Question

When a standard reduction potential of the metal is more negative, its ability to displace hydrogen from acid will

• A. increase
• B. decrease
• C. remain unchanged
• D. depends on the acid

Answer 1

The correct option is A increase

Standard reduction potentials (SRP) of the half cell electrodes are calculated and arranged in a series of increasing order which is known as electrochemical series.
The standard electrode potential of $H^{+}/H_2$ couple is zero.

Here, a negative $E^0$ signifies that it has high tendency to get oxidised and the redox couple is a stronger reducing agent than the $H^{+}/H_2$ couple.

A positive $E^0$ signifies that it has high tendency to get reduced and the redox couple is a stronger oxidising agent than the $H^{+}/H_2$ couple.

Hence, more negative is the standard potential, higher is the probability to oxidise and because of that it has high ability to displace hydrogen from acids.