Assertion: (A) Boron has a smaller first ionsation enthalpy than beryllium. Reason( R) The penetration of 2s electron to the nucleus is more than the 2p electron hence 2p elecrons is more shielded by the inner core of electrons than the 2s electrons.

Assertion: (A) Boron has a smaller first ionsation enthalpy than beryl

1.	Assertion: (A) Boron has a smaller first ionsation enthalpy than beryllium. Reason( R) The penetration of 2s electron to the nucleus is more than the 2p electron hence 2p elecrons is more shielded by the inner core of electrons than the 2s electrons.
Answer» If both Assertion and Reason are CORRECT and Reason is the CORRECT explanation of the Assertion. If both Assertion and Reason are CORRECT but Reason is not the CORRECT explanation of the Assertion. If Assertion is CORRECT but Reason is INCORRECT. If Assertion is INCORRECT but Reason is CORRECT. Answer :C