Question

the electron configuration of element x ends in $s^2p^1$. what is the symbol for the ion most commonly formed by this element?
a $x^{3+}$
b $x^{5-}$
c $x^{2-}$
d $x^+$

Explanation:

Step1: Identify valence electrons

Element X has $s^2p^1$ valence electrons, so total valence electrons = $2+1=3$.

Step2: Determine common ion formation

Elements with 3 valence electrons typically lose all 3 to reach a stable noble gas electron configuration, forming a +3 ion.

Answer:

a. $X^{3+}$