An aqueous solution of X is added slowly to an aqueous solution of Y as shown in List-I. The variation in conductivity of these reactions is given in List-II. Match List-I with List-II and select the correct answer using the code given below the lists:
`{:(List-I,List-II),((P)(C_(2)H_(5))_(3)N +CH_(3)COOH,(1)"Conductivity decreases adn then increases"),(" X Y",),((Q)KI(0.1M)+AgNO_(3)(0.01M),(2)"Conductivity decreases and then does not change much"),(" X Y",),((R)CH_(3)COOH+KOH,(3)"Conductivity increases and then does not change much"),(" X Y",),((S)NaOH+Hi,(4)"Conductivity does not change much and then increases"),(" X Y",):}`
Codes:

Options

A. `{:(P,Q,R,S),(3,4,2,1):}`
B. `{:(P,Q,R,S),(4,3,2,1):}`
C. `{:(P,Q,R,S),(2,3,4,1):}`
D. `{:(P,Q,R,S),(1,4,3,2):}`

Answer

A

Explanation

(A) For weak base v/s weak acid titration upto equivalenece point conductivity increases because weak electrolyte (W.A.) is converted to strong electrolyte (salt) but after it weak base does not dissociate appreciably
(B) For `KI +AgNO_(3) rarr AgI(ppt.)+KNO_(3)`
upto equivalence point number of ions remain same but after it increases
(C) For weak acid v/s strong base titration upto equivalence point `OH^(-)` ion is replaced by `CH_(3)COO^(-)` so conductivity decreases but after it weak acid does not dissociate appreciably.
(D) For strong base v/s strong acid titration upto equivalence point `H^(+)`ion is replaced by `Na^(+)` so condutivity decrease but after it increases due to increases in number of ions.