Question

The outermost electron configuration of an element in this is $2s^{2}2p^6.$

1. Which is the element?
2. Write down the complete subshell electronic configuration.
3. Write any two characteristics of this element.

Answer 1

The electron configuration of an element is given as $2s^{2}2p^6.$ Its 1s is filled. Thus, the atomic number of the element is 2+2+6 = 10. Hence, It is neon. [1 Mark]

2. The complete subshell electronic configuration for this is $1s^2,2s^{2}2p^6.$
[1 Mark]

3. The two characteristics of this element are:

• It has an octet complete. [0.5 Mark]
• It is a non-reactive gas. [0.5 Mark]