Question

Assertion: Metallic characters of the elements increases down group while non-metallic character decreases.

Reason: Down the group electron releasing tendency of the element increases while their electron accepting tendency decreases.

Mark the correct choice

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

Answer 1

The correct option is A

Both assertion and reason are correct and the reason is the correct explanation of assertion.

An explanation for assertion statement:

As we go down the group metallic behaviour increases and across the period from left to right non-metallic character increases.

An explanation for reason statement:

1. As we go down the group, the number of shells increases so the distance from the centre of the nucleus to the outermost shell increases i.e., the atomic size increases. Due to this the Ionization potential decreases (amount of energy required to eject an electron from the outermost shell of a gaseous isolated atom), and hence tendency to release electron increases. This means metallic character increases.
2. But as we move across a period, the number of shells remains the same and there is an increment in the number of protons (as the atomic number is increasing). As a result nuclear pull increases and the tendency to accept electrons increases. This means non-metallic character increases.

Hence, A) Both assertion and reason are true, reason is the correct explanation of assertion.