JEE Advanced (Fill in the Blanks): Hydrocarbons | Chapter-wise Tests for JEE Main & Advanced PDF Download

Q.1. ................. is most acidic. (Ethane, Ethene, Ethyne) (1981 - 1 Mark)

Ans. ethyne

Sol. Ethyne, because of the high s character of the – C ≡ H bond in ethyne (sp hybridisation).

Q.2. Acetylene is treated with excess sodium in liquid ammonia.
 The product is reacted with excess methyl iodide. The final product is ............... . (1983 - 1 Mark) 

Ans. 2-butyne

Sol. 2-butyne

Q.3. Th e starting material for the manufacture of polyvin yl chloride is obtained by reacting HCl with  ............... . (1983 - 1 Mark) 

Ans. C₂H₂

Sol. C₂H₂

Q.4. Kolbe electrolysis of potassium succinate gives CO₂ and ........ (1993 - 1 Mark) 

Ans. ethylene

Sol. ethylene

Q.5. Addition of water to acetylenic compounds is catalyzed by.........and............ (1993 - 1 Mark) 

Ans. H₂SO₄, HgSO₄

Sol. H₂SO₄, HgSO₄

Q.6. The bond dissociation energy needed to form the benzyl radical from toluene is........than the formation of the methyl radical from methane. (1994 - 1 Mark) 

Ans. less

Sol. less;

NOTE :
 Stability of free radical 

Benzyl  free radical is more stable than methyl
 free radical because of hyperconjugation (no bond resonance).

Q.7. 1, 3-Butadien e with br omine in molar ratio gen erates predominantly ............... . (1997 - 1 Mark)

Ans. 3, 4-dibromo-1-butene-1 (at low temperature) or 1, 4-dibromo-2-butene (at high temperature)

Sol. 3, 4-dibromo-1-butene (at low temperature) or 1, 4- dibromo2-butene (at high temperature