Question

the electron configuration of phosphorous is $1s^2 2s^2 2p^6 3s^2 3p^3$. what is its noble gas configuration?
he $3s^2 3p^3$
ne $3s^2$
he $2s^2 2p^6 3s^2$
ne $3s^2 3p^3$

Explanation:

To find the noble gas configuration, we identify the noble gas with an electron configuration matching the inner electrons of phosphorus. The electron configuration of Ne (neon) is \(1s^2 2s^2 2p^6\), which matches the first part (\(1s^2 2s^2 2p^6\)) of phosphorus's electron configuration (\(1s^2 2s^2 2p^6 3s^2 3p^3\)). So we replace \(1s^2 2s^2 2p^6\) with \([Ne]\), leaving the outer electrons \(3s^2 3p^3\). Thus the noble gas configuration is \([Ne] 3s^2 3p^3\).

Answer:

D. \([Ne] 3s^2 3p^3\) (assuming the last option is D, as the options are: A. \([He] 3s^2 3p^3\), B. \([Ne] 3s^2\), C. \([He] 2s^2 2p^6 3s^2\), D. \([Ne] 3s^2 3p^3\))