Question

The electronic configuration of carbon is $1s^{2}2s^{2}2p^{2}$. There are 12 electrons in $C_{2}.$ The correct electronic. Configuration of $C_{2}$molecule is

• A. $(\sigma 1s^{2})(\sigma*1s^{2})(\sigma 2s^{2})(\sigma*2s^{2})(\sigma 2p_{z}^{2})(\pi 2p_{x}^{2})$
• B. $(\sigma 1s^{2})(\sigma*1s^{2})(\sigma 2s^{2})(\sigma*2s^{2})(\pi 2p_{x}^{2} = \pi 2p_{y}^{2})$
• C. $(\sigma 1s^{2})(\sigma*1s^{2})(\sigma 2s^{2})(\sigma*2s^{2})(\sigma 2p_{z}^{2})(\pi 2p_{x}^{1} = \pi 2p_{1y})$
• D. $(\sigma 1s^{2})(\sigma*1s^{2})(\sigma 2s^{2})(\sigma*2s^{2})(\pi 2p_{x}^{2} = \pi 2p_{y}^{1})$

Answer 1

Answer: (B)

$(\sigma 1s^{2})(\sigma*1s^{2})(\sigma 2s^{2})(\sigma*2s^{2})(\pi 2p_{x}^{2} = \pi 2p_{y}^{2})$

Answer 2

: For atoms like nitrogen and below N in atomic number have higher energy for $P_{z}$orbital, hence the configuration for $C_{2}$molecule is

$(\sigma 1s^{2})(\sigma*1s^{2})(\sigma 2s^{2})(\sigma*2s^{2})(\pi 2p_{x}^{2} = \pi 2p_{y}^{2})$.