Question

which of the following classifications describes the element with the electron configuration ar4s²3d¹⁰4p⁵?
○ unstable nonmetal
○ stable metal
○ stable nonmetal
○ unstable metal

Explanation:

Step1: Determine the element

The electron configuration is \([Ar]4s^{2}3d^{10}4p^{5}\). The total number of electrons is \(18 + 2+10 + 5=35\). The element with atomic number \(35\) is bromine (\(Br\)).

Step2: Analyze its properties

Bromine is a halogen. Halogens are non - metals. The outermost shell has \(7\) electrons (\(4s^{2}4p^{5}\)). It tends to gain one electron to achieve a stable octet configuration (\(4s^{2}4p^{6}\)). But in its elemental form (\(Br_{2}\)), it is relatively stable under normal conditions.

Answer:

stable nonmetal