Question

Assertion: A standard hydrogen electrode is also called a reversible electrode.
Reason: Standard hydrogen electrodes can act both as anode as well as the cathode in an electrochemical cell.

A. Both Assertion and reason are the correct and reason is the correct explanation for assertion.
B. Both Assertion and reason are the correct and reason is not the correct explanation for assertion
C. Assertion is correct but reason is incorrect.
D. Both assertion and reason are incorrect.

Answer 1

Hint: The standard electrode potential can reduce as well as to oxidise any element. The reduction is the process in which the loss of oxygen and gain of hydrogen takes place at the anode whereas Oxidation is the process in which the loss of hydrogen and gain of oxygen takes place at the cathode.

Complete step by step answer:
- In the given question two statements are given in which we have identified the correct one.
- As we know that standard electrode potential is used for measuring the potential of an electrode under a certain condition.
- Standard electrode potential has the standard conditions such as the temperature of 298 K, the pressure of 1 atm and concentration is 1M.
- There are two types of electrode in the electrochemical cell i.e. cathode and anode.
- The cathode is negatively charged where the reduction process takes place because the energy is supplied to the electrode and accepts electrons.
- That’s why at the cathode, the reduction process will take place in which the gain of hydrogen takes place.
- Whereas at the anode, the oxidation reaction takes place in which the gain of electron and oxygen takes place.
- The assertion is the correct statement that is standard electrode potential is also known as reversible electrode because it can change into cathode from anode and from cathode to anode as well.
- The reason is also a correct statement and also a correct explanation of the assertion because if the reduction potential of the other cell is less then it will act as a cathode.
- Whereas if the reduction of the other cell is high then it will act as an anode.
So, the correct answer is “Option A”.

Note: The ability of any species to get reduced by gaining a pair of the electron is known for its reduction potential. If the value of reduction potential is high then it means the element has more power to get reduced.