Question

Which of the following molecules represents the order of hybridisation sp² , sp² , sp, sp from left to right atoms ?

• A. HC ≡ C – C ≡ CH
• B. CH₂ = CH – CH = CH₂
• C. CH₂ = CH – C ≡ CH
• D. CH₃ – CH = CH – CH₃

Answer 1

The Correct Option is C

The question is about determining the hybridization states of the atoms in a given molecule. Let's analyze the provided options to determine which molecule has the correct order of hybridization: sp², sp², sp, sp from left to right.

1. Understanding Hybridization:
   • An atom’s hybridization can be determined by counting the number of atoms connected to it (sigma bonds) and the presence of lone pairs. Use the formula: \( \text{Number of hybrid orbitals} = \text{Number of sigma bonds} + \text{Lone pairs} \)
   • sp² hybridization occurs with three hybrid orbitals; typically, it involves double-bonded carbon (C=C).
   • sp hybridization occurs with two hybrid orbitals, typically seen in triple-bonded carbon (C≡C).
2. Option Analysis:
   • Option 1: HC ≡ C – C ≡ CH
     • All carbons here are involved in triple bonds (sp hybridization), so this does not match the given sequence.
   • Option 2: CH₂ = CH – CH = CH₂
     • All carbon atoms here are involved in double bonds (sp² hybridization), so this does not match the order of sp², sp², sp, sp.
   • Option 3: CH₂ = CH – C ≡ CH
     • The molecule consists of:
       1. CH₂ (double-bonded to CH): sp² hybridized carbon.
       2. CH (double-bonded to C): sp² hybridized carbon.
       3. C (triple-bonded to CH): sp hybridized carbon.
       4. CH (triple-bonded): sp hybridized carbon.
     • This option indeed follows the sequence sp², sp², sp, sp.
   • Option 4: CH₃ – CH = CH – CH₃
     • In this molecule, CH₃ groups are attached to sp³ hybridized carbons, whereas the central CH=CH has sp² hybridization, so it does not match the sequence either.

Upon examination, Option 3: CH₂ = CH – C ≡ CH correctly represents the specified order of hybridization: sp², sp², sp, sp.