Correct order of 1st ionisationpotential (IP) among following elements Be, B, C, N, O is

Options

A. `B lt Be lt C lt O lt N`
B. `B lt Be lt C lt N lt O`
C. `Be lt B lt C lt N lt O`
D. `Be lt B lt C lt O ltN `

Answer

A

Explanation

An atom has electronic configuration
`1s^(2),2s^(2),2p^(6),3s^(2)3p^(6)3d^(3),4s^(2)`
It is a member of d- block element because the last electron is filled in d -subshell as `3d^(3)` and the following electronic configuration is possible for d-subshell as `(n-d)^(( 1 "to"10))`
`{:(,"Group number",IIIB,IVB,VB,VIB,VIIB),(,,3,4,5,6,7),(,ns^(2)(n-1)s^(2)p^(6),d^(1),d^(2),d^(3),d^(4),d^(5)):}`
`{:(,VIII,VIII,VIII,IB,IIB),(,8,9,10,11,12),(,d^(6),d^(7),d^(8),d^(9),d^(10)):}`

Hence, it is member of third group