Question 1: Palette 1/97

JEE Mains 2026 MCQ

Consider a weak base ' B ' of $\mathrm{pK}_{\mathrm{b}}=5.699$. ' $x$ ' mL of 0.02 M HCl and ' y ' mL of 0.02 M weak base ' B ' are mixed to make 100 mL of a buffer of pH 9 at $25^{\circ} \mathrm{C}$. The values of ' $x$ ' and ' $y$ ' respectively are :

[Given : $\log 2=0.3010, \log 3=0.4771, \log 5=0.699$ ]

A

$ \begin{array}{|c|c|} \hline x & y \\ \hline \hline 42.7 & 57.3 \\ \hline \end{array} $

B

$ \begin{array}{|c|c|} \hline x & y \\ \hline \hline 14.3 & 85.7 \\ \hline \end{array} $

C

$ \begin{array}{|c|c|} \hline x & y \\ \hline \hline 85.7 & 14.3 \\ \hline \end{array} $

D

$ \begin{array}{|c|c|} \hline x & y \\ \hline \hline 11.1 & 88.9 \\ \hline \end{array} $

Question 2: Palette 2/97

JEE Mains 2026 MCQ

Which of the following mixture gives a buffer solution with $\mathrm{pH}=9.25$ ?

Given : $\mathrm{pK}_{\mathrm{b}}\left(\mathrm{NH}_4 \mathrm{OH}\right)=4.75$

A

$0.5 \mathrm{M} \mathrm{NH}_4 \mathrm{OH}(0.2 \mathrm{~L})+0.2 \mathrm{M} \mathrm{HCl}(0.5 \mathrm{~L})$

B

$0.2 \mathrm{M} \mathrm{NH}_4 \mathrm{OH}(0.5 \mathrm{~L})+0.1 \mathrm{M} \mathrm{HCl}(0.5 \mathrm{~L})$

C

$0.2 \mathrm{M} \mathrm{NH}_4 \mathrm{OH}(0.4 \mathrm{~L})+0.1 \mathrm{M} \mathrm{HCl}(1 \mathrm{~L})$

D

$0.4 \mathrm{M} \mathrm{NH}_4 \mathrm{OH}(1 \mathrm{~L})+0.1 \mathrm{M} \mathrm{HCl}(1 \mathrm{~L})$

Question 3: Palette 3/97

JEE Mains 2026 MCQ

Given is a concentrated solution of a weak electrolyte $A_x B_y$ of concentration ' $c$ ' and dissociation constant ' K '. The degree of dissociation is given by :

A

$ \left[\mathrm{K} \times \mathrm{c}^{x+y-1} x^x y^y\right]^{x+y} $

B

$ \left(\frac{\mathrm{K}}{\mathrm{c}^{x+y-1} x^x y^y}\right)^{\frac{1}{x+y}} $

C

$ \left(\frac{\mathrm{c}^{x+y-1} x^x y^y}{\mathrm{~K}}\right)^{x+y} $

D

$ \left(\frac{c^{x+y-1} x^x y^y}{\mathrm{~K}}\right)^{\frac{1}{x+y}} $

Question 4: Palette 4/97

JEE Mains 2026 MCQ

$\mathrm{M}_3 \mathrm{~A}_2$ is a sparingly soluble salt of molar mass $y \mathrm{~g} \mathrm{~mol}^{-1}$ and solubility $x \mathrm{~g} \mathrm{~L}^{-1}$. The ratio of the molar concentration of the anion $\left(\mathrm{A}^{3-}\right)$ to the solubility product of the salt is

A

$\frac{1}{54} \cdot \frac{y^4}{x^4}$

B

$\frac{y^5}{108 x^4}$

C

$108 \cdot \frac{x^5}{y^5}$

D

$ \frac{1}{108} \frac{y^4}{x^4} $

Question 5: Palette 5/97

JEE Mains 2026 MCQ

Arrange the following resultant mixtures in increasing order of their pH values

A. $10 \mathrm{~mL} 0.2 \mathrm{M} \mathrm{Ca}(\mathrm{OH})_2+25 \mathrm{~mL} 0.1 \mathrm{M} \mathrm{HCl}$

B. $10 \mathrm{~mL} 0.01 \mathrm{M} \mathrm{H}_2 \mathrm{SO}_4+10 \mathrm{~mL} 0.01 \mathrm{M} \mathrm{Ca}(\mathrm{OH})_2$

C. $10 \mathrm{~mL} 0.1 \mathrm{M} \mathrm{H}_2 \mathrm{SO}_4+10 \mathrm{~mL} 0.1 \mathrm{M} \mathrm{KOH}$

Choose the correct answer from the options given below :

A

$\mathrm{B}<\mathrm{C}<\mathrm{A}$

B

$\mathrm{C}<\mathrm{A}<\mathrm{B}$

C

$\mathrm{C}<\mathrm{B}<\mathrm{A}$

D

$\mathrm{A}<\mathrm{C}<\mathrm{B}$

Question 6: Palette 6/97

JEE Mains 2026 MCQ

Given below are two statements :

Statement I : Sodium dichromate and potassium dichromate are classified as primary standards in titrimetric analysis.

Statement II : Phenolphthalein is a weak base, therefore it dissociates in acidic medium.

In the light of the above statements, choose the correct answer from the options given below

A

Both Statement I and Statement II are ture

B

Both Statement I and Statement II are false

C

Statement I is true but Statement II is false

D

Statement I is false but Statement II is true

Question 7: Palette 7/97

JEE Mains 2026 MCQ

20 mL of a solution of acetic acid required 28.4 mL of 0.1 M NaOH for its neutralization. A solution (X) was prepared by mixing 20 mL of the above acetic acid and 14.2 mL of 0.1 M NaOH solution. What is the pH of the solution $(\mathrm{X})$ ? $\left(\mathrm{pK}_{\mathrm{a}}\right.$ value of acetic acid is 4.75).

A

7.0

B

4.75

C

3.5

D

4.82

Question 8: Palette 8/97

JEE Mains 2026 MCQ

The first and second ionization constants of a weak dibasic acid H₂A are $8.1 \times 10^{-8}$ and $1.0 \times 10^{-13}$ respectively. 0.1 mol of H₂A was dissolved in 1 L of 0.1 M HCl solution. The concentration of HA^- in the resultant solution is:

A

$0.1\ \mathrm{M}$

B

$9.53 \times 10^{-6}\ \mathrm{M}$

C

$8.1 \times 10^{-8}\ \mathrm{M}$

D

$1.0 \times 10^{-13}\ \mathrm{M}$

Question 9: Palette 9/97

JEE Mains 2026 MCQ

At 25°C, 20.0 mL of 0.2 M weak monoprotic acid HX is titrated against 0.2 M NaOH. The pH of the solution (a) at the start of the titration (when NaOH has not been added) and (b) when 10 mL of NaOH is added respectively, are :

Given :
$K_a = 5 \times 10^{-4}$
$\mathrm{p}K_a = 3.3$
$\alpha \ll 1$

A

(a)	(b)
0.7	2.0

B

(a)	(b)
2.0	3.3

C

(a)	(b)
1.1	2.2

D

(a)	(b)
3.0	2.2

Question 10: Palette 10/97

JEE Mains 2026 MCQ

The solubility product constants of $\mathrm{Ag_2CrO_4}$ and $\mathrm{AgBr}$ are $32x$ and $4y$ respectively at 298 K.

The value of $\left( \frac{\text{molarity of } \mathrm{Ag_2CrO_4}}{\text{molarity of } \mathrm{AgBr}} \right)$ can be expressed as :

A

$\frac{2\sqrt[3]{x}}{y}$

B

$2 \sqrt{\frac{x}{y}}$

C

$\sqrt{\frac{x}{y}}$

D

$\frac{\sqrt[3]{x}}{\sqrt{y}}$

Question 11: Palette 11/97

JEE Mains 2025 MCQ

An aqueous solution of HCl with pH 1.0 is diluted by adding equal volume of water (ignoring dissociation of water). The pH of HCl solution would

$($ Given $\log 2=0.30)$

A

increase to 1.3

B

reduce to 0.5

C

increase to 2

D

remain same

Question 12: Palette 12/97

JEE Mains 2025 MCQ

40 mL of a mixture of $\mathrm{CH}_3 \mathrm{COOH}$ and HCl (aqueous solution) is titrated against 0.1 M NaOH solution conductometrically. Which of the following statement is correct?

A

The concentration of $\mathrm{CH}_3 \mathrm{COOH}$ in the original mixture is 0.005 M

B

The concentration of HCl in the original mixture is 0.005 M

C

$\mathrm{CH}_3 \mathrm{COOH}$ is neutralised first followed by neutralisation of HCl

D

Point ' C ' indicates the complete neutralisation of HCl

Question 13: Palette 13/97

JEE Mains 2025 MCQ

If equal volumes of $A B_2$ and $X Y$ (both are salts) aqueous solutions are mixed, which of the following combination will give a precipitate of $\mathrm{AY}_2$ at 300 K ? (Given $\mathrm{K}_{\mathrm{sp}}\left(\right.$ at 300 K ) for $\mathrm{AY}_2=5.2 \times 10^{-7}$ )

A

$2.0 \times 10^{-4} \mathrm{M} \mathrm{AB}_2, 0.8 \times 10^{-3} \mathrm{M} \mathrm{XY}$

B

$2.0 \times 10^{-2} \mathrm{M} \mathrm{AB}_2, 2.0 \times 10^{-2} \mathrm{M} \mathrm{XY}$

C

$1.5 \times 10^{-4} \mathrm{M} \mathrm{AB}_2, 1.5 \times 10^{-3} \mathrm{M} \mathrm{XY}$

D

$3.6 \times 10^{-3} \mathrm{M} \mathrm{AB}_2, 5.0 \times 10^{-4} \mathrm{M} \mathrm{XY}$

Question 14: Palette 14/97

JEE Mains 2025 MCQ

Arrange the following in increasing order of solubility product :

$\mathrm{Ca}(\mathrm{OH})_2, \mathrm{AgBr}, \mathrm{PbS}, \mathrm{HgS}$

A

$\mathrm{PbS}<\mathrm{HgS}<\mathrm{Ca}(\mathrm{OH})_2<\mathrm{AgBr}$

B

$\mathrm{HgS}<\mathrm{AgBr}<\mathrm{PbS}<\mathrm{Ca}(\mathrm{OH})_2$

C

$\mathrm{HgS}<\mathrm{PbS}<\mathrm{AgBr}<\mathrm{Ca}(\mathrm{OH})_2$

D

$\mathrm{Ca}(\mathrm{OH})_2<\mathrm{AgBr}<\mathrm{HgS}<\mathrm{PbS}$

Question 15: Palette 15/97

JEE Mains 2025 MCQ

A weak acid HA has degree of dissociation x . Which option gives the correct expression of ( pH - $\mathrm{pK}_{\mathrm{a}}$)?

A

$\log \left(\frac{1-x}{x}\right)$

B

$0$

C

$\log (1+2 \mathrm{x})$

D

$\log \left(\frac{x}{1-x}\right)$

Question 16: Palette 16/97

JEE Mains 2025 MCQ

$\mathrm{K}_{\mathrm{sp}}$ for $\mathrm{Cr}(\mathrm{OH})_3$ is $1.6 \times 10^{-30}$. What is the molar solubility of this salt in water?

A

$\sqrt[5]{1.8 \times 10^{-30}}$

B

$\frac{1.8 \times 10^{-30}}{27}$

C

$\sqrt[4]{\frac{1.6 \times 10^{-30}}{27}}$

D

$\sqrt[2]{1.6 \times 10^{-30}}$

Question 17: Palette 17/97

JEE Mains 2025 MCQ

pH of water is 7 at $25^{\circ} \mathrm{C}$. If water is heated to $80^{\circ} \mathrm{C}$., it's pH will :

A

Decrease

B

Remains the same

C

Increase

D

$\mathrm{H}^{+}$concentration increases, $\mathrm{OH}^{-}$concentration decreases

Question 18: Palette 18/97

JEE Mains 2025 MCQ

Which of the following happens when $\mathrm{NH}_4 \mathrm{OH}$ is added gradually to the solution containing 1 M $\mathrm{A}^{2+}$ and $1 \mathrm{M} \mathrm{B}^{3+}$ ions?

Given : $\mathrm{K}_{\text {sp }}\left[\mathrm{A}(\mathrm{OH})_2\right]=9 \times 10^{-10}$ and $\mathrm{K}_{\mathrm{sp}}\left[\mathrm{B}(\mathrm{OH})_3\right]=27 \times 10^{-18}$ at 298 K.

A

$\mathrm{A}(\mathrm{OH})_2$ will precipitate before $\mathrm{B}(\mathrm{OH})_3$

B

$\mathrm{A}(\mathrm{OH})_2$ and $\mathrm{B}(\mathrm{OH})_3$ will precipitate together

C

Both $\mathrm{A}(\mathrm{OH})_2$ and $\mathrm{B}(\mathrm{OH})_3$ do not show precipitation with $\mathrm{NH}_4 \mathrm{OH}$

D

$\mathrm{B}(\mathrm{OH})_3$ will precipitate before $\mathrm{A}(\mathrm{OH})_2$

Question 19: Palette 19/97

JEE Mains 2025 MCQ

The molar solubility(s) of zirconium phosphate with molecular formula $\left(\mathrm{Zr}^{4+}\right)_3\left(\mathrm{PO}_4^{3-}\right)_4$ is given by relation :

A

$\left(\frac{\mathrm{K}_{\mathrm{sp}}}{5348}\right)^{\frac{1}{6}}$

B

$\left(\frac{\mathrm{K}_{\mathrm{sp}}}{8435}\right)^{\frac{1}{7}}$

C

$\left(\frac{K_{s p}}{6912}\right)^{\frac{1}{7}}$

D

$\left(\frac{\mathrm{K}_{\mathrm{sp}}}{9612}\right)^{\frac{1}{3}}$

Question 20: Palette 20/97

JEE Mains 2024 MCQ

For a sparingly soluble salt $\mathrm{AB}_2$, the equilibrium concentrations of $\mathrm{A}^{2+}$ ions and $B^{-}$ ions are $1.2 \times 10^{-4} \mathrm{M}$ and $0.24 \times 10^{-3} \mathrm{M}$, respectively. The solubility product of $\mathrm{AB}_2$ is :

A

$0.069 \times 10^{-12}$

B

$0.276 \times 10^{-12}$

C

$6.91 \times 10^{-12}$

D

$27.65 \times 10^{-12}$

Question 21: Palette 21/97

JEE Mains 2024 MCQ

Given below are two statements :

Statement (I) : A Buffer solution is the mixture of a salt and an acid or a base mixed in any particular quantities

Statement (II) : Blood is naturally occurring buffer solution whose $\mathrm{pH}$ is maintained by $\mathrm{H}_2 \mathrm{CO}_3 / \mathrm{HCO}_3{ }^{\ominus}$ concentrations.

In the light of the above statements, choose the correct answer from the options given below :

A

Both Statement I and Statement II are false

B

Both Statement I and Statement II are true

C

Statement I is false but Statement II is true

D

Statement I is true but Statement II is false

Question 22: Palette 22/97

JEE Mains 2024 MCQ

The equilibrium $\mathrm{Cr}_2 \mathrm{O}_7^{2-} \rightleftharpoons 2 \mathrm{CrO}_4^{2-}$ is shifted to the right in :

A

a weakly acidic medium

B

a basic medium

C

a neutral medium

D

an acidic medium

Question 23: Palette 23/97

JEE Mains 2024 MCQ

Solubility of calcium phosphate (molecular mass, M) in water is $\mathrm{W_{g}}$ per $100 \mathrm{~mL}$ at $25^{\circ} \mathrm{C}$. Its solubility product at $25^{\circ} \mathrm{C}$ will be approximately.

A

$10^7\left(\frac{W}{M}\right)^3$

B

$10^3\left(\frac{\mathrm{W}}{\mathrm{M}}\right)^5$

C

$10^7\left(\frac{W}{M}\right)^5$

D

$10^5\left(\frac{\mathrm{W}}{\mathrm{M}}\right)^5$

Question 24: Palette 24/97

JEE Mains 2024 MCQ

Given below are two statements :

Statement (I) : Aqueous solution of ammonium carbonate is basic.

Statement (II) : Acidic/basic nature of salt solution of a salt of weak acid and weak base depends on $K_a$ and $K_b$ value of acid and the base forming it.

In the light of the above statements, choose the most appropriate answer from the options given below :

A

Both Statement I and Statement II are correct

B

Statement I is correct but Statement II is incorrect

C

Both Statement I and Statement II are incorrect

D

Statement I is incorrect but Statement II is correct

Question 25: Palette 25/97

JEE Mains 2023 MCQ

Which of the following statement(s) is/are correct?

(A) The $\mathrm{pH}$ of $1 \times 10^{-8}~ \mathrm{M} ~\mathrm{HCl}$ solution is 8 .

(B) The conjugate base of $\mathrm{H}_{2} \mathrm{PO}_{4}^{-}$ is $\mathrm{HPO}_{4}^{2-}$.

(C) $\mathrm{K}_{\mathrm{w}}$ increases with increase in temperature.

(D) When a solution of a weak monoprotic acid is titrated against a strong base at half neutralisation point, $\mathrm{pH}=\frac{1}{2} \mathrm{pK}_{\mathrm{a}}$

Choose the correct answer from the options given below:

A

$(\mathrm{A}),(\mathrm{B}),(\mathrm{C})$

B

(B), (C)

C

(B), (C), (D)

D

(A), (D)

Question 26: Palette 26/97

JEE Mains 2023 MCQ

$25 \mathrm{~mL}$ of silver nitrate solution (1M) is added dropwise to $25 \mathrm{~mL}$ of potassium iodide $(1.05 \mathrm{M})$ solution. The ion(s) present in very small quantity in the solution is/are :

A

$\mathrm{I^-}$ only

B

$\mathrm{K^+}$ only

C

$\mathrm{Ag^+}$ and $\mathrm{I^-}$ both

D

$\mathrm{NO_3^-}$ only

Question 27: Palette 27/97

JEE Mains 2023 MCQ

The incorrect statement for the use of indicators in acid-base titration is :

A

Phenolphthalein is a suitable indicator for a weak acid vs strong base titration.

B

Methyl orange may be used for a weak acid vs weak base titration.

C

Methyl orange is a suitable indicator for a strong acid vs weak base titration.

D

Phenolphthalein may be used for a strong acid vs strong base titration.

Question 28: Palette 28/97

JEE Mains 2023 MCQ

When the hydrogen ion concentration [H$^+$] changes by a factor of 1000, the value of pH of the solution __________

A

decreases by 2 units

B

increases by 2 units

C

decreases by 3 units

D

increases by 1000 units

Question 29: Palette 29/97

JEE Mains 2022 MCQ

$200 \mathrm{~mL}$ of $0.01 \,\mathrm{M} \,\mathrm{HCl}$ is mixed with $400 \mathrm{~mL}$ of $0.01 \,\mathrm{M} \,\mathrm{H}_{2} \mathrm{SO}_{4}$. The $\mathrm{pH}$ of the mixture is _________.

Given: $\log {2}=0.30, \log 3=0.48, \log 5=0.70, \log 7=0.84, \log 11=1.04$

A

1.14

B

1.78

C

2.34

D

3.02

Question 30: Palette 30/97

JEE Mains 2022 MCQ

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R

Assertion A : Permanganate titrations are not performed in presence of hydrochloric acid.

Reason R : Chlorine is formed as a consequence of oxidation of hydrochloric acid.

In the light of the above statements, choose the correct answer from the options given below

A

Both $\mathrm{A}$ and $\mathrm{R}$ are true and $\mathrm{R}$ is the correct explanation of $\mathrm{A}$

B

Both $\mathrm{A}$ and $\mathrm{R}$ are true but $\mathrm{R}$ is NOT the correct explanation of $\mathrm{A}$

C

$\mathrm{A}$ is true but $\mathrm{R}$ is false

D

$\mathrm{A}$ is false but $\mathrm{R}$ is true

Question 31: Palette 31/97

JEE Mains 2022 MCQ

The plot of $\mathrm{pH}$-metric titration of weak base $\mathrm{NH}_{4} \mathrm{OH}$ vs strong acid HCl looks like :

A

B

C

D

Question 32: Palette 32/97

JEE Mains 2022 MCQ

Class XII students were asked to prepare one litre of buffer solution of $\mathrm{pH} \,8.26$ by their Chemistry teacher: The amount of ammonium chloride to be dissolved by the student in $0.2\, \mathrm{M}$ ammonia solution to make one litre of the buffer is :

(Given: $\mathrm{pK}_{\mathrm{b}}\left(\mathrm{NH}_{3}\right)=4.74$

Molar mass of $\mathrm{NH}_{3}=17 \mathrm{~g} \mathrm{~mol}^{-1}$

Molar mass of $\mathrm{NH}_{4} \mathrm{Cl}=53.5 \mathrm{~g} \mathrm{~mol}^{-1}$ )

A

53.5 g

B

72.3 g

C

107.0 g

D

126.0 g

Question 33: Palette 33/97

JEE Mains 2022 MCQ

${K_{{a_1}}}$, ${K_{{a_2}}}$ and ${K_{{a_3}}}$ are the respective ionization constants for the following reactions (a), (b) and (c).

(a) ${H_2}{C_2}{O_4} \mathbin{\lower.3ex\hbox{$\buildrel\textstyle\rightarrow\over {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}}$}} {H^ + } + H{C_2}O_4^ - $

(b) $H{C_2}O_4^ - \mathbin{\lower.3ex\hbox{$\buildrel\textstyle\rightarrow\over {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}}$}} {H^ + } + {C_2}O_4^{2 - }$

(c) ${H_2}{C_2}O_4^{} \mathbin{\lower.3ex\hbox{$\buildrel\textstyle\rightarrow\over {\smash{\leftarrow}\vphantom{_{\vbox to.5ex{\vss}}}}$}} 2{H^ + } + {C_2}O_4^{2 - }$

The relationship between ${K_{{a_1}}}$, ${K_{{a_2}}}$ and ${K_{{a_3}}}$ is given as :

A

${K_{{a_3}}}$ $=$ ${K_{{a_1}}}$ $+$ ${K_{{a_2}}}$

B

${K_{{a_3}}}$ $=$ ${K_{{a_1}}}$ $-$ ${K_{{a_2}}}$

C

${K_{{a_3}}}$ $=$ ${K_{{a_1}}}$ $/$ ${K_{{a_2}}}$

D

${K_{{a_3}}}$ $=$ ${K_{{a_1}}}$ $\times$ ${K_{{a_2}}}$

Question 34: Palette 34/97

JEE Mains 2022 MCQ

$20 \mathrm{~mL}$ of $0.1\, \mathrm{M} \,\mathrm{NH}_{4} \mathrm{OH}$ is mixed with $40 \mathrm{~mL}$ of $0.05 \mathrm{M} \mathrm{HCl}$. The $\mathrm{pH}$ of the mixture is nearest to :

(Given : $\mathrm{K}_{\mathrm{b}}\left(\mathrm{NH}_{4} \mathrm{OH}\right)=1 \times 10^{-5}, \log 2=0.30, \log 3=0.48, \log 5=0.69, \log 7=0.84, \log 11= 1.04)$

A

3.2

B

4.2

C

5.2

D

6.2

Question 35: Palette 35/97

JEE Mains 2022 MCQ

The solubility of AgCl will be maximum in which of the following?

A

0.01 M KCl

B

0.01 M HCl

C

0.01 M AgNO₃

D

Deionised water

Question 36: Palette 36/97

JEE Mains 2022 MCQ

A student needs to prepare a buffer solution of propanoic acid and its sodium salt with pH 4. The ratio of ${{[C{H_3}C{H_2}CO{O^ - }]} \over {[C{H_3}C{H_2}COOH]}}$ required to make buffer is ___________.

Given : ${K_a}(C{H_3}C{H_2}COOH) = 1.3 \times {10^{ - 5}}$

A

0.03

B

0.13

C

0.23

D

0.33

Question 37: Palette 37/97

JEE Mains 2022 MCQ

The K_sp for bismuth sulphide (Bi₂S₃) is 1.08 $\times$ 10^$-$73. The solubility of Bi₂S₃ in mol L^$-$1 at 298 K is :

A

1.0 $\times$ 10^$-$15

B

2.7 $\times$ 10^$-$12

C

3.2 $\times$ 10^$-$10

D

4.2 $\times$ 10^$-$8

Question 38: Palette 38/97

JEE Mains 2022 MCQ

Given below are two statements one is labelled as Assertion A and the other is labelled as Reason R :

Assertion A : The amphoteric nature of water is explained by using Lewis acid/base concept.

Reason R : Water acts as an acid with NH₃ and as a base with H₂S.

In the light of the above statements choose the correct answer from the options given below :

A

Both A and R are true and R is the correct explanation of A.

B

Both A and R are true but R is NOT the correct explanation of A.

C

A is true but R is false.

D

A is false but R is true.

Question 39: Palette 39/97

JEE Mains 2021 MCQ

Given below are two statements.

Statement I : In the titration between strong acid and weak base methyl orange is suitable as an indicator.

Statement II : For titration of acetic acid with NaOH phenolphthalein is not a suitable indicator.

In the light of the above statements, choose the most appropriate answer from the options given below :

A

Statement I is false but Statement II is true

B

Statement I is true but Statement II is false

C

Both Statement I and Statement II are true

D

Both Statement I and Statement II are false

Question 40: Palette 40/97

JEE Mains 2021 MCQ

A solution is 0.1 M in Cl^$-$ and 0.001 M in CrO$_4^{2 - }$. Solid AgNO₃ is gradually added to it. Assuming that the addition does not change in volume and K_sp(AgCl) = 1.7 $\times$ 10^$-$10 M² and K_sp(Ag₂CrO₄) = 1.9 $\times$ 10^$-$12 M³.

Select correct statement from the following :

A

AgCl precipitates first because its K_sp is high.

B

Ag₂CrO₄ precipitates first as its K_sp is low.

C

Ag₂CrO₄ precipitates first because the amount of Ag⁺ needed is low.

D

AgCl will precipitate first as the amount of Ag⁺ needed to precipitate is low.

Question 41: Palette 41/97

JEE Mains 2021 MCQ

Given below are two statements : One is labelled as Assertion A and the other labelled as reason R

Assertion A : During the boiling of water having temporary hardness, Mg(HCO₃)₂ is converted to MgCO₃.

Reason R : The solubility product of Mg(OH)₂ is greater than that of MgCO₃.

In the light of the above statements, choose the most appropriate answer from the options given below :

A

Both A and R are true but R is not the correct explanation of A

B

A is true but R is false

C

Both A and R are true and R is the correct explanation of A

D

A is false but R is true

Question 42: Palette 42/97

JEE Mains 2021 MCQ

Which of the following compound CANNOT act as a Lewis base?

A

SF₄

B

NF₃

C

ClF₃

D

PCl₅

Question 43: Palette 43/97

JEE Mains 2021 MCQ

The solubility of Ca(OH)₂ in water is :

[Given : The solubility product of Ca(OH)₂ in water = 5.5 $\times$ 10^$-$6]

A

1.11 $\times$ 10^$-$6

B

1.11 $\times$ 10^$-$2

C

1.77 $\times$ 10^$-$6

D

1.77 $\times$ 10^$-$2

Question 44: Palette 44/97

JEE Mains 2021 MCQ

The solubility of AgCN in a buffer solution of pH = 3 is x. The value of x is : [Assume : No cyano complex is formed; K_sp(AgCN) = 2.2 $\times$ 10^$-$16 and K_a(HCN) = 6.2 $\times$ 10^$-$10]

A

1.9 $\times$ 10^$-$5

B

1.6 $\times$ 10^$-$6

C

2.2 $\times$ 10^$-$16

D

0.625 $\times$ 10^$-$6

Question 45: Palette 45/97

JEE Mains 2020 MCQ

Arrange the following solutions in the decreasing order of pOH :

(A) 0.01 M HCl
(B) 0.01 M NaOH
(C) 0.01 M CH₃COONa
(D) 0.01 M NaCl

A

(B) > (C) > (D) > (A)

B

(A) > (D) > (C) > (B)

C

(A) > (C) > (D) > (B)

D

(B) > (D) > (C) > (A)

Question 46: Palette 46/97

JEE Mains 2020 MCQ

100 mL of 0.1 M HCl is taken in a beaker and to it 100 mL of 0.1 M NaOH is added in steps of 2 mL and the pH is continuously measured. Which of the following graphs correctly depicts the change in pH?

A

B

C

D

Question 47: Palette 47/97

JEE Mains 2020 MCQ

An acidic buffer is obtained on mixing :

A

100 mL of 0.1 M HCl and 200 mL of 0.1 M CH₃COONa

B

100 mL of 0.1 M HCl and 200 mL of 0.1 M NaCl

C

100 mL of 0.1 M CH₃COOH and 100 mL of 0.1 M NaOH

D

100 mL of 0.1 M CH₃COOH and 200 mL of 0.1 M NaOH

Question 48: Palette 48/97

JEE Mains 2020 MCQ

For the following Assertion and Reason, the correct option is

Assertion (A): When Cu (II) and sulphide ions are mixed, they react together extremely quickly to give a solid.

Reason (R): The equilibrium constant of
Cu²⁺(aq) + S^2–(aq) ⇌ CuS(s) is high because the solubility product is low.

A

(A) is false and (R) is true.

B

Both (A) and (R) are true but (R) is not the explanation for (A).

C

Both (A) and (R) are true and (R) is the explanation for (A).

D

Both (A) and (R) are false.

Question 49: Palette 49/97

JEE Mains 2020 MCQ

The solubility product of Cr(OH)₃ at 298 K is 6.0 × 10^–31. The concentration of hydroxide ions in a saturated solution of Cr(OH)₃ will be :

A

(2.22 × 10^–31)^1/4

B

(4.86 × 10^–29)^1/4

C

(18 × 10^–31)^1/4

D

(18 × 10^–31)^1/2

Question 50: Palette 50/97

JEE Mains 2020 MCQ

The K_sp for the following dissociation is 1.6 × 10^–5

$PbC{l_{2(s)}} \leftrightharpoons Pb_{(aq)}^{2 + } + 2Cl_{(aq)}^ - $

Which of the following choices is correct for a mixture of 300 mL 0.134 M Pb(NO₃)₂ and 100 mL 0.4 M NaCl ?

A

Q > K_sp

B

Not enough data provided

C

Q < K_sp

D

Q = K_sp

Question 51: Palette 51/97

JEE Mains 2020 MCQ

For the following Assertion and Reason, the correct option is :

Assertion : The pH of water increases with increase in temperature.

Reason : The dissociation of water into H⁺ and OH^– is an exothermic reaction.

A

Both assertion and reason are false.

B

Both assertion and reason are true, but the reason is not the correct explanation for the assertion.

C

Both assertion and reason are true, and the reason is the correct explanation for the assertion.

D

Assertion is not true, but reason is true.

Question 52: Palette 52/97

JEE Mains 2020 MCQ

The strength of an aqueous NaOH solution is most accurately determined by titrating :
(Note : consider that an appropriate indicator is used)

A

Aq. NaOH in a pipette and aqueous oxalic acid in a burette

B

Aq. NaOH in a burette and aqueous oxalic acid in a conical flask

C

Aq. NaOH in a volumetric flask and concentrated H₂SO₄ in a conical flask

D

Aq. NaOH in a burette and concentrated H₂SO₄ in a conical flask

Question 53: Palette 53/97

JEE Mains 2020 MCQ

The stoichiometry and solubility product of a salt with the solubility curve given below is, respectively :

A

XY, 2 × 10^–6 M³

B

XY₂, 1 × 10^–9 M³

C

XY₂, 4 × 10^–9 M³

D

X₂Y, 2 × 10^–9 M³

Question 54: Palette 54/97

JEE Mains 2019 MCQ

The decreasing order of electrical conductivity of the following aqueous solutions is :

0.1 M Formic acid (A),

0.1 M Acetic acid (B),

0.1 M Benzoic acid (C)

A

A > B > C

B

C > B > A

C

A > C > B

D

C > A > B

Question 55: Palette 55/97

JEE Mains 2019 MCQ

The molar solubility of Cd(OH)₂ is 1.84 × 10^–5 M in water. The expected solubility of Cd(OH)₂ in a buffer solution of pH = 12 is :

A

2.49 × 10^–10 M

B

1.84 × 10^–9 M

C

6.23 × 10^–11 M

D

${{2.49} \over {1.84}} \times {10^{ - 9}}M$

Question 56: Palette 56/97

JEE Mains 2019 MCQ

What is the molar solubility of Al(OH)₃ in 0.2 M NaOH solution ? Given that, solubility product of Al(OH)₃ = 2.4 × 10^–24 :

A

3 × 10^–22

B

3 × 10^–19

C

12 × 10^–21

D

12 × 10^–22

Question 57: Palette 57/97

JEE Mains 2019 MCQ

The pH of a 0.02 M NH₄Cl solution will be :
[given K_b (NH₄OH) = 10^–5 and log 2 = 0.301]

A

2.56

B

5.35

C

4.35

D

4.65

Question 58: Palette 58/97

JEE Mains 2019 MCQ

Consider the following statements
(a) The pH of a mixture containing 400 mL of 0.1 M H₂SO₄ and 400 mL of 0.1 M NaOH will be approximately 1.3
(b) Ionic product of water is temperature dependent.
(c) A monobasic acid with Ka = 10^–5 has pH = 5. The degree of dissociation of this acid is 50 %.
(d) The Le Chatelier's principle is not applicable to common-ion effect.

The correct statements are :

A

(a) and (b)

B

(a), (b) and (c)

C

(a), (b) and (d)

D

(b) and (c)

Question 59: Palette 59/97

JEE Mains 2019 MCQ

In an acid-base titration, 0.1 M HCl solution was added to the NaOH solution of unknown strength. Which of the following correctly shows the change of pH of the titraction mixture in this experiment?

A

(C)

B

(A)

C

(B)

D

(D)

Question 60: Palette 60/97

JEE Mains 2019 MCQ

If solublity product of Zr₃(PO₄)₄ is denoted by K_sp and its molar solubility is denoted by S, then which of the following relation between S and K_sp is correct ?

A

$S = {\left( {{{{K_{sp}}} \over {929}}} \right)^{1/9}}$

B

$S = {\left( {{{{K_{sp}}} \over {6912}}} \right)^{1/7}}$

C

$S = {\left( {{{{K_{sp}}} \over {144}}} \right)^{1/6}}$

D

$S = {\left( {{{{K_{sp}}} \over {216}}} \right)^{1/7}}$

Question 61: Palette 61/97

JEE Mains 2019 MCQ

If K_sp of Ag₂CO₃ is 8 $ \times $ 10^–12, the molar solubility of Ag₂CO₃ in 0.1 M AgNO₃ is -

A

8 $ \times $ 10^–12 M

B

8 $ \times $ 10^–10 M

C

8 $ \times $ 10^–13 M

D

8 $ \times $ 10^–11 M

Question 62: Palette 62/97

JEE Mains 2019 MCQ

A mixture of 100 m mol of Ca(OH)₂ and 2 g of sodium sulphate was dissolved in water and the volume was made up to 100 mL. The mass of calcium sulphate formed and the concentration of OH^– in resulting solution, respectively, are : (Molar mass of Ca (OH)₂, Na₂SO₄ and CaSO₄ are 74, 143 and 136 g mol^–1 , respectively; K_sp of Ca(OH)₂ is 5.5 × 10^–6 )

A

13.6g, 0.28 mol L^$-$1

B

13.6g, 0.14 mol L^$-$1

C

1.9g, 0.28 mol L^$-$1

D

1.9g, 0.14 mol L^$-$1

Question 63: Palette 63/97

JEE Mains 2019 MCQ

The pH of rain water, is approximately :

A

5.6

B

7.5

C

7.0

D

6.5

Question 64: Palette 64/97

JEE Mains 2019 MCQ

20 mL of 0.1 M H₂SO₄ solution is added to 30 mL of of 0.2 M NH₄OH solution. The pH of the resultant mixture is : [pk_b of NH₄OH = 4.7].

A

5.2

B

9.0

C

5.0

D

9.4

Question 65: Palette 65/97

JEE Mains 2018 MCQ

An alkali is titrated against an acid with methyl orange as indicator, which of the following is a correct combination?

A

Base	Acid	End point
Weak	Strong	Colourless to pink

B

Base	Acid	End point
Strong	Strong	Pinkish red to yellow

C

Base	Acid	End point
Weak	Strong	Yellow to pinkish red

D

Base	Acid	End point
Strong	Strong	Pink to colourless

Question 66: Palette 66/97

JEE Mains 2018 MCQ

Which of the following salts is the most basic in aqueous solution?

A

Pb(CH₃COO)₂

B

Al(CN)₃

C

CH₃COOK

D

FeCl₃

Question 67: Palette 67/97

JEE Mains 2018 MCQ

An aqueous solution contains an unknown concentration of Ba²⁺. When 50 mL of a 1 M solution of Na₂SO₄ is added, BaSO₄ just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO₄ is 1 $\times$ 10^–10. What is the original concentration of Ba²⁺?

A

1.0 $\times$ 10^–10 M

B

5 $\times$ 10^–9 M

C

2 $\times$ 10^–9 M

D

1.1 $\times$ 10^–9 M

Question 68: Palette 68/97

JEE Mains 2018 MCQ

Which of the following are Lewis acids?

A

BCl₃ and AlCl₃

B

PH₃ and BCl₃

C

AlCl₃ and SiCl₄

D

PH₃ and SiCl₄

Question 69: Palette 69/97

JEE Mains 2018 MCQ

An aqueous solution contains 0.10 M H₂S and 0.20 M HCl. If the equilibrium constants for the formation of HS^– from H₂S is 1.0 $\times$ 10^–7 and that of S^2- from HS^– ions is 1.2 $\times$ 10^–13 then the concentration of S^2- ions in aqueous solution is :

A

5 $\times$ 10^–19

B

5 $\times$ 10^–8

C

3 $\times$ 10^–20

D

6 $\times$ 10^–21

Question 70: Palette 70/97

JEE Mains 2018 MCQ

Following four solutions are prepared by mixing different volumes of NaOH and HCl of different concentrations, pH of which one of them will be equal to 1 ?

A

100 mL ${M \over {10}}$ HCl + 100 mL ${M \over {10}}$ NaOH

B

75 mL ${M \over {5}}$ HCl + 25 mL ${M \over {5}}$ NaOH

C

60 mL ${M \over {10}}$ HCl + 40 mL ${M \over {10}}$ NaOH

D

55 mL ${M \over {10}}$ HCl + 45 mL ${M \over {10}}$ NaOH

Question 71: Palette 71/97

JEE Mains 2018 MCQ

The minimum volume of water required to dissolve 0.1 g lead (II) chloride to get a saturated solution (K_sp of PbCl₂ = 3.2 $ \times $ 10^-8 atomic mass of Pb = 207 u ) is :

A

0.36 L

B

17.98 L

C

0.18 L

D

1.798 L

Question 72: Palette 72/97

JEE Mains 2018 MCQ

Which of the following is a Lewis acid?

A

PH₃

B

B(CH₃)₃

C

NaH

D

NF₃

Question 73: Palette 73/97

JEE Mains 2017 MCQ

50 mL of 0.2 M ammonia solution is treated with 25 mL of 0.2 M HCl. If pK_b of ammonia solution is 4.75, the pH of the mixture will be :

A

3.75

B

4.75

C

8.25

D

9.25

Question 74: Palette 74/97

JEE Mains 2017 MCQ

Additin of sodium hydroxide solution to a weak acid (HA)results in a buffer of pH 6. If ionition constant of HA is 10^$-$5, the ratio of salt to acid concentration in the buffer solution will be :

A

4 : 5

B

1 : 10

C

10 : 1

D

5 : 4

Question 75: Palette 75/97

JEE Mains 2017 MCQ

pK_a of a weak acid (HA) and pK_b of a weak base (BOH) are 3.2 and 3.4, respectively. The pH of their salt (AB) solution is :

A

6.9

B

7.0

C

1.0

D

7.2

Question 76: Palette 76/97

JEE Mains 2013 MCQ

How many litres of water must be added to 1 litre of an aqueous solution of HCl with a pH of 1 to create an aqueous solution with pH of 2?

A

0.1 L

B

0.9 L

C

2.0 L

D

9.0 L

Question 77: Palette 77/97

JEE Mains 2012 MCQ

The pH of a 0.1 molar solution of the acid HQ is 3. The value of the ionization constant, K_a of this acid is :

A

3 $\times$ 10^–1

B

1 $\times$ 10^–3

C

1 $\times$ 10^–5

D

1 $\times$ 10^–7

Question 78: Palette 78/97

JEE Mains 2010 MCQ

Three reactions involving $H_2PO_4^−$ are given below :

(i) H₃PO₄ + H₂O $\to$ H₃O⁺ + $H_2PO_4^−$

(ii) $H_2PO_4^−$ + H₂O $\to$ $HPO_4^{2−}$ + H₃O⁺

(iii) $H_2PO_4^−$ + OH^- $\to$H₃PO₄ + O^2-

In which of the above does $H_2PO_4^−$ act as an acid?

A

(ii) only

B

(i) and (ii)

C

(iii) only

D

(i) only

Question 79: Palette 79/97

JEE Mains 2010 MCQ

Solubility product of silver bromide is 5.0 $\times$ 10^–13. The quantity of potassium bromide (molar mass taken as 120g of mol^–1) to be added to 1 litre of 0.05 M solution of silver nitrate to start the precipitation of AgBr is :

A

1.2 $\times$ 10^–10 g

B

1.2 $\times$ 10^–9 g

C

6.2 $\times$ 10^–5 g

D

5.0 $\times$ 10^–8 g

Question 80: Palette 80/97

JEE Mains 2010 MCQ

At 25°C, the solubility product of Mg(OH)₂ is 1.0 $\times$ 10^–11. At which pH, will Mg²⁺ ions start precipitating in the form of Mg(OH)₂ from a solution of 0.001 M Mg²⁺ ions?

A

9

B

10

C

11

D

8

Question 81: Palette 81/97

JEE Mains 2009 MCQ

Solid Ba(NO₃)₂ is gradually dissolved in a 1.0 $\times$ 10^-4 M Na₂CO₃ solution. At what concentration of Ba²⁺ will a precipitate begin to form ?
(K_sp for BaCO₃ = 5.1 $\times$ 10⁻⁹ )

A

5.1 $\times$ 10^-5 M

B

8.1 $\times$ 10^-8 M

C

8.1 $\times$ 10^-7 M

D

4.1 $\times$ 10^-5 M

Question 82: Palette 82/97

JEE Mains 2008 MCQ

The pK_a of a weak acid, HA, is 4.80. The pK_b of a weak base, BOH, is 4.78. The pH of an aqueous solution of the corresponding salt, BA, will be

A

9.58

B

4.79

C

7.01

D

9.22

Question 83: Palette 83/97

JEE Mains 2008 MCQ

Four species are listed below
i. $HCO_3^−$
ii. $H_3O^+$
iii. $HSO_4^−$
iv. $HSO_3F$
Which one of the following is the correct sequence of their acid strength?

A

iv < ii < iii < I

B

ii < iii < i < iv

C

i < iii < ii < iv

D

iii < i < iv < ii

Question 84: Palette 84/97

JEE Mains 2007 MCQ

The pK_a of a weak acid (HA) is 4.5. The pOH of an aqueous buffered solution of HA in which 50% of the acid is ionized is :

A

7.0

B

4.5

C

2.5

D

9.5

Question 85: Palette 85/97

JEE Mains 2007 MCQ

The first and second dissociation constants of an acid H₂A are 1.0 $\times$ 10⁻⁵ and 5.0 $\times$ 10⁻¹⁰ respectively. The overall dissociation constant of the acid will be :

A

5.0 $\times$ 10⁻⁵

B

5.0 $\times$ 10¹⁵

C

5.0 $\times$ 10⁻¹⁵

D

5.0 $\times$ 10⁵

Question 86: Palette 86/97

JEE Mains 2007 MCQ

In a sautrated solution of the sparingly soluble strong electrolyte AgIO₃ (Molecular mass = 283) the equilibrium which sets in is
AgIO_3(s) $\leftrightharpoons$ Ag⁺(aq) + $IO_3^-$
If the solubility product constant K_sp of AgIO₃ at a given temperature is 1.0 $\times$10⁻⁸, what is the mass of AgIO₃ contained in 100 ml of its saturated solution?

A

28.3 × 10⁻² g

B

2.83 × 10⁻³ g

C

1.0 × 10⁻⁷ g

D

1.0 × 10⁻⁴ g

Question 87: Palette 87/97

JEE Mains 2005 MCQ

What is the conjugate base of OH^-?

A

O₂

B

H₂O

C

O^-

D

O^-2

Question 88: Palette 88/97

JEE Mains 2005 MCQ

The solubility product of a salt having general formula MX₂, in water is: 4 $\times$ 10^-12 . The concentration of M²⁺ ions in the aqueous solution of the salt is :

A

2.0 $\times$ 10^-6 M

B

4.0 $\times$ 10^-10 M

C

1.0 $\times$ 10^-4 M

D

1.6 $\times$ 10^-4 M

Question 89: Palette 89/97

JEE Mains 2005 MCQ

Hydrogen ion concentration in mol / L in a solution of pH = 5.4 will be :

A

3.98 $\times$ 10^-6

B

3.68 $\times$ 10^-6

C

3.88 $\times$ 10⁶

D

3.98 $\times$ 10⁸

Question 90: Palette 90/97

JEE Mains 2004 MCQ

The molar solubility (in ol L^-1) of a sparingly soluble salt MX₄ is "s". The corresponding solubility product is K_sp. 's' is given in term of K_sp by the relation :

A

s = (256 K_sp)^1/5

B

s = (128 K_sp)^1/4

C

s = ( K_sp / 128)^1/4

D

s = (K_sp / 256)^1/5

Question 91: Palette 91/97

JEE Mains 2004 MCQ

The conjugate base of H₂PO₄^- is :

A

$PO_4^{3-}$

B

$HPO_4^{2-}$

C

H₃PO₄

D

P₂O₅

Question 92: Palette 92/97

JEE Mains 2003 MCQ

Which one of the following statements is not true?

A

pH + pOH = 14 for all aqueous solutions

B

The pH of 1 $\times$ 10^-8 M HCl is 8

C

96,500 coulombs of electricity when passed through a CuSO₄ solution deposits 1 gram equivalent of copper at the cathode

D

The conjugate base of $H_2PO_4^-$ is $HPO_4^{2-}$

Question 93: Palette 93/97

JEE Mains 2003 MCQ

The solubility in water of a sparingly soluble salt AB₂ is 1.0 $\times$ 10^-5 mol L^-1. Its solubility product number will be :

A

4 $\times$ 10^-10

B

1 $\times$ 10^-15

C

1 $\times$ 10^-10

D

4 $\times$ 10^-15

Question 94: Palette 94/97

JEE Mains 2003 MCQ

When rain is accompanied by a thunderstorm, the collected rain water will have a pH value :

A

slightly higher than that when the thunderstorm is not there

B

uninfluenced by occurence of thunderstorm

C

which depends on the amount of dust in air

D

slightly lower than that of rain water without thunderstorm

Question 95: Palette 95/97

JEE Mains 2002 MCQ

Species acting as both Bronsted acid and base is :

A

(HSO₄)^-1

B

Na₂CO₃

C

NH₃

D

OH^-1

Question 96: Palette 96/97

JEE Mains 2002 MCQ

Let the solubility of an aqueous solution of Mg(OH)₂ be x then its K_sp is :

A

4x³

B

108x⁵

C

27x⁴

D

9x

Question 97: Palette 97/97

JEE Mains 2002 MCQ

1 M NaCL and 1 M HCL are present in an aqueous solution. The solution is

A

not a buffer solution with pH < 7

B

not a buffer solution with pH > 7

C

a buffer solution with pH < 7

D

a buffer solution with pH > 7