Question

Why mgcl2 is linear but sncl2 is angular?

Answer 1

In the case of Magnesium chloride(MgCl2),
      Mg is sp hybridized with a bond angle of 180o and hence is linear.

whereas in the case of Stannous chloride(SnCl2),
      Sn is sp2 hybridized with a bond angle of 120o and hence the molecule is angular.

Answer 2

Hello friend,
Here's your answer:

MgCl2 is linear because
i) Mg has a valency of 2.
ii) So it can form only 2 single bonds with Cl. Hence it is Linear. The structure is (1) in the pic.

SnCl2 is angular becuase
i) Sn has a valency of 4.
ii) So it can form 4 single bonds. But only two Cl's are there. Other is Loan pair. The structure is (2) I pic
iii) Because of Bond pair and Loan Pair replulsion. The structure changes to (3) in pic.

Hope my answer helps you