Question
Wed September 14, 2011 By: Ankita Awari
 

sir can you plz explain if an atom gives electron and the other excepts it.but it is an negetive so the atom which is excepting it do not have repulsion?

Expert Reply
Thu September 15, 2011
This property is known as electron affinity. Electron affinity is the ability of an atom to hold an additional electron. If the atom has more tendency to accept an electron then the energy released will be large and consequently the electron affinity will be high. Electron affinities can be positive or negative. 
Yes! repulsion occurs, But it tends to expand the atom a bit.
Chlorine is 2,8,7; Cl- is 2,8,8. Although the electrons are still all in the 3-level, the extra repulsion produced by the incoming electron causes the atom to expand. There are still only 17 protons, but they are now having to hold 18 electrons.
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