2006-12-17 01:30:06 · 6 answers · asked by mitch 1 in Science & Mathematics ➔ Chemistry
The atomic radius is the distance from the atomic nucleus to the outermost stable electron orbital in an atom that is at equilibrium.
Positive ions have the same no of protons ,but lesser electrons,
thus destroying the electrical charge balance.
As a result of this the electrons aremore strongly attracted towards the nucleus.
Along with the above factor since the electrons lost, are always from the last shell, an orbit is also lost resulting shrinkage of radius.
The 2 factors mentioned above ensure that positive ions are always smaller in radius than the original atom.
2006-12-17 01:35:57 · answer #1 · answered by Som™ 6 · 0⤊ 0⤋
Since the original atom loses 1 electron, the proton in the nuclei of the atom (positive charged) can grab the electron more tightly, and that makes the radius of positive ions become smaller than the original atom's radius
2006-12-17 02:36:04 · answer #2 · answered by t0bl3rone 2 · 0⤊ 0⤋
A positive ion has the same number of protons as the parent atom. But it also has one less level of electrons. Screening of the outer electrons by inner (complete) levels is reduced. The remaining electrons are much more strongly attracted to the nucleus, and the radius falls dramatically when a positive ion forms.
2006-12-17 01:34:26 · answer #3 · answered by Gervald F 7 · 1⤊ 0⤋
If atom has one electron in outermost shell, then when electron is removed whole the shell is removed. as result formed positive ion is small then original atom.
As you know that in neutral atom, number of proton = number of electron. So, if atom has more than two electrons in outermost shell, when one electron is removed, number of electrons is less then no. of protons.More protons attract less electron, so positive ion shrinks. Thats why, size of positive ion is always less than size of atom.
2006-12-17 01:41:14 · answer #4 · answered by Rauf 1 · 0⤊ 0⤋
The size of the atom is determined by the pull on its electrons by the nucelus
Since in a cation electrons are removed, the nuclear charge per electron incereases resulting in more nuclear pull on each electron
This pulls the electrons inward towards the nucleus and the size of atom decreases
2006-12-17 03:58:07 · answer #5 · answered by Anonymous · 0⤊ 0⤋
'Cause by gaining positive charge they are giving off one ore more electrons, so they are "smaller" or rather lighter.
2006-12-17 01:31:58 · answer #6 · answered by Gerino 2 · 0⤊ 1⤋