Question

The number of electrons present in the valence shell of an atom with an atomic number $38$ is

• A. $2$
• B. $10$
• C. $1$
• D. $8$

Answer 1

The correct option is A

$2$

The explanation for the correct option: (A)

1. The atomic number is $38$ for the element strontium.
2. The electronic configuration of strontium is $\left[\mathrm{Ar}\right]3{\mathrm{d}}^{10}4{\mathrm{s}}^{2}4{\mathrm{p}}^{6}5{\mathrm{s}}^2$.
3. The valence shell is 5s².
4. Therefore the number of valence electrons present is $2$.

Hence, option (A) is correct - The number of electrons present in the valence shell of an atom with atomic number $38$ is $2$.