JEE Main · 2022 · 27 Jul 2022 · Shift 1 · d and f Block Elements

Given below are two statements:

Statement I: Iron (III) catalyst, acidified

K X_{2} Cr X_{2} O X_{7}

and neutral

KMnO X_{4}

have the ability to oxidise

I X^{-}

I X_{2}

independently.
Statement II: Manganate ion is paramagnetic in nature and involves

p π - p π

bonding.
In the light of the above statements, choose the correct answer from the options.

Answer: (B)

Solution

Statement I is false: While

Fe X^{3 +}

and acidified

K X_{2} Cr X_{2} O X_{7}

can oxidize

I X^{-}

I X_{2}

, neutral

KMnO X_{4}

oxidizes

I X^{-}

IO X_{3} X^{-}

(iodate), not to

I X_{2}

.

Statement II is false: The manganate ion

MnO X_{4} X^{2 -}

has one unpaired electron (paramagnetic is correct), but the bonding involves **

d π - p π

** bonding between the metal d-orbitals and oxygen p-orbitals, not

p π - p π

.

Both statements are false. The answer is (B).

JEE Main · 2022 · 27 Jul 2022 · Shift 1 · Single correct option