A) \[{{H}_{3}}CCH_{2}^{-}>NH_{2}^{-}>HC\equiv {{C}^{-}}>O{{H}^{-}}\]
B) \[HC\equiv {{C}^{-}}>C{{H}_{3}}CH_{2}^{-}>NH_{2}^{-}>O{{H}^{-}}\]
C) \[O{{H}^{-}}>NH_{2}^{-}>C{{H}^{-}}>{{H}_{3}}CCH_{2}^{-}\]
D) \[NH_{2}^{-}>HC\equiv {{C}^{-}}>O{{H}^{-}}>{{H}_{3}}CCH_{2}^{-}\]
Correct Answer: A
Solution :
The conjugate acids of \[\bar{O}H,\bar{N}{{H}_{2}}HC\equiv {{C}^{-}}\]and\[C{{H}_{3}}CH_{2}^{-}\] are \[{{H}_{2}}O,N{{H}_{3}},HC=CH\]and \[C{{H}_{3}}-C{{H}_{3}}\] respectively. Their acidic strength is as \[HOH>HC>N{{H}_{3}}>C{{H}_{3}}C{{H}_{3}}\] A strong acid has a weak conjugate base, hence the decreasing order of basic strength is : \[C{{H}_{3}}CH_{2}^{-}>HC\equiv {{C}^{-}}>O{{H}^{-}}\]You need to login to perform this action.
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