I- EXCEPTIONS- Periodic Classification

Question 1

Size

Who has more size/radius between Mn and Cr?

Answer 1

Cr < Mn

Mn has weak metallic bond strength. Metallic radius ∝ 1/metallic bonding

Question 2

Size

Which of the following sequences is correct for decreasing order of ionic radius?
Se-2
I-
Br-
O-2
F-

Answer 2

I- > Se-2 > Br- > O-2 > F-

1st= highest n 2nd= more -ve charge

I- is in period 5 so first. Out of Se and Br from same period Se wins due to more -ve charge.

Question 3

Size

3. Which of the following sequences is correct for decreasing order of atomic radius of Grp 13.
   B Al Ga In Tl

Answer 3

B < Ga < Al < In < Tl

Al < Ga bcoz of poor shielding effect of 3d subshell

Question 4

Size

4. Which of the following sequences is correct for decreasing order of atomic radius in 3d series of d block?

Answer 4

1. Sc > Ti > Vn > Cr > Mn >
2. Fe ≈ Co ≈ Ni <
3. Cu < Zn

1. Zeff dominating 2. Zeff≈σ 3.σ dominating