Question

Which of the following electronic configurations in the outermost shell is characteristic of alkali metals?

• A. $(n-1)s^2{p}^{6}n{s}^2{p}^1$
• B. $(n-1)s^2{p}^6{d}^{10}n{s}^1$
• C. $(n-1)s^2{p}^{6}n{s}^1$
• D. $n{s}^{2}n{p}^6(n-1)d^{10}$

Answer 1

Answer: (C)

$(n-1)s^2{p}^{6}n{s}^1$

The electronic configuration $(n-1)s^2{p}^n{s}^1$ represents alkali metals.
They include $Li$, $Na$, $K$, $Rb$, $Cs$ and $Fr$.
For example, the electronic configuration of $Li$ is $1s^{2}2s^1$ and the electronic configuration of $Na$ is $1s^{2}2s^{2}2p^{6}3s^2$.