161.
The following equilibrium in established when hydrogen
chloride is dissolved in acetic acid.
$$HCl + C{H_3}COOH \rightleftharpoons C{l^ - } + C{H_3}COOH_2^ + $$
The set that characterises the conjugate acid-base pairs is
A
$$\left( {HCl,C{H_3}COOH} \right){\text{and}}\left( {C{H_2}COOH_2^ + C{l^ - }} \right)$$
B
$$\left( {HCl,C{H_3}COOH_2^ + } \right){\text{and}}\left( {C{H_3}COOH,C{l^ - }} \right)$$
C
$$\left( {C{H_3}COOH_2^ + ,HCl} \right){\text{and}}\left( {C{l^ - },C{H_3}COOH} \right)$$
D
$$\left( {HCl,C{l^ - }} \right)and\left( {C{H_3}COOH_2^ + ,C{H_3}COOH} \right)$$
Since $$HCl$$ is stronger than $$C{H_3}COOH$$ hence acts as
acid. On the other hand $$C{l^ - }$$ is a stronger base than $$C{H_3}COOH_2^ + $$ and is the conjugate base of $$HCI.$$
$$\eqalign{
& HCl + C{H_3}COOH \rightleftharpoons C{l^ - } + C{H_3}COOH_2^ + \cr
& {\text{aci}}{{\text{d}}_{\text{1}}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\text{bas}}{{\text{e}}_{\text{2}}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\text{bas}}{{\text{e}}_{\text{1}}}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\text{aci}}{{\text{d}}_{\text{2}}} \cr} $$
$$HSO_4^ - $$ accepts a proton to form $${H_2}S{O_4}.$$
Thus $${H_2}S{O_4}$$ is the conjugate acid of $$HSO_4^ - .$$
\[\underset{\text{base}}{\mathop{HSO_{4}^{-}}}\,\xrightarrow{+{{H}^{+}}}\underset{\begin{smallmatrix}
\text{conjugate acid} \\
\text{of}\,HSO_{4}^{-}
\end{smallmatrix}}{\mathop{{{H}_{2}}S{{O}_{4}}}}\,\]
165.
What is the percentage dissociation of $$0.1\,M$$ solution of acetic acid? $$\left( {{K_a} = {{10}^{ - 5}}} \right)$$
166.
What is the $$pH$$ at which $$Mg{\left( {OH} \right)_2}$$ begins to precipitate from a solution containing $$0.1\,M\,M{g^{2 + }}$$ ions? $$\left[ {{K_{sp}}\,\,{\text{for}}\,\,Mg{{\left( {OH} \right)}_2} = 1.0 \times {{10}^{ - 11}}} \right]$$
167.
Consider the following equilibrium $$AgCl \downarrow + 2N{H_3} \rightleftharpoons {\left[ {Ag{{\left( {N{H_3}} \right)}_2}} \right]^ + } + C{l^ - }$$ White precipitate of $$AgCl$$ appears on adding which of the following ?
$$2HN{O_3}\left( {aq} \right) + {\left[ {Ag{{\left( {N{H_3}} \right)}_2}} \right]^ + } + C{l^ - } \to AgCl\left( s \right) \downarrow + 2N{H_4} + 2NO_3^ - $$
When nitric acid is added to amine solution, solution is made acidic and the complex $$ion$$ dissociates and liberate silver ion to recombine with chloride $$ion.$$ This is the conformatory test for silver in group 1.
168.
Which of the following statements is/are incorrect?
(i) Aqueous solution of sugar conducts electricity.
(ii) Conductance of electricity increases with an increase in concentration of common salt in aqueous glucose solution.
(iii) Aqueous solution of acetic acid mainly contains unionized acetic acid molecules and only some $$C{H_3}CO{O^ - }$$ and $${H_3}{O^ + }$$ ions.
Aqueous solution of sugar does not conduct electricity.
169.
Ionisation constant of $$C{H_3}COOH$$ is $$1.7 \times {10^{ - 5}}$$ and concentration of $${H^ + }$$ $$ions$$ is $$3.4 \times {10^{ - 4}}.$$ Then, find out initial concentration of $$C{H_3}COOH$$ molecules.
170.
If $${K_{sp}}$$ of $$Ca{F_2}$$ at $${25^ \circ }C$$ is $$1.7 \times {10^{ - 10}},$$ the combination amongst the following which gives a precipitate of $$Ca{F_2}$$ is