The largest ionization enthalpies in any period occur for the

Options

A. alkali metals
B. halogens
C. noble gas elements
D. alkaline earth metals

Answer

C

Explanation

This is consistent with the fact that most noble gases are chemically unreactive because they have such ionization able to the stability of the `1s^(2)` configuration of `He` and the completely filled outer `s-` and `p`-subshell of the other noble gases. In general, shielding is effective when the orbitals in the inner sheels are completely filled. This situation occurs in the case of alkali metals, which have a lone `ns`-outermost electron preceded by a noble gas configuration. Thus, the lowest values in a period are found for the alkali metals. It is a characteristic of reactive metals such as these to lose electrons easily.