BITSAT 2017 Slot 2 Solved Paper

I. Number of electrons in

+

C

H3=6+3−1=8
II. Number of electrons in NH2=7+2+1=10
III. Number of electrons in NH4+=7+4−1=10
IV. Number of electrons in NH3=7+3=10
Since, species with same number of electrons are called isoelectronic species, Hence, IInd, IIIrd and IVth are isoelectronic.