(i) CuCl is more covalent than NaCl. Give reason. (ii) Draw and explain the molecular orbital diagram of Boron molecule.

(i) CuCl is more covalent than NaCl. Give reason. (ii) Draw and expla

1.	(i) CuCl is more covalent than NaCl. Give reason. (ii) Draw and explain the molecular orbital diagram of Boron molecule.
Answer» Solution :(i) 1. Cations having `ns^(2)np^(6)nd^(10)` configuration show greater polarising power than the cations with `ns^(2)np^(6)` configuration. Hence they show greater covalent character. 2. `CuCl` is more covalent than `NaCl`. As compared to `Na^(+)(1.13Å),Cu^(+)(0.6Å)`is small and has `3S^(2)3p^(6)3d^(10)` configuration. 3. Electronic configuration of `Cu^(+)" :"[Ar]3s^(2)3p^(6)3d^(10)` electronic configuration of `Na^(+)" :" [He]2s^(2)2p^(6)` So `CuCl` is more covalent that `NaCl` (ii) 1. Electronic configuration of `B=1s^(2)2s^(2)2p^(3)` 2. Electronic configuration of `B_(2)=sigma1s^(2)sigma^()1s^(2)SIGMA2S^(2)sigma^()2s^(2)pi2p_(x)^(1)pi2p_(Z)^(1)` 3. Bond order `=(N_(b)-N_(a))/(2)=(6-4)/(2)=1` 4. `B_(2)` MOLECULE has two unpaired electrons hence it is paramagnetic.