Question

Name two metals that will not displace Hydrogen from dilute acids.

Answer 1

• The reactivity series of metals, also known as the activity series, refers to the arrangement of metals in the descending order of their activities.
• Metals that are placed below hydrogen in the reactivity series cannot displace hydrogen from acids.

Example:

$$\begin{gathered} \mathbf{Cu}\mathbf{}\mathbf{+}\mathbf{}\mathbf{HCl}\mathbf{}\mathbf{\left(}\mathbf{dil}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{\hspace{0.17em}}\mathbf{No}\mathbf{}\mathbf{reaction} \\ \mathbf{Copper} \end{gathered}$$

$$\begin{gathered} \mathbf{Ag}\mathbf{}\mathbf{+}\mathbf{}\mathbf{HCl}\mathbf{}\mathbf{\left(}\mathbf{dil}\mathbf{\right)}\mathbf{}\mathbf{\to }\mathbf{\hspace{0.17em}}\mathbf{No}\mathbf{}\mathbf{reaction} \\ \mathbf{Silver} \end{gathered}$$

• Copper and Silver don't react with dilute Hydrochloric Acid as they are below Hydrogen in the activity series.
• Hence, the two metals which are unable to displace Hydrogen are Copper and Silver.