Question

For elements B, C, N, Li, Be, O and F, the correct order of first ionization enthalpy is:

• A. \(\text{B<Li<Be<C<O<N<F} \)
• B. \(\text{Li<C<B<O<N<F} \)
• C. \(\text{Li<C<B<O<N<F} \)
• D. \(\text{Li<B<C<O<N<F}\)

Hint:

The first ionization enthalpy increases from left to right in a period due to an increase in nuclear charge and decreases down a group due to the increased size of atoms.

Answer 1

The Correct Option is C

The first ionization energy is the energy required to remove an electron from a neutral atom in its gaseous phase. The general trend for the first ionization energy is that it increases across a period (from left to right) and decreases down a group.
Thus, the order of first ionization enthalpy for the elements provided, starting from the lowest, is: \[ \text{Li}<\text{B}<\text{C}<\text{O}<\text{N}<\text{F} \] Therefore, the correct order is given by option (3).