Incorrect statement regarding the structure of dichromate is

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

It has two kinds of bond lengths

Cr – O – Cr Bond angle is 126⁰

It contains pπ – dπ bonds between Cr & O

Each ‘Cr’ is surrounded by 3 oxygens

answer is D.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

Identify the correct structure of dichromate ion class 12 chemistry CBSE

Explanation:

The dichromate ion, ^2-Cr₂O₇, consists of two chromium atoms and seven oxygen atoms. In its structure, each chromium is surrounded by 4 oxygen atoms, not 3.

The chromium atoms are typically in an octahedral geometry, with four oxygen atoms forming bonds around each chromium atom. Therefore, option d is incorrect.

Correct interpretation of other options:

Option a: Dichromate does indeed have two kinds of bond lengths. One is the Cr–O bond in the Cr–O–Cr linkage, and the other is the Cr=O bond in the terminal oxygen atoms.
Option b: The Cr–O–Cr bond angle is approximately 126°, which is typical for such structures.
Option c: There are indeed pπ–dπ bonds between Cr and O in the dichromate structure, as the chromium atoms can engage in d-orbital participation with the p-orbitals of oxygen.

Thus, the incorrect statement is option d.

Watch 3-min video & get full concept clarity