Question

Consider the elements Ne, Na, Mg. The element with highest first ionization enthalpy and element with lowest second ionization enthalpy respectively are

• A. Na, Ne
• B. Ne, Mg
• C. Na, Na
• D. Mg, Na

Hint:

First ionization enthalpy is higher for elements with stable electron configurations, and the second ionization enthalpy is lower for elements with stable ions after the first ionization.

Answer 1

The Correct Option is B

The ionization enthalpy is the energy required to remove an electron from an atom. The first ionization enthalpy is typically highest for elements with stable electron configurations, while the second ionization enthalpy is influenced by the stability of the resulting ion. 1. **First Ionization Enthalpy:** - Neon (Ne) has the highest first ionization enthalpy because it has a stable noble gas configuration (\( 1s^2 2s^2 2p^6 \)). 2. **Second Ionization Enthalpy:** - Magnesium (Mg) has the lowest second ionization enthalpy because after the first ionization, the \( \text{Mg}^+ \) ion has a stable noble gas configuration similar to neon, making it easier to remove a second electron. Thus, the correct answer is \( \boxed{\text{Ne, Mg}} \).