Question

Assertion :Two successive ionisation energies of Argon are $56.8eV$ and $36.8eV$ respectively. Reason: $Z_{eff}$ of Ar $\left(3s^{2}3p^6\right)$ is greater than $A{r}^{+}\left(3s^{2}3p^5\right).$

Read the above assertion and reason and choose the correct option regarding it.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but 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

The correct option is C Assertion is correct but Reason is incorrect

Two successive ionisation energies of Argon are 56.8 eV and 36.8 eV respectively. A very high energy is required to remoe an electron from stable noble gas core. Hence, the first ionization energy is higher than the second ionization energy.
Zeff of Ar $\left(3s^{2}3p^6\right)$ is smaller than $A{r}^{+}\left(3s^{2}3p^5\right).$
Assertion is correct but Reason is incorrect