Which element belongs to the family of elements, that also includes element gallium?
Which element belongs to the family of elements, that also includes element gallium?
Carbon
Aluminium
Iron
Arsenic
Solution
In the periodic table of elements, gallium (Ga) is grouped in the boron family (group 13) which include the semi-metal boron (B) and the metals aluminium ( $\mathrm{Al}$ ), gallium ( $\mathrm{Ga}$ ), indium (In) and thalium ( $\mathrm{Tl})$.
$
\begin{aligned}
\mathrm{Ga}(Z=31) & =[\mathrm{Ar}] 4 s^2 3 d^{10} 4 p^1 \\
\mathrm{Al}(Z=13) & =[\mathrm{Ne}] 3 s^2 3 p^1
\end{aligned}
$