What is the decreasing order of strength of the bases OH-, NH-2, H-C ≡ C- and CH3CH-2

Question

What is the decreasing order of strength of the bases OH-, NH-2, H-C ≡ C- and CH3CH-2 (A) CH3CH-2 > NH2- > H-C ≡ C- > OH- (B) H-C ≡ C- > CH3-CH-2 > NH2- > OH- (C)  OH-> NH2- > H-C ≡ C- > CH3CH-2 (D)  NH2- > H-C ≡ C- > OH- > CH2CH-2

Tardigrade Admin · Accepted Answer

The conjugate acids of the given bases are H2O, NH3, C2H2, CH3CH3. Their acidic strength are in the order H2O > C2H2 > NH3 > CH3CH3. A weak acid has a strong conjugate base.

Q. What is the decreasing order of strength of the bases $O H^{-}, N H_{2}^{-}, H - C \equiv C^{-}$ and $C H_{3} C H_{2}^{-}$

$C H_{3} C H_{2}^{-} > N H_{2}^{-} > H - C \equiv C^{-} > O H^{-}$

$H - C \equiv C^{-} > C H_{3} - C H_{2}^{-} > N H_{2}^{-} > O H^{-}$

$O H^{-} > N H_{2}^{-} > H - C \equiv C^{-} > C H_{3} C H_{2}^{-}$

$N H_{2}^{-} > H - C \equiv C^{-} > O H^{-} > C H_{2} C H_{2}^{-}$

The conjugate acids of the given bases are $H_{2} O, N H_{3}, C_{2} H_{2}, C H_{3} C H_{3}$ . Their acidic strength are in the order $H_{2} O > C_{2} H_{2} > N H_{3} > C H_{3} C H_{3}$ . A weak acid has a strong conjugate base.

Q. What is the decreasing order of strength of the bases OH−,NH2−​,H−C≡C− and CH3​CH2−​

CH3​CH2−​>NH2−​>H−C≡C−>OH−

H−C≡C−>CH3​−CH2−​>NH2−​>OH−

OH−>NH2−​>H−C≡C−>CH3​CH2−​

NH2−​>H−C≡C−>OH−>CH2​CH2−​