Question

Given below are two statements:

Statement (I): The first ionization energy of Pb is greater than that of Sn.
Statement (II): The first ionization energy of Ge is greater than that of Si.

In light of the above statements, choose the correct answer from the options given below:

• A. Statement I is true but Statement II is false
• B. Both Statement I and Statement II are false
• C. Statement I is false but Statement II is true
• D. Both Statement I and Statement II are true

Hint:

Ionisation energy generally decreases down a group due to increasing atomic size and distance of electrons from the nucleus.

Answer 1

The Correct Option is C

- Statement (I) is false: The ionisation energy of Pb is lower than that of Sn because Pb is lower in the periodic table and has a higher atomic size.
- Statement (II) is true: Ge has a higher ionisation energy than Si because it is in the same group but higher in the periodic table, so its electrons are closer to the nucleus.
Final Answer: Statement I is false but Statement II is true.