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Question
Assertion (A): Generally, ionisation enthalpy increases from left to right in a period.
Reason (R): When successive electrons are added to the orbitals in the same principal quantum level, the shielding effect of inner core of electrons does not increase very much to compensate for the increased attraction of the electron to the nucleus.
Options
Assertion is correct statement and reason is wrong statement.
Assertion and reason both are correct statements and reason is correct explanation of assertion.
Assertion and reason both are wrong statements.
Assertion is wrong statement and reason is correct statement.
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Solution
Assertion and reason both are correct statements and reason is correct explanation of assertion.
Explanation:
Ionisation enthalpy increases from left to right across the period due to decrease in atomic size. The electrons present within the subshell has almost same effective nuclear charge.
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