Question

What type of overlap is involved in the formation of C $-$ H bonds in acetylene molecules?

• A. sp$^{3}$ $-$ s
• B. sp$^{2}$ $-$ s
• C. sp $-$ s
• D. sp $-$ sp

Hint:

Alkanes ($C-H$) $\rightarrow sp^3-s$; Alkenes ($C-H$) $\rightarrow sp^2-s$; Alkynes ($C-H$) $\rightarrow sp-s$.

Answer 1

The Correct Option is C

Step 1: Understanding the Question:
The type of overlap depends on the hybridization of the atoms involved in the bond.
Step 2: Detailed Explanation:
Acetylene (ethyne) has the formula \( H - C \equiv C - H \).
Each carbon atom in acetylene is triple-bonded to another carbon and single-bonded to a hydrogen atom.
- The carbon atoms are \( sp \) hybridized to accommodate the linear geometry.
- The hydrogen atom has its valence electron in a \( 1s \) orbital.
- The \( C-H \) sigma (\( \sigma \)) bond is formed by the axial overlap of one \( sp \) hybrid orbital from carbon and the \( 1s \) orbital of hydrogen.
Thus, the overlap is \( sp - s \).
Step 3: Final Answer:
The overlap involved in \( C-H \) bonds in acetylene is \( sp-s \).