Question

Which of the following element needs only one electron to attain noble gas configuration?

• A. Sodium
• B. Oxygen
• C. Chlorine
• D. Neon

Answer 1

The correct option is C Chlorine

The table given below shows the electronic configuration of given elements and the number of electrons present in their outermost shell. $$\begin{array}{ccc}\text{Elements}& \text{Electronic configuration}& \text{Electrons in outermost shell}\\ \text{Sodium}& (2,8,1)& \text{1}\\ \text{Oxygen}& (2,6)& \text{6}\\ \text{Chlorine}& (2,8,7)& \text{7}\\ \text{Neon}& (2,8)& \text{8}\end{array}$$
From the table, it is clear that chlorine $\text{(Cl)}$ is the element among the given options whose atom needs only one electron to attain noble gas configuration.