Question

Which amongst the following is incorrect statement?

• A. The bond orders of O₂⁺, O₂, O₂^- and O2^2- are 2.5, 2, 1.5 and 1, respectively.
• B. C₂ molecule has four electrons in its two degenerate 𝜋 molecular orbitals.
• C. H₂⁺ ion has one electron.
• D. O₂⁺ ion is diamagnetic.

Answer 1

The Correct Option is D

The question involves determining the incorrect statement among the given options. To solve this, we will review each statement briefly based on known chemical principles. 

• Statement 1: Bond Orders of O₂⁺, O₂, O₂^-, and O₂^2-

Bond order can be calculated using molecular orbital theory as:

• O₂: Electronic configuration: (σ2s)²(σ*2s)²(σ2p_z)²(π2p_x, π2p_y)⁴(π*2p_x, π*2p_y)²
  Bond order = (10-6)/2 = 2
• O₂⁺: One electron removed from antibonding π* orbital
  Bond order = (10-5)/2 = 2.5
• O₂^-: One electron added to antibonding π* orbital
  Bond order = (10-7)/2 = 1.5
• O₂^2-: Two electrons added to antibonding π* orbital
  Bond order = (10-8)/2 = 1
• Statement 2: C₂ molecule electrons

C₂ has an electronic configuration of (σ2s)²(σ*2s)²(π2p_x, π2p_y)⁴. Hence, it has 4 electrons in π orbitals. This is correct.

• Statement 3: H₂⁺ ion

The H₂⁺ ion has only one electron, as it is formed by removing an electron from H₂. This is correct.

• Statement 4: O₂⁺ ion is diamagnetic

O₂⁺ has an unpaired electron making it paramagnetic, not diamagnetic. Hence, this statement is incorrect.

Therefore, the incorrect statement is: O₂⁺ ion is diamagnetic.