Question

question 50 (1 point) of the following elements, which one has the smallest first ionization energy? a aluminum b boron c carbon d silicon

Explanation:

Ionization energy generally decreases down a group and increases across a period. Aluminum (\(Al\)) and silicon (\(Si\)) are in period 3, boron (\(B\)) and carbon (\(C\)) are in period 2. Since \(Al\) and \(Si\) are in a lower - energy level (higher period number), they have larger atomic radii. Among \(Al\) and \(Si\), \(Al\) has a lower first ionization energy because as we move from left to right in a period, the nuclear charge increases and the electrons are more tightly held. \(Al\) has an electron configuration of \([Ne]3s^{2}3p^{1}\), and removing the \(3p^{1}\) electron is relatively easier compared to \(Si\) which has an electron configuration of \([Ne]3s^{2}3p^{2}\).

Answer:

a. aluminum