At 25^{circ}C,the dissociation constants of a | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The given reaction is: $CN^- + CH_3COOH \rightleftharpoons HCN + CH_3COO^-$This reaction can be expressed as the difference between the dissociati

Vedclass · Accepted Answer

$3.0 	imes 10^{4}$

Vedclass · Answer

(A) The given reaction is: $CN^- + CH_3COOH ightleftharpoons HCN + CH_3COO^-$This reaction can be expressed as the difference between the dissociation of $CH_3COOH$ and $HCN$:$CH_3COOH ightleftharpoons CH_3COO^- + H^+$; $K_a(CH_3COOH) = 1.5 	imes 10^{-5}$$HCN ightleftharpoons H^+ + CN^-$; $K_a(HCN) = 4.5 	imes 10^{-10}$To get the target reaction,we add the first equation to the reverse of the second equation:$CH_3COOH + CN^- ightleftharpoons CH_3COO^- + H^+ + H^+ + CN^- ightleftharpoons HCN + CH_3COO^-$The equilibrium constant $K$ for the reaction is given by:$K = \frac{K_a(CH_3COOH)}{K_a(HCN)}$$K = \frac{1.5 	imes 10^{-5}}{4.5 	imes 10^{-10}}$$K = \frac{1.5}{4.5} 	imes 10^{5} = \frac{1}{3} 	imes 10^{5} = 0.333 	imes 10^{5} = 3.33 	imes 10^{4}$Given the options,the closest value is $3.0 	imes 10^{4}$.

At $25^{\circ}C$,the dissociation constants of acetic acid and $HCN$ are $1.5 \times 10^{-5}$ and $4.5 \times 10^{-10}$ respectively. What is the equilibrium constant for the following reaction? $(CN^- + CH_3COOH \rightleftharpoons HCN + CH_3COO^-)$

Similar Questions

The pairs of compounds which cannot exist together in aqueous solution are :
$I. NaH_2PO_4$ and $Na_2CO_3$ $II. Na_2CO_3$ and $NaHCO_3$
$III. NaOH$ and $NaH_2PO_4$ $IV. NaHCO_3$ and $NaOH$

For a weak electrolyte $A_xB_y$,the degree of dissociation $\alpha$ in terms of concentration $c$ is given by:

One mole of ammonia was completely absorbed in one litre solution each of $(a)$ $1 \ M \ HCl$,$(b)$ $1 \ M \ CH_{3}COOH$,and $(c)$ $1 \ M \ H_{2}SO_{4}$ at $298 \ K$. The decreasing order for the $pH$ of the resulting solutions is (Given $pK_{b}(NH_{3}) = 4.74$)

In which of the following cases,$pH$ is greater than $7$?

Which of the following plots represents the graph of $pH$ against the volume of alkali added in the titration of $NaOH$ and $HCl$?

Vedclass Test Series

Exam Paper Generator

Online Exam Module