Question

identify the period and group of the element that has the electron configuration ne3s²3p³.
period 3, group 1
period 3, group 15
period 2, group 2
period 3, group 13

Explanation:

• The period number is determined by the highest principal quantum number (\(n\)) in the electron configuration. Here, the highest \(n\) is \(3\) (from \(3s^{2}3p^{3}\)), so the element is in period \(3\).
• For the group number:
• For main - group elements ( \(s\) and \(p\) - block elements), the group number is calculated as \(8 + \text{(number of }s+\text{number of }p\text{ electrons in the valence shell)}\) (when \(n\) is the highest principal quantum number).
• The valence - shell electron configuration is \(3s^{2}3p^{3}\). The number of \(s\) electrons (\(n = 3\)) is \(2\) and the number of \(p\) electrons (\(n = 3\)) is \(3\). So the group number is \(2 + 3+ 10=15\) (another way: in the \(p\) - block, group number \(=10+\text{(number of valence }s + p\text{ electrons)}\), and \(2 + 3=5\), and for \(p\) - block elements starting from group \(13\), group number \(=10 + 5=15\)).

Answer:

period 3, group 15