NEET Organic Chemistry Some Basic Principles and Techniques — Set 16

Question 1

Which carbocation formed from $ \ce{CH3CH2CH(Cl)CH3} $ via heterolytic cleavage is stabilized by hyperconjugation after a possible rearrangement?

Accepted Answer

Cleavage at $ \ce{C-Cl} $ forms $ \ce{CH3CH2CH+CH3} $ (secondary). No rearrangement is needed, but hyperconjugation with adjacent C-H bonds stabilizes it.

Question 2

The stability of which intermediate increases with resonance?

Accepted Answer

Carbocations can be stabilized by resonance (e.g., allylic or benzylic carbocations), delocalizing the positive charge.

Question 3

In the estimation of carbon and hydrogen, 0.18 g of a compound gave 0.528 g of $ \ce{CO2} $ and 0.108 g of $ \ce{H2O} $. What is the percentage of hydrogen?

Accepted Answer

Mass of H = $ \frac{2}{18} \times 0.108 = 0.012 $ g. Percentage = $ \frac{0.012}{0.18} \times 100 = 6.67\% \approx 7\% $.

NEET Chemistry: Organic Chemistry Some Basic Principles and Techniques — Practice Set 16

Q1. Which carbocation formed from \( \ce{CH3CH2CH(Cl)CH3} \) via heterolytic cleavage is stabilized by hyperconjugation after a possible rearrangement?

Q2. The stability of which intermediate increases with resonance?

Q3. In the estimation of carbon and hydrogen, 0.18 g of a compound gave 0.528 g of \( \ce{CO2} \) and 0.108 g of \( \ce{H2O} \). What is the percentage of hydrogen?

Q4. What is the shape of the carbon atom in \( \ce{CH3CHO} \) attached to the methyl group?

Q5. In Lassaigne’s test, the presence of iodine is confirmed by the formation of a precipitate of what color with silver nitrate?

Q6. In the Carius method, 0.2 g of an organic compound gave 0.235 g of \( \ce{AgCl} \). What is the percentage of chlorine?

Q7. How many \( \pi \) bonds are present in \( \ce{CH2=CH-CH=CH2} \)?

Q8. In Kjeldahl’s method, nitrogen is converted to which compound before titration?

Q9. A compound with 8 \( \sigma \) bonds and 1 \( \pi \) bond has the formula \( \ce{C4H8} \). Which carbon has a bond angle closest to 120°?

Q10. Which of the following has the highest s-character in its hybridization?