IIT JAM

follow

Top Resources

S

Shib Sagar posted an Question

July 16, 2020 • 23:21 pm

30 points

IIT JAM
Chemistry (CY)

Atomis size of mg+2 > atomic size of li+ here clash between shall and charge help pz

atomis size of mg+2 > atomic size of Li+ here clash between shall and charge help pz

2 Answer(s)

0 Likes
3 Comments
0 Shares

>
Priyanshu kumar

We have to keep in mind the following points :- 1. As we move down the group the size increases. 2.. As we move move from left to right in a particular period the size decreases. 3.. As the positive charge on an element increases, the size decreases because as more and more electrons goes , the nuclear attraction increases , and the size of the atom decreases .
- Likes(0)
- Reply(1)
keep this points in mind...😊
- Like(0)

>
Dinesh khalmaniya 1 Best Answer

Now, coming to Li+ and Mg2+, the values of their radii are 0.74 A and 0.72 A respectively ('A' stands for angstrom unit). Thus, the lithium ion with +1 charge is only marginally larger than the magnesium ion having a charge of +2.
- Likes(0)
- Reply(6)
We have to keep in mind the following points :- As we move down the group the size increases. As we move move from left to right in a particular period the size decreases. As the positive charge on an element increases, the size decreases because as more and more electrons goes , the nuclear attraction increases , and the size of the atom decreases . So, if we see here Na+ is larger in size than Li+ because Na comes down in the group . Mg2+ is smaller than Na+ because of two reasons . It is located to right of the Na+ atom in the 3rd Period and it also has +2 charge on it. Mg2+ is larger than Be2+ because Mg comes down in the group.
- Like(0)
got it??
- Like(0)
please accept the answer if you got it 🙏🙏🙏🙏
- Like(0)
sir is it an exception because down the grp shall inreases if i consider shall than mg wins and if i consider position charge then Li wins so now what to do
- Like(1)
yes, this is exception case so we will move practical data which say Li+ is larger than Mg+2
- Like(0)
you know every concept is based on data if data not favour then it is exceptional case😊😊
- Like(0)

>
Priyanshu kumar

there is very little difference in size between Mg2+ and li+..Li+ has little bit more size than Mg2+.... Reason- The size difference b/w Li+ and Mg2+ is just of 0.2 A°. Size of Li+ is 0.74A° whereas that of Mg2+ is 0.72A°. That's why lithium and magnesium have diagonal relationship in their chemical properties. Li+ is greater than Mg2+ because of higher charge on nucleus of Magnesium 2+. As Li+ has lost only one electron, whereas Mg2+ lost two electrons, so nucleus Mg2+ tends to pull more electron towards itself. check this👇
- Likes(0)
- Reply(5)
please mark the answer if it helps😊🙏
- Like(0)
got shib??
- Like(0)
if you have any doubt in this then ask and clear your doubt😊🙏
- Like(0)
https://thechemistryguru.com/neet/s-block-elements-lithium-diagonal-relationship-with-magnesium/ check this too for diagonal relationship between Li and Mg..as they have nearly same chemical properties
- Like(0)
any doubt shib??
- Like(0)

T