Answer to Question #350496 in General Chemistry for japhet

Question

Arrange the following iso-electronic species in order of decreasing atomic radius. Na+

Mg2+, Al3+, Si4+, N3-

, 02-

, F, Ne

Answer 1

The order of magnitude of ionic radii of ions Na+,Mg2+,Al3+ and Si4+ is [MP PMT 1996] Na+>Mg2+>Al3+>Si4+. All are isoelectronic but nuclear charge per electron is greatest for Si4+. So it has smallest size and nuclear charge per electron for Na+ is smallest.