Discuss the possibility of the atom for existing in the following electronic configurations : (i) 1s^(2)2s^(2)2p_(x)^(1) (ii) 1s^(2)2s^(1)2p_(x)^(1)2p_(y)^(1) 2p_(z)^(1) (iii) 1s^(2)2s^(1)2p_(x)^(2) 2p_(y)^(1) (iv) 1s^(2)2s^(2) 3s^(2)

Discuss the possibility of the atom for existing in the following elec

1.	Discuss the possibility of the atom for existing in the following electronic configurations : (i) 1s^(2)2s^(2)2p_(x)^(1) (ii) 1s^(2)2s^(1)2p_(x)^(1)2p_(y)^(1) 2p_(z)^(1) (iii) 1s^(2)2s^(1)2p_(x)^(2) 2p_(y)^(1) (iv) 1s^(2)2s^(2) 3s^(2)
Answer» Solution :(i) This electronic CONFIGURATION is correct since it is in accordance with the rules for filling up of various orbitals. (ii) This electronic configuration is wrong because it violates aufbau principle which states that an orbital with lower energy, i.e., 2s in the present case should be completely filled before the electrons go to HIGHER energy subshell, i.e. 2p in the present case. (iii) This electronic configuration is not correct since it violates HUND's rule. according to this rule, all the three 2p orbitals must have electron each before the PAIRING occurs. But in the present case `2p_(x)` orbital has two electrons while `2p_(Z)` orbital is empty. (iv) This electronic configuration is wrong since after filling 2s-orbital, the electrons should go to 2p-orbital rather than 3s-orbitals.