In the given structure, number of sp and sp^2$sp^{2}$ hybridized carbon atoms present respectively are :

### Core Logic To determine carbon atom hybridization within skeletal networks, evaluate the count of steric components (sigma$\sigma$-bonds attached to each carbon): * 4 text sigmatext-bonds ightarrow sp^3$4 \text{ } \sigma\text{-bonds} ightarrow sp^3$ * 3 text sigmatext-bonds ightarrow sp^2$3 \text{ } \sigma\text{-bonds} ightarrow sp^2$ (typically carbons forming one double bond like mathrmC=O$\mathrm{C=O}$ or mathrmC=C$\mathrm{C=C}$) * 2 text sigmatext-bonds ightarrow sp$2 \text{ } \sigma\text{-bonds} ightarrow sp$ (typically carbons forming a triple bond like -mathrmCequiv C-$-\mathrm{C\equiv C}-$ or -mathrmCequiv N$-\mathrm{C\equiv N}$) ### Step 1: Specific Atom Assignment Let's perform an audit across the skeletal sequence:

* sp^2$sp^2$ Carbons: 1. Carbonyl carbon (mathrmC=O$\mathrm{C=O}$) 2. Carbons sharing the first alkene motif (2 atoms) 3. Carbons sharing the second alkene motif (2 atoms) Total sp^2$sp^2$ carbons = 1 + 2 + 2 = 5$1 + 2 + 2 = 5$ * sp$sp$ Carbons: 1. Carbons bound in the central alkyne group (-mathrmCequiv C-$-\mathrm{C\equiv C}-$) (2 atoms) 2. Terminal nitrile carbon (-mathrmCequiv N$-\mathrm{C\equiv N}$) (1 atom) Total sp$sp$ carbons = 2 + 1 = 3$2 + 1 = 3$ ### Pattern Recognition Count all carbons involved in triple bonds (alkynes, nitriles) to find sp$sp$ items. Count all double-bonded carbons (alkenes, ketones) to quickly isolate the sp^2$sp^2$ population. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Chemistry: Organic Chemistry - Some Basic Principles and Techniques