# Ionic radii of1. Ti^4+ <  Mn^7+2. ^35Cl^- < ^37Cl^-3.K+ > Cl-4. P3+>P5+plz explain with reason?????

69 Points
13 years ago

Dear Nisha chaudary,

concept of atomic size goes like this

1) say there are same electrons and protons for some atom. if u remove one electron from that the protons are higher than electrons. thatswhy we put  + sign on the element for removing electron. when we removed the electron the protons are more so they attract electrons more strongly. so the atomic size will reduce

2) if we take an electron the electrons increases. for that we put an - (negative sign) on that element. in this case elements are more so and protons are low. less protons attracts less so the atomic size will increase.

3)  in this question u need to calculate the protons and electrons for each atom and then u have to decide which one is bigger.

ex: k+   has 19 protons and 18 electrons   and  cl- has 17 protons and 18 electrons.

u can se that the atomic size is greater when electrons are grater than protons therefore the cl- has greater atomic size that k+

All the best.

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Kaustubh Prakash
22 Points
6 years ago
1. their ionic radius is same as no of electrons =17 and protons=17 in both isotopes. the no of neutrons do not affect ionic radius.
Anjishnu Kumbhakar
13 Points
3 years ago
Go for the Z/e ratio.
As,we all know , Z/e is inversely proportional to ionic radius.
So, for Ti⁴+ , the ratio is 1.22 and for Mn²+ the ratio is1.04.
As 1.22 is greater than 1.04 that's why radius Ti⁴+ is less than Mn²+.

Again for Cl-, the ratio is 0.05, and for Cl the ratio is 1. As 1 is greater than 0.05, that's why Cl- is greater than chlorine.

For K+ and Cl-, they are isoelectronic so there electron number is same but in proton number Cl is less than K. So ionic radii of K+ is less than Cl-.

For P³+ and P5+ , the ionic radii is 1.25 and 1.5 respectively. As 1.253+ is greater than P5+ .