Question

Which of the following is the correct configuration of sodium:

• A. $(2,8,1)$
• B. $(8,2,1)$
• C. $(2,1,8)$
• D. $(2,8,2)$

Answer 1

The correct option is A

$(2,8,1)$

The correct option is (A).

Explanation of correct Option:

1. The atomic number of sodium $\left(\mathrm{Na}\right)$ is $11$and the number of electrons in sodium is $11$.
2. When we write the electronic configuration sodium, we can pull all $11$electrons in shells around the nucleus of the sodium atom.
3. The maximum number of electrons allowed in the first shell is $2$, in the second shell is $8$, in the third shell is $18$ and so on.
4. Thus, the electronic configuration of sodium is $(2,8,1)$.

Hence, the electronic configuration of sodium$\left(\mathrm{Na}\right)$ is $(2,8,1)$.