Question

When a metal is added to dilute $HCl$ solution, there is no evolution of gas. The metal is:

• A. $K$
• B. $Na$
• C. $Ag$
• D. $Zn$

Answer 1

Answer: (C)

$Ag$

We know that the reactivity series has metals in their decreasing order of chemical reactivity.
$K>Na>Ca>Mg>Al>Zn>Fe>Pb>Sn>H>Cu>Hg>Ag>Au$
Metals such as K, Na, that lie above hydrogen in the reactive series, are violent when allowed to react with hydrochloric acid as they reduce hydrogen ions to hydrogen gas, while metals such as copper $\left(Cu\right)$, mercury $\left(Hg\right)$, gold $\left(Au\right)$ and silver $\left(Ag\right)$, that lie below $H$ do not react with hydrochloric acid.