# Solved papers for NEET Chemistry Equilibrium / साम्यावस्था NEET PYQ-Ionic Equilibrium

### done NEET PYQ-Ionic Equilibrium Total Questions - 44

• question_answer1)  The concentration of $[{{H}^{+}}]$ and concentration of $[O{{H}^{-}}]$ of a 0.1 M aqueous solution of 2% ionised weak monobasic acid is: [ionic product of water$=1\times {{10}^{-14}}$]                                                [AIPMT 1999]

A)
$0.02\times {{10}^{-3}}\,M$ and $5\times {{10}^{-11}}\,M$

B)
$1\times {{10}^{-3}}\,M$ and $3\times {{10}^{-11}}\,M$

C)
$2\times {{10}^{-3}}\,M$ and $5\times {{10}^{-12}}\,M$

D)
$3\times {{10}^{-2}}\,M$ and $4\times {{10}^{-13}}\,M$

• question_answer2) The solubility of a saturated solution of calcium fluoride is $2\times {{10}^{-4}}\,mol/L$. Its solubility product is:                                                                                                                                                      [AIPMT 1999]

A)
$12\times {{10}^{-2}}$

B)
$14\times {{10}^{-4}}$

C)
$22\times {{10}^{-11}}$

D)
$32\times {{10}^{-12}}$

• question_answer3)  Which of the following statements about pH and ${{H}^{+}}$ ion concentration is incorrect?           [AIPMT 2000]

A)
Addition of one drop of concentrated HCl in $N{{H}_{4}}OH$ solution decreases pH of the solution

B)
A solution of the mixture of one equivalent of each of $C{{H}_{3}}COOH$ and NaOH has a pH of 7

C)
pH of pure neutral water is not zero

D)
A cold and cone. ${{H}_{2}}S{{O}_{4}}$ has lower ${{H}^{+}}$ ion concentration than a dilute solution of ${{H}_{2}}S{{O}_{4}}$

• question_answer4) Which one of the following is true for any diprotic acid, ${{H}_{2}}X$?                             [AIPMT 2000]

A)
${{K}_{{{a}_{2}}}}={{K}_{{{a}_{1}}}}$

B)
${{K}_{{{a}_{2}}}}>{{K}_{{{a}_{1}}}}$

C)
${{K}_{{{a}_{2}}}}<{{K}_{{{a}_{1}}}}$

D)
${{K}_{{{a}_{2}}}}=\frac{1}{K{{a}_{1}}}$

• question_answer5) 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:     [AIPMT 2001]

A)
$3.4\times {{10}^{-4}}$

B)
$3.4\times {{10}^{3}}$

C)
$6.8\times {{10}^{-4}}$

D)
$6.8\times {{10}^{-3}}$

• question_answer6) Solubility of a ${{M}_{2}}S$ salt is $3.5\times {{10}^{-6}},$ then find out solubility product:          [AIPMT 2001]

A)
$1.7\times {{10}^{-6}}$

B)
$1.7\times {{10}^{-16}}$

C)
$1.7\times {{10}^{-18}}$

D)
$1.7\times {{10}^{-12}}$

• question_answer7) Solubility of $M{{X}_{2}}$-type electrolytes is $0.5\times {{10}^{-4}}mol/L$. Then find out if ${{K}_{sp}}$ of electrolytes:                                                                                                                  [AIPMT 2002]

A)
$5\times {{10}^{-12}}$

B)
$25\times {{10}^{-10}}$

C)
$1\times {{10}^{-13}}$

D)
$5\times {{10}^{-13}}$

• question_answer8)  Which has highest pH?                                                                                                    [AIPMT 2002]

A)
$C{{H}_{3}}COOK$

B)
$N{{a}_{2}}C{{O}_{3~~}}$

C)
$N{{H}_{4}}Cl$

D)
$NaN{{O}_{3}}$

• question_answer9) Solution of 0.1 N $N{{H}_{4}}OH$ and 0.1 N $N{{H}_{4}}Cl$ has pH 9.25, then find out $p{{K}_{b}}$ of $N{{H}_{4}}OH$.                                                                                                       [AIPMT 2002]

A)
9.25

B)
4.75

C)
3.75

D)
8.25

• question_answer10) The solubility product of $Agl$ at $25{}^\circ C$ is$1.0\times {{10}^{-16}}mo{{l}^{2}}{{L}^{-2}}$. The solubility of $Agl$ in ${{10}^{-4}}N$ solution of $KI$ at $25{}^\circ C$ is approximately (in $mol\text{ }{{L}^{-1}}$):                                                                                                                                                [AIPMT 2003]

A)
$1.0\times {{10}^{-10}}$

B)
$1.0\times {{10}^{-8}}$

C)
$1.0\times {{10}^{-16}}$

D)
$1.0\times {{10}^{-12}}$

• question_answer11) The solubility product of a sparingly soluble salt$A{{X}_{2}}$ is  $3.2\times {{10}^{-11}}$. Its solubility (in mol/L) is: [AIPMT (S) 2004]

A)
$\text{5}.\text{6}\times {{10}^{-\text{6}}}$

B)
$\text{3}.\text{1}\times {{10}^{-\text{4}}}$

C)
$\text{2}\times {{10}^{-\text{4}}}$

D)
$\text{4}\times {{10}^{-\text{4}}}$

• question_answer12) At ${{25}^{o}}C,$ the dissociation constant of a base, BOH, is $1.0\times {{10}^{-12}}$. The concentration of hydroxyl ions in 0.01 M aqueous solution of the base would be:                                                         [AIPMT (S) 2005]

A)
$2.0\times {{10}^{-6}}\,mol\,{{L}^{-1}}$

B)
$1.0\times {{10}^{-5}}\,mol\,{{L}^{-1}}$

C)
$1.0\times {{10}^{-6}}\,mol\,{{L}^{-1}}$

D)
$1.0\times {{10}^{-7}}\,mol\,{{L}^{-1}}$

• question_answer13) What is the correct relationship between the pHs of isomolar solutions of sodium oxide $(p{{H}_{1}}),$ sodium sulphide $(p{{H}_{2}})$ sodium selenide $(p{{H}_{3}})$ and sodium telluride $(p{{H}_{4}})$?    [AIPMT (S) 2005]

A)
$p{{H}_{1}}>p{{H}_{2}}>~p{{H}_{3}}>p{{H}_{4}}$

B)
$p{{H}_{1}}<p{{H}_{2}}<p{{H}_{3}}<p{{H}_{4}}$

C)
$p{{H}_{1}}<p{{H}_{2}}<p{{H}_{3}}<~p{{H}_{4}}$

D)
$p{{H}_{1}}>p{{H}_{2}}>p{{H}_{3}}>p{{H}_{4}}$

• question_answer14) ${{H}_{2}}S$ gas when passed through a solution of cations containing HCl precipitates the cations of second group of qualitative analysis but not those belonging to the fourth group. It is because:             [AIPMT (S) 2005]

A)
presence of HCl decreases the sulphide ion concentration

B)
presence of HCl increases the sulphide ion concentration

C)
solubility product of group II sulphides is more than that of group IV sulphides

D)
sulphides of group IV cations are unstable in HCl

• question_answer15) Which of the following pairs constitutes a buffer?                                                                 [AIPMT (S) 2006]

A)
$HN{{O}_{2}}$ and $NaN{{O}_{2}}$

B)
$NaOH$ and $NaCl$

C)
$HN{{O}_{3}}$ and $N{{H}_{4}}N{{O}_{3}}$

D)
$HCl$ and $KCl$

• question_answer16) The hydrogen ion concentration of a ${{10}^{-8}}M\text{ }HCl$ aqueous solution at $298\text{ }K\text{ (}{{K}_{w}}={{10}^{-14}})$ is:                                                                                 [AIPMT (S) 2006]

A)
$1.0\times {{10}^{-6}}M$

B)
$1.0525\times {{10}^{-7}}M$

C)
$9.525\times {{10}^{-8}}M$

D)
$1.0\times {{10}^{-8}}M$

• question_answer17) Calculate the $pOH$ of a solution at $25{}^\circ C$ that contains $1\times {{10}^{-10}}\,M$ of hydronium ions.                                                                                                                                       [AIPMT (S) 2007]

A)
7.00

B)
4.00

C)
9.00

D)
1.00

• question_answer18) A weak acid, $\Delta H,$ has a ${{K}_{a}}$ of $1.00\times {{10}^{-5}}$. If 0.100 mole of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to:                                        [AIPMT (S) 2007]

A)
99.0%

B)
1.00%

C)
99.9%

D)
0.100%

• question_answer19) Equal volumes of three acid solutions of pH 3, 4 and 5 are mixed in a vessel. What will be the ${{H}^{+}}$ ion concentration in the mixture?                                                                           [AIPMT (S) 2008]

A)
$1.11\times {{10}^{-4}}M$

B)
$3.7\times {{10}^{-4}}M$

C)
$3.7\times {{10}^{-3}}M$

D)
$1.11\times {{10}^{-3}}M$

• question_answer20) If the concentration of $O{{H}^{-}}$ ions in the reaction $Fe{{(OH)}_{3}}(s)F{{e}^{3+}}(aq)+3O{{H}^{-}}(aq)$ is decreased by $\frac{1}{4}$ times, then equilibrium concentration of $F{{e}^{3+}}$ will increase by                                                                                                                                                              [AIPMT (S) 2008]

A)
8 times

B)
16 times

C)
64 times

D)
4 times

• question_answer21) Equimolar solutions of the following were prepared in water separately. Which one of the solutions will record the highest pH?                                                                                                                                    [AIPMT (S) 2008]

A)
$SrC{{l}_{2}}$

B)
$BaC{{l}_{2}}$

C)
$MgC{{l}_{2}}$

D)
$CaC{{l}_{2}}$

• question_answer22) The ionisation constant of ammonium hydroxide is $1.77\times {{10}^{-5}}$ at 298 K. Hydrolysis constant of ammonium chloride is                                                                                                                        [AIPMT (S) 2009]

A)
$5.65\times {{10}^{-10}}$

B)
$6.50\times {{10}^{-12}}$

C)
$5.65\times {{10}^{-13}}$

D)
$5.65\times {{10}^{-12}}$

• question_answer23) . What is the $[O{{H}^{-}}]$ in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M $Ba{{(OH)}_{2}}$?                                                                                                      [AIPMT (S) 2009]

A)
0.10 M

B)
0.40 M

C)
0.0050 M

D)
0.12 M

• question_answer24) The dissociation constants for acetic acid and HCN at ${{25}^{o}}C$ are $1.5\times {{10}^{-5}}$ and $4.5\times {{10}^{-10}},$ respectively. The equilibrium constant for the equilibrium,  $HCN+C{{H}_{3}}CO{{O}^{-}}$ would be                                                    [AIPMT (S) 2009]

A)
$3.0\times {{10}^{5}}$

B)
$3.0\times {{10}^{-5}}$

C)
$3.0\times {{10}^{-4}}$

D)
$3.0\times {{10}^{4}}$

• question_answer25) If pH of a saturated solution of $Ba{{(OH)}_{2}}$ is 12, the value of its ${{K}_{sp}}$is               [AIPMT (S) 2010]

A)
$4.00\times {{10}^{-6}}{{M}^{3}}$

B)
$4.00\times {{10}^{-7}}{{M}^{3}}$

C)
$5.00\times {{10}^{-6}}{{M}^{3}}$

D)
$5.00\times {{10}^{-7}}{{M}^{3}}$

• question_answer26) What is $[{{H}^{+}}]$ in mol/L of a solution that is 0.20 M in $C{{H}_{3}}COONa$ and 0.10 M in $C{{H}_{3}}COOH$? (${{K}_{a}}$for $C{{H}_{3}}COOH=1.8\times {{10}^{-5}}$)     [AIPMT (S) 2010]

A)
$3.5\times {{10}^{-4}}$

B)
$1.1\times {{10}^{-5}}$

C)
$1.8\times {{10}^{-5}}$

D)
$9.2\times {{10}^{-6}}$

• question_answer27) 25.3 g of sodium carbonate, $N{{a}_{2}}C{{O}_{3}}$ is dissolved in enough water to make 250 mL of solution. If sodium carbonate dissociates completely, molar concentration of sodium ion, $N{{a}^{+}}$ and carbonate ion, $CO_{3}^{2-}$ are respectively     (Molar     mass     of$N{{a}_{2}}C{{O}_{3}}=106\,g\,\,mo{{l}^{-1}}$)           [AIPMT (S) 2010]

A)
0.955 M and 1.910 M

B)
1.910 M and 0.955 M

C)
1.90 M and 1.910 M

D)
0.477 M and 0.477 M

• question_answer28) In a buffer solution containing equal concentration of ${{B}^{+}}$ and HB, the ${{K}_{b}}$ for ${{B}^{-}}$ is ${{10}^{-10}}$. The pH of buffer solution is                                                                  [AIPMT (S) 2010]

A)
10

B)
7

C)
6

D)
4

• question_answer29)                     A buffer solution is prepared in which the concentration of $N{{H}_{3}}$ is 0.30 M and the concentration of $NH_{4}^{+}$ is 0.20 M. If the equilibrium constant, ${{K}_{b}}$ for $N{{H}_{3}}$ equals $1.8\times {{10}^{-5}},$ what is the pH of this solution? $(\log \text{ }2.7\text{ }=0.43)$                                                                                     [AIPMT (S) 2011]

A)
9.43

B)
11.72

C)
8.73

D)
9.08

• question_answer30) In qualitative analysis, the metals of group I can be separated from other ions by precipitating them as chloride salts. A solution initially contains $A{{g}^{+}}$ and $P{{b}^{2+}}$ at a concentration of 0.10 M. Aqueous HCl is added to this solution until the $C{{l}^{-}}$ concentration is 0.10 M. What will be the concentration of $A{{g}^{+}}$ and $P{{b}^{2+}}$ be at equilibrium? (${{K}_{sp}}$ for $AgCl=1.8\times {{10}^{-10}},$ ${{K}_{sp}}$ for $PbC{{l}_{2}}=1.7\times {{10}^{-5}}$)                                                                                                             [AIPMT (M) 2011]

A)
$[A{{g}^{+}}]=1.8\times {{10}^{-7}}M;[P{{b}^{2+}}]=1.7\times {{10}^{-6}}M$

B)
$[A{{g}^{+}}]=1.8\times {{10}^{-11}}M;[P{{b}^{2+}}]=8.5\times {{10}^{-5}}M$

C)
$[A{{g}^{+}}]=1.8\times {{10}^{-9}}M;[P{{b}^{2+}}]=1.7\times {{10}^{-3}}M$

D)
$[A{{g}^{+}}]=1.8\times {{10}^{-11}}M;[P{{b}^{2+}}]=8.5\times {{10}^{-4}}M$

• question_answer31) pH of a saturated solution of $Ba{{(OH)}_{2}}$ is 12. The value of solubility product K of $Ba{{(OH)}_{2}}$ is                                                                                                                                     [AIPMT (S) 2012]

A)
$3.3\times {{10}^{-7}}$

B)
$5.0\times {{10}^{-7}}$

C)
$4.0\times {{10}^{-6}}$

D)
$5.0\times {{10}^{-6}}$

• question_answer32) Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value?                                                                                                                            [AIPMT (S) 2012]

A)
$BaC{{l}_{2}}$

B)
$AlC{{l}_{3}}$

C)
$LiCl$

D)
$BeC{{l}_{2}}$

• question_answer33) Buffer solutions have constant acidity and alkalinity because                                                [AIPMT (S) 2012]

A)
these give unionised acid or base on reaction with added acid or alkali

B)
acids and alkalies in these solutions are shielded from attack by other ions

C)
they have large excess of ${{H}^{+}}$ or $O{{H}^{-}}$ ions

D)
they have fixed value of pH

• question_answer34) An excess of $AgN{{O}_{3}}$ is added to 100 mL of a 0.01 M solution of Dichlorotetraaquachromium (III) chloride. The number of moles of $\text{AgCl}$ precipitate would be                                                       [NEET 2013]

A)
0.001

B)
0.002

C)
0.003

D)
0.01

• question_answer35) Which of the following salts will give highest pH in water?                                                    [AIPMT 2014]

A)
$KCl$

B)
$NaCl$

C)
$N{{a}_{2}}C{{O}_{3}}$

D)
$CuS{{O}_{4}}$

• question_answer36) The ${{K}_{sp}}$ of $A{{g}_{2}}Cr{{O}_{4}},\,AgCl,\,AgBr$ and $AgI$ are respectively, $1.1\times {{10}^{-12}},\,\,1.8\times {{10}^{-10}}$$5.0\times {{10}^{-13}},$$8.3\times {{10}^{-17}}$. Which one of the following salts will precipitate last if $AgN{{O}_{3}}$ solution is added to the solution containing equal moles of $NaCl,NaBr,NaI$ and$N{{a}_{2}}CrC{{O}_{4}}$.                                                                                              [NEET 2015 ]

A)
$Agl$

B)
$AgCl$

C)
$AgBr$

D)
$A{{g}_{2}}Cr{{O}_{4}}$

• question_answer37) What is the pH of the resulting solution when equal volumes of 0.1 M $NaOH$ and M HCl are mixed?                                                                                                                                                    [NEET 2015 (Re)]

A)
12.65

B)
2.0

C)
7.0

D)
1.04

• question_answer38) Which one of the following pairs of solution is not an acidic buffer?                      [NEET 2015 (Re)]

A)
$HCl{{O}_{4}}$ and $NaCl{{O}_{4}}$

B)
$C{{H}_{3}}COOH$ and $C{{H}_{3}}COONa$

C)
${{H}_{2}}C{{O}_{3}}$ and $N{{a}_{2}}C{{O}_{3}}$

D)
${{H}_{3}}P{{O}_{4}}$ and $N{{a}_{2}}P{{O}_{4}}$

• question_answer39) MY and $N{{Y}_{3}},$ two nearly insoluble salts, have the same ${{K}_{sp}}$ values of $6.2\times {{10}^{13}}$ at room temperature. Which statement would be true in regard to MY and $N{{Y}_{3}}$?                 [NEET - 2016]

A)
The molar solubilities of MY and $N{{Y}_{3}}$ in water are identical.

B)
The molar solubility of MY in water is less than that of $N{{Y}_{3}}$

C)
The salts MY and $N{{Y}_{3}}$ are more soluble in 0.5 M KY than in pure water.

D)
The addition of the salt of KY to solution of MY and $N{{Y}_{3}}$ will have no effect on their solubilities.

• question_answer40) Concentration of the $A{{g}^{+}}$ ions in a saturated solution of $A{{g}_{2}}{{C}_{2}}{{O}_{4}}$ is $2.2\times {{10}^{-4}}\,mol\,{{L}^{-1}}$. Solubility product of $A{{g}_{2}}{{C}_{2}}{{O}_{4}}$ is  [NEET-2017]

A)
$5.3\times {{10}^{12}}$

B)
$~2.42\times {{10}^{8}}$

C)
$2.66\times {{10}^{12}}$

D)
$~4.5\times {{10}^{11}}$

• question_answer41)  Following solutions were prepared by mixing different volumes of NaOH and HCl of different concentrations :                                                                                                                                                                                                            [NEET - 2018] [a] $\text{60mL}\frac{\text{M}}{\text{10}}\text{HCl+40mL}\frac{\text{M}}{\text{10}}\text{NaOH}$ [b] $\text{55mL}\frac{\text{M}}{\text{10}}\text{HCl+45mL}\frac{\text{M}}{\text{10}}\text{NaOH}$ [c] $\text{75mL}\frac{\text{M}}{\text{5}}\text{HCl+25mL}\frac{\text{M}}{\text{5}}\text{NaOH}$ [d] $\text{100mL}\frac{\text{M}}{\text{10}}\text{HCl+100mL}\frac{\text{M}}{\text{10}}\text{NaOH}$ pH of which one of them will be equal to 1?

A)
d

B)
a

C)
b

D)
c

• question_answer42)  The solubility of $\text{BaS}{{\text{O}}_{\text{4}}}$ in water is $\text{2}\text{.42 }\!\!\times\!\!\text{ 1}{{\text{0}}^{\text{--3}}}\text{g}{{\text{L}}^{\text{-1}}}$ at 298 K. The value of its solubility product$\text{(}{{\text{K}}_{\text{sp}}}\text{)}$ will be [NEET - 2018] (Given molar mass of$\text{BaS}{{\text{O}}_{\text{4}}}\text{=233 g mo}{{\text{l}}^{\text{--1}}}$)

A)
$\text{1}\text{.08 }\!\!\times\!\!\text{ 1}{{\text{0}}^{\text{--14}}}\text{ mol 2}{{\text{L}}^{\text{--2}}}$

B)
$\text{1}\text{.08 }\!\!\times\!\!\text{ 1}{{\text{0}}^{\text{--12}}}\text{mo}{{\text{l}}^{\text{2}}}{{\text{L}}^{\text{--2}}}$

C)
$\text{1}\text{.08 }\!\!\times\!\!\text{ 1}{{\text{0}}^{\text{--10}}}\text{mo}{{\text{l}}^{\text{2}}}{{\text{L}}^{\text{--2}}}$

D)
$\text{1}\text{.08 }\!\!\times\!\!\text{ 1}{{\text{0}}^{\text{--8}}}\text{mo}{{\text{l}}^{\text{2}}}{{\text{L}}^{\text{--2}}}$

• question_answer43) pH of a saturated solution of $Ca{{(OH)}_{2}}$is 9. The solubility product $({{K}_{sp}})$ of $Ca{{(OH)}_{2}}$ is- [NEET 2019]

A)
$0.125\times {{10}^{15}}$

B)
$0.5\times {{10}^{10}}$

C)
$0.5\times {{10}^{15}}$

D)
$0.25\times {{10}^{10}}$

• question_answer44) Find out the solubility of $Ni{{(OH)}_{2}}$ in 0.1 M$NaOH$. Given that the ionic product of $Ni{{(OH)}_{2}}$ is $2\times {{10}^{15}}$                                 [NEET 2020]

A)
$2\times {{10}^{8}}M$

B)
$1\times {{10}^{13}}M$

C)
$1\times {{10}^{8}}M$

D)
$2\times {{10}^{13}}M$