactivity series can displace hydrogen from dilute hydrochloric acid solution.

Zn+2HCl(dil)→ZnCl

2

+H

2

Copper is below hydrogen in reactivity series. Any element that is below hydrogen in reactivity series can not displace hydrogen from dilute hydrochloric acid solution.

Thus, both Assertion and Reason are correct and Reason is the correct explanation for Assertion.

Answer 2

The pair of metals which can be used to store Hydrochloric acid safely are D) Copper and Gold

• In order to determine in which metal Hydrochloric acid can be stored we have to follow the reactivity series.
• Those metals which lie above hydrogen on the reactivity series cannot be used to store HCl because those metals would easily react with hydrogen to form salt.
• Those metals which lie below hydrogen can only be used to store HCl because hydrogen being more reactive won't allow to form salt.
• Hence, D) Copper and Gold being less reactive than Hydrogen can be used.