Describlethe theoryassociated with theradiusof anatom as it (a)gainsan electron( b)loses an electron.

Describlethe theoryassociated with theradiusof anatom as it (a)gainsan

1.	Describlethe theoryassociated with theradiusof anatom as it (a)gainsan electron( b)loses an electron.
Answer» Solution :(a) Gain of electron. Whena neutralatomgainsoneelectronto forman anion its radiusincreaeses.Thereason beingthat THENUMBEROF electronsin the anionincreaseswhileits nuclearchargeremainsthe sameas theparentatom.Sincethesamenuclear chargenowattractsgreaternumberof electrons thereforeforce of ATTRACTION of thenucleus on THEELECTRONS of theshellsdecreases(i.e.,effective nuclearchargedecreases) and hencethe electron cloudexpands.In otherwordsthe distancebetweenthe centre of thenucleusand the last shellthatcontainselectronsincreasesthereby INCREASING theionicradius. Thus ( b)Loss of electrons. When a neutralatomloses one electron toforma cationitsatomicradiusdecreases. The reasonbeingthat thenumberof electrons in thecationdecreases while itsnuclear chargeremainsthe sameas the parentatom. Sincethe samenuclearchargenowattractslessernumberof electronsthereforethe FORCE ofattractionof thenucleus ofelectronsof all theshells- increases (i.e.,effectivenuclear chargesincreases ) and hencethe sizeof cationdecreases.Thus