Question 1: Palette 1/85

JEE Mains 2023 MCQ

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

Assertion A : Isotopes of hydrogen have almost same chemical properties, but difference in their rates of reaction.

Reason R : Isotopes of hydrogen have different enthalpy of bond dissociation.

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

A

A is not correct but R is correct

B

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

C

A is correct but R is not correct

D

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

Question 2: Palette 2/85

JEE Mains 2023 MCQ

Given below are two statements :

Statement I : Permutit process is more efficient compared to the synthetic resin method for the softening of water.

Statement II : Synthetic resin method results in the formation of soluble sodium salts.

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

A

Statement I is correct but Statement II is incorrect

B

Both the Statements I and II are correct

C

Both the Statements I and II are incorrect

D

Statement I is incorrect but Statement II is correct

Question 3: Palette 3/85

JEE Mains 2023 MCQ

Match List I with List II

	LIST I Type of Hydride		LIST II Example
A.	Electron deficient hydride	I.	$\mathrm{MgH_2}$
B.	Electron rich hydride	II.	$\mathrm{HF}$
C.	Electron precise hydride	III.	$\mathrm{B_2H_6}$
D.	Saline hydride	IV.	$\mathrm{CH_4}$

Choose the correct answer from the options given below:

A

A-III, B-II, C-I, D-IV

B

A-II, B-III, C-I, D-IV

C

A-III, B-II, C-IV, D-I

D

A-II, B-III, C-IV, D-I

Question 4: Palette 4/85

JEE Mains 2023 MCQ

Which hydride among the following is less stable?

A

NH$_3$

B

HF

C

LiH

D

BeH$_2$

Question 5: Palette 5/85

JEE Mains 2023 MCQ

Given below are two statements:

Statement-I : Methane and steam passed over a heated $\mathrm{Ni}$ catalyst produces hydrogen gas.

Statement-II : Sodium nitrite reacts with $\mathrm{NH}_{4} \mathrm{Cl}$ to give $\mathrm{H}_{2} \mathrm{O}, \mathrm{N}_{2}$ and $\mathrm{NaCl}$.

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

A

Statement I is correct but Statement II is incorrect

B

Both the statements I and II are incorrect

C

Both the statements I and II are correct

D

Statement I is incorrect but Statement II is correct

Question 6: Palette 6/85

JEE Mains 2023 MCQ

Given below are two statements: one is labelled as Assertion $\mathbf{A}$ and the other is labelled as Reason $\mathbf{R}$

Assertion A : Physical properties of isotopes of hydrogen are different.

Reason R : Mass difference between isotopes of hydrogen is very large.

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

A

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

B

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

C

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

D

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

Question 7: Palette 7/85

JEE Mains 2023 MCQ

Given below are two reactions, involved in the commercial production of dihydrogen (H$_2$). The two reactions are carried out at temperature "T$_1$" and "T$_2$", respectively

$C(s) + {H_2}O(g)\buildrel {{T_1}} \over \longrightarrow CO(g) + {H_2}(g)$

$CO(g) + {H_2}O(g)\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Catalyst}^{{T_2}}} C{O_2}(g) + {H_2}(g)$

The temperatures T$_1$ and T$_2$ are correctly related as :

A

T$_1$ < T$_2$

B

T$_1$ = T$_2$

C

T$_1$ = 100 K, T$_2$ = 1270 K

D

T$_1$ > T$_2$

Question 8: Palette 8/85

JEE Mains 2023 MCQ

Which of the following can reduce decomposition of $\mathrm{H}_{2} \mathrm{O}_{2}$ on exposure to light :

A

Urea

B

Glass containers

C

Alkali

D

Dust

Question 9: Palette 9/85

JEE Mains 2023 MCQ

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

Assertion A : Loss of electron from hydrogen atom results in nucleus of $\sim 1.5 \times 10^{-3} \mathrm{pm}$ size.

Reason R : Proton $\left(\mathrm{H}^{+}\right)$ always exists in combined form.

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

A

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

B

A is correct but R is not correct

C

A is not correct but R is correct

D

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

Question 10: Palette 10/85

JEE Mains 2023 MCQ

The starting material for convenient preparation of deuterated hydrogen peroxide ($\mathrm{D_{2}O_{2}}$) in :

A

$\mathrm{BaO_{2}}$

B

2-ethylanthraquinol

C

$\mathrm{BaO}$

D

$\mathrm{K_{2}S_{2}O_{8}}$

Question 11: Palette 11/85

JEE Mains 2023 MCQ

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

Assertion A : Hydrogen is an environment friendly fuel.

Reason R : Atomic number of hydrogen is 1 and it is a very light element.

In the light of the above statements, choose the correct 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 false but R is true

C

A is true but R is false

D

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

Question 12: Palette 12/85

JEE Mains 2023 MCQ

The normal rain water is slightly acidic and its $\mathrm{pH}$ value is $5.6$ because of which one of the following?

A

$\mathrm{N}_{2} \mathrm{O}_{5}+\mathrm{H}_{2} \mathrm{O} \rightarrow 2 \mathrm{HNO}_{3}$

B

$2 \mathrm{SO}_{2}+\mathrm{O}_{2}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow 2 \mathrm{H}_{2} \mathrm{SO}_{4}$

C

$4 \mathrm{NO}_{2}+\mathrm{O}_{2}+2 \mathrm{H}_{2} \mathrm{O} \rightarrow 4 \mathrm{HNO}_{3}$

D

$\mathrm{CO}_{2}+\mathrm{H}_{2} \mathrm{O} \rightarrow \mathrm{H}_{2} \mathrm{CO}_{3}$

Question 13: Palette 13/85

JEE Mains 2023 MCQ

Given below are two statements :

Statement I : $ \mathrm{H}_{2} \mathrm{O}_{2}$ is used in the synthesis of Cephalosporin

Statement II : $ \mathrm{H}_{2} \mathrm{O}_{2}$ is used for the restoration of aerobic conditions to sewage wastes.

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

A

Statement $\mathbf{I}$ is incorrect but Statement $\mathbf{II}$ is correct

B

Statement $\mathbf{I}$ is correct but Statement $\mathbf{II}$ is incorrect

C

Both Statement $\mathbf{I}$ and Statement $\mathbf{II}$ are incorrect

D

Both Statement $\mathbf{I}$ and Statement $\mathbf{II}$ are correct

Question 14: Palette 14/85

JEE Mains 2023 MCQ

$\mathrm{H}_{2} \mathrm{O}_{2}$ acts as a reducing agent in :

A

$\mathrm{Mn}^{2+}+2 \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \mathrm{MnO}_{2}+2 \mathrm{H}_{2} \mathrm{O}$

B

$2 \mathrm{Fe}^{2+}+2 \mathrm{H}^{+}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow 2 \mathrm{Fe}^{3+}+2 \mathrm{H}_{2} \mathrm{O}$

C

$\mathrm{Na}_{2} \mathrm{S}+4 \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \mathrm{Na}_{2} \mathrm{SO}_{4}+4 \mathrm{H}_{2} \mathrm{O}$

D

$2 \mathrm{NaOCl}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow 2 \mathrm{NaCl}+\mathrm{H}_{2} \mathrm{O}+\mathrm{O}_{2}$

Question 15: Palette 15/85

JEE Mains 2023 MCQ

Which of the given compounds can enhance the efficiency of hydrogen storage tank?

A

SiH$_4$

B

Li/P$_4$

C

NaNi$_5$

D

Di-isobutylaluminium hydride

Question 16: Palette 16/85

JEE Mains 2023 MCQ

Match List I with List II

	List I		List II
A.	Cobalt catalyst	I.	$\mathrm{(H_2+Cl_2)}$ production
B.	Syngas	II.	Water gas production
C.	Nickel catalyst	III.	Coal gasification
D.	Brine solution	IV.	Methanol production

Choose the correct answer from the options given below :

A

A-IV, B-III, C-I, D-II

B

A-IV, B-III, C-II, D-I

C

A-II, B-III, C-IV, D-I

D

A-IV, B-I, C-II, D-III

Question 17: Palette 17/85

JEE Mains 2023 MCQ

In which of the following reactions the hydrogen peroxide acts as a reducing agent?

A

$\mathrm{M{n^{2 + }} + {H_2}{O_2} \to M{n^{4 + }} + 2O{H^ - }}$

B

$\mathrm{HOCl + {H_2}{O_2} \to {H_3}{O^ + } + C{l^ - } + {O_2}}$

C

$\mathrm{PbS + 4{H_2}{O_2} \to PbS{O_4} + 4{H_2}O}$

D

$\mathrm{2F{e^{2 + }} + {H_2}{O_2} \to 2F{e^{3 + }} + 2O{H^ - }}$

Question 18: Palette 18/85

JEE Mains 2022 MCQ

The products obtained during treatment of hard water using Clark's method are :

A

$\mathrm{CaCO}_{3}$ and $\mathrm{MgCO}_{3}$

B

$\mathrm{Ca}(\mathrm{OH})_{2}$ and $\mathrm{Mg}(\mathrm{OH})_{2}$

C

$\mathrm{CaCO}_{3}$ and $\mathrm{Mg}(\mathrm{OH})_{2}$

D

$\mathrm{Ca}(\mathrm{OH})_{2}$ and $\mathrm{MgCO}_{3}$

Question 19: Palette 19/85

JEE Mains 2022 MCQ

The metal salts formed during softening of hardwater using Clark's method are :

A

$\mathrm{Ca}(\mathrm{OH})_{2}$ and $\mathrm{Mg}(\mathrm{OH})_{2}$

B

$\mathrm{CaCO}_{3}$ and $\mathrm{Mg}(\mathrm{OH})_{2}$

C

$\mathrm{Ca}(\mathrm{OH})_{2}$ and $\mathrm{MgCO}_{3}$

D

$\mathrm{CaCO}_{3}$ and $\mathrm{MgCO}_{3}$

Question 20: Palette 20/85

JEE Mains 2022 MCQ

Given below are two statements.

Statement I : Hydrogen peroxide can act as an oxidizing agent in both acidic and basic conditions.

Statement II : Density of hydrogen peroxide at $298 \mathrm{~K}$ is lower than that of $\mathrm{D}_{2} \mathrm{O}$.

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

A

Both Statement I and Statement II are true.

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 21: Palette 21/85

JEE Mains 2022 MCQ

The products obtained from a reaction of hydrogen peroxide and acidified potassium permanganate are :

A

$\mathrm{Mn}^{4+}, \mathrm{H}_{2} \mathrm{O}$ only

B

$\mathrm{Mn}^{2+}, \mathrm{H}_{2} \mathrm{O}$ only

C

$\mathrm{Mn}^{4+}, \mathrm{H}_{2} \mathrm{O}, \mathrm{O}_{2}$ only

D

$\mathrm{Mn}^{2+}, \mathrm{H}_{2} \mathrm{O}, \mathrm{O}_{2}$ only

Question 22: Palette 22/85

JEE Mains 2022 MCQ

Which of the following can be used to prevent the decomposition of $\mathrm{H}_{2} \mathrm{O}_{2}$ ?

A

Urea

B

Formaldehyde

C

Formic acid

D

Ethanol

Question 23: Palette 23/85

JEE Mains 2022 MCQ

High purity (> 99.95%) dihydrogen is obtained by :

A

reaction of zinc with aqueous alkali.

B

electrolysis of acidified water using platinum electrodes.

C

electrolysis of warm aqueous barium hydroxide solution between nickel electrodes.

D

reaction of zinc with dilute acid.

Question 24: Palette 24/85

JEE Mains 2022 MCQ

The reaction of $\mathrm{H}_{2} \mathrm{O}_{2}$ with potassium permanganate in acidic medium leads to the formation of mainly :

A

Mn²⁺

B

Mn⁴⁺

C

Mn³⁺

D

Mn⁶⁺

Question 25: Palette 25/85

JEE Mains 2022 MCQ

Which one of the following reactions indicates the reducing ability of hydrogen peroxide in basic medium?

A

HOCl + H₂O₂ $\to$ H₃O⁺ + Cl^$-$ + O₂

B

PbS + 4H₂O₂ $\to$ PbSO₄ + 4H₂O

C

2MnO$_4^ - $ + 3H₂O₂ $\to$ 2MnO₂ + 3O₂ + 2H₂O + 2OH^$-$

D

Mn²⁺ + H₂O₂ $\to$ Mn⁴⁺ + 2OH^$-$

Question 26: Palette 26/85

JEE Mains 2022 MCQ

Hydrogen has three isotopes : protium (¹H), deuterium (²H or D) and tritium (³H or T). They have nearly same chemical properties but different physical properties. They differ in :

A

number of protons.

B

atomic number.

C

electronic configuration.

D

atomic mass.

Question 27: Palette 27/85

JEE Mains 2022 MCQ

Dihydrogen reacts with CuO to give :

A

CuH₂

B

Cu

C

Cu₂O

D

Cu(OH)₂

Question 28: Palette 28/85

JEE Mains 2022 MCQ

Boiling of hard water is helpful in removing the temporary hardness by converting calcium hydrogen carbonate and magnesium hydrogen carbonate to :

A

CaCO₃ and Mg(OH)₂

B

CaCO₃ and MgCO₃

C

Ca(OH)₂ and MgCO₃

D

Ca(OH)₂ and Mg(OH)₂

Question 29: Palette 29/85

JEE Mains 2022 MCQ

Consider the following reaction:

$2HSO_4^ - (aq)\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{(2)\,Hydrolysis}^{(1)\,Electrolysis}} 2HSO_4^ - + 2{H^ + } + A$

The dihedral angle in product A in its solid phase at 110 K is :

A

104$^\circ$

B

111.5$^\circ$

C

90.2$^\circ$

D

111.0$^\circ$

Question 30: Palette 30/85

JEE Mains 2022 MCQ

The highest industrial consumption of molecular hydrogen is to produce compounds of element :

A

Carbon

B

Nitrogen

C

Oxygen

D

Chlorine

Question 31: Palette 31/85

JEE Mains 2021 MCQ

Hydrogen peroxide reacts with iodine in basic medium to give :

A

IO$_4^ - $

B

IO^$-$

C

I^$-$

D

IO$_3^ - $

Question 32: Palette 32/85

JEE Mains 2021 MCQ

Which one of the following statements is incorrect?

A

Atomic hydrogen is produced when H₂ molecules at a high temperature are irradiated with UV radiation.

B

At around 2000 K, the dissociation of dihydrogen into its atoms is nearly 8.1%

C

Bond dissociation enthalpy of H₂ is highest among diatomic gaseous molecules which contain a single bond.

D

Dihydrogen is produced on reacting zinc with HCl as well as NaOH_(aq).

Question 33: Palette 33/85

JEE Mains 2021 MCQ

Given below are two statements :

Statement I : The process of producing syn-gas is called gasification of coal.

Statement II : The composition of syn-gas is CO + CO₂ + H₂ (1 : 1 : 1)

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 false

D

Both Statement I and Statement II are true

Question 34: Palette 34/85

JEE Mains 2021 MCQ

The oxide that gives H₂O₂ most readily on treatment with H₂O is :

A

PbO₂

B

Na₂O₂

C

SnO₂

D

BaO₂ . 8H₂O

Question 35: Palette 35/85

JEE Mains 2021 MCQ

Deuterium resembles hydrogen in properties but :

A

reacts slower than hydrogen

B

reacts vigorously than hydrogen

C

reacts just as hydrogen

D

emits $\beta$⁺ particles

Question 36: Palette 36/85

JEE Mains 2021 MCQ

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

Assertion (A) : Heavy water is used for the study of reaction mechanism.

Reason (R) : The rate of reaction for the cleavage of O - H bond is slower than that of O - D bond.

Choose the most appropriate answer from the options given below :

A

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

B

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

C

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

D

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

Question 37: Palette 37/85

JEE Mains 2021 MCQ

Which one of the following methods is most suitable for preparing deionized water?

A

Synthetic resin method

B

Clark's method

C

Calgon's method

D

Permutit method

Question 38: Palette 38/85

JEE Mains 2021 MCQ

The number of neutrons and electrons, respectively, present in the radioactive isotope of hydrogen is :

A

1 and 1

B

3 and 1

C

2 and 1

D

2 and 2

Question 39: Palette 39/85

JEE Mains 2021 MCQ

At 298.2 K the relationship between enthalpy of bond dissociation (in kJ mol^$-$1) for hydrogen (E_H) and its isotope, deuterium (E_D), is best described by :

A

${E_H} = {1 \over 2}{E_D}$

B

${E_H} = {E_D}$

C

${E_H} \simeq {E_D} - 7.5$

D

${E_H} = 2{E_D}$

Question 40: Palette 40/85

JEE Mains 2021 MCQ

The water having more dissolved O₂ is :

A

boiling water

B

water at 80$^\circ$C

C

polluted water

D

water at 4$^\circ$C

Question 41: Palette 41/85

JEE Mains 2021 MCQ

The single largest industrial application of dihydrogen is :

A

Manufacture of metal hybrides

B

Rocket fuel in space research

C

In the synthesis of ammonia

D

In the synthesis of nitric acid

Question 42: Palette 42/85

JEE Mains 2021 MCQ

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

Assertion A : The dihedral angles in H₂O₂ in gaseous phase is 90.2$^\circ$ and in solid phase is 111.5$^\circ$.

Reason R : The change in dihedral angle in solid and gaseous phase is due to the difference in the intermolecular forces.

Choose the most appropriate answer from the options given below for A and R.

A

A is correct but R is not correct.

B

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

C

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

D

A is not correct but R is correct.

Question 43: Palette 43/85

JEE Mains 2021 MCQ

In basic medium, H₂O₂ exhibits which of the following reactions?

(A) Mn²⁺ $ \to $ Mn⁴⁺

(B) I² $ \to $ I^$-$

(C) PbS $ \to $ PbSO₄

Choose the most appropriate answer from the options given below :

A

(B) only

B

(A), (B) only

C

(A) only

D

(A), (C) only

Question 44: Palette 44/85

JEE Mains 2021 MCQ

The functional groups that are responsible for the ion-exchange property of cation and anion exchange resins, respectively, are :

A

$-$SO₃H and $-$NH₂

B

$-$NH₂ and COOH

C

$-$NH₂ and $-$SO₃H

D

$-$SO₃H and $-$COOH

Question 45: Palette 45/85

JEE Mains 2021 MCQ

The INCORRECT statement(s) about heavy water is (are)

(A) used as a moderator in nuclear reactor

(B) obtained as a by-product in fertilizer industry

(C) used for the study of reaction mechanism

(D) has a higher dielectric constant than water

Choose the correct answer from the options given below :

A

(D) only

B

(B) and (D) only

C

(B) only

D

(C) only

Question 46: Palette 46/85

JEE Mains 2021 MCQ

The correct statements about H₂O₂ are :

(A) used in the treatment of effluents.

(B) used as both oxidising and reducing agents.

(C) the two hydroxyl groups lie in the same plane.

(D) miscible with water.

Choose the correct answer from the options given below :

A

(A), (C) and (D) only

B

(A), (B), (C) and (D)

C

(A), (B) and (D) only

D

(B), (C) and (D) only

Question 47: Palette 47/85

JEE Mains 2021 MCQ

Given below are two statements :

Statement I : H₂O₂ can act as both oxidising and reducing agent in basic medium.

Statement II : In the hydrogen economy, the energy is transmitted in the form of dihydrogen.

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

Statement I is false but statement II is true

C

Statement I is true but statement II is false

D

Both statement I and statement II are true

Question 48: Palette 48/85

JEE Mains 2021 MCQ

Statements about heavy water are given below :

A. Heavy water is used in exchange reactions for the study of reaction mechanisms.

B. Heavy water is prepared by exhaustive electrolysis of water.

(C) Heavy water has higher boiling point than ordinary water.

(D) Viscosity of H₂O is greater than D₂O.

Choose the most appropriate answer from the options given below :

A

A, B, and C only

B

A and C only

C

A and D only

D

A and B only

Question 49: Palette 49/85

JEE Mains 2021 MCQ

Water does not produce CO on reacting with :

A

C

B

CH₄

C

C₃H₈

D

CO₂

Question 50: Palette 50/85

JEE Mains 2021 MCQ

Which of the following equation depicts the oxidizing nature of H₂O₂?

A

$C{l_2} + {H_2}{O_2} \to 2HCl + {O_2}$

B

$KI{O_4} + {H_2}{O_2} \to KI{O_3} + {H_2}O + {O_2}$

C

$2{I^ - } + {H_2}{O_2} + 2{H^ + } \to {I_2} + 2{H_2}O$

D

${I_2} + {H_2}{O_2} + 2O{H^ - } \to 2{I^ - } + 2{H_2}O + {O_2}$

Question 51: Palette 51/85

JEE Mains 2021 MCQ

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

Assertion A : Hydrogen is the most abundant element in the Universe, but it is not the most abundant gas in the troposphere.

Reason R : Hydrogen is the lightest element.

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

A

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

B

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

C

A is true but R is false

D

A is false but R is true.

Question 52: Palette 52/85

JEE Mains 2021 MCQ

(A) HOCI + H₂O₂ → H₃O⁺ + Cl^- + O₂

(B) I₂ + H₂O₂ + 2OH^- → 2I^- + 2H₂O + O₂

Choose the correct option.

A

H₂O₂ acts as reducing and oxidising agent respectively in equations (A) and (B).

B

H₂O₂ act as oxidizing and reducing agent respectively in equations (A) and (B).

C

H₂O₂ acts as oxidising agent in equations (A) and (B).

D

H₂O₂ acts as reducing agent in equations (A) and (B).

Question 53: Palette 53/85

JEE Mains 2020 MCQ

Dihydrogen of high purity (> 99.95%) is obtained through :

A

the electrolysis of acidified water using Pt electrodes

B

the electrolysis of warm Ba(OH)₂ solution using Ni electrodes

C

the electrolysis of brine solution

D

the reaction of Zn with dilute HCl

Question 54: Palette 54/85

JEE Mains 2020 MCQ

The one that is NOT suitable for the removal of permanent hardness of water is :

A

Ion-exchange method

B

Calgon's method

C

Treatment with sodium carbonate

D

Clark's method

Question 55: Palette 55/85

JEE Mains 2020 MCQ

Hydrogen peroxide, in the pure state, is :

A

Linear and blue in color

B

Linear and almost colorless

C

Non-planar and almost colorless

D

Planar and bluein color

Question 56: Palette 56/85

JEE Mains 2020 MCQ

The equation that represents the water-gas shift reaction is :

A

CO(g) + H₂O(g) $\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Catalyst}^{673K}} $ CO₂(g) + H₂(g)

B

CH₄(g) + H₂O(g) $\mathrel{\mathop{\kern0pt\longrightarrow} \limits_{Ni}^{1270K}} $ CO(g) + 3H₂(g)

C

C(s) + H₂O(g) $\buildrel {1270K} \over \longrightarrow $ CO(g) + H₂(g)

D

2C(s) + O₂(g) + 4N₂(g) $\buildrel {1273K} \over \longrightarrow $ 2CO(g) + 4N₂(g)

Question 57: Palette 57/85

JEE Mains 2020 MCQ

If the boiling point of H₂O is 373 K, the boiling point of H₂S will be :

A

greater than 300 K but less than 373 K

B

equal to 373 K

C

more than 373 K

D

less than 300 K

Question 58: Palette 58/85

JEE Mains 2020 MCQ

Amongst the following, the form of water with the lowest ionic conductance at 298 K is :

A

saline water used for intravenous injection

B

sea water

C

distilled water

D

water from a well

Question 59: Palette 59/85

JEE Mains 2020 MCQ

Among the statements (a) - (d), the correct ones are :
(a) Decomposition of hydrogen peroxide gives dioxygen.
(b) Like hydrogen peroxide, compounds, such as KCIO₃, Pb(NO₃)₂ and NaNO₃ when heated liberate dioxygen.
(c) 2-Ethylanthraquinone is useful for the industrial preparation of hydrogen peroxide.
(d) Hydrogen peroxide is used for the manufacture of sodium perborate.

A

(a), (b), (c) and (d)

B

(a) and (c) only

C

(a), (b) and (c) only

D

(a), (c) and (d) only

Question 60: Palette 60/85

JEE Mains 2020 MCQ

In comparison to the zeolite process for the removal of permanent hardness, the synthetic resins method is :

A

less efficient as the resins cannot be regenerated.

B

more efficient as it can exchange only cations.

C

more efficient as it can exchange both cations as well as anions.

D

less efficient as it exchanges only anions.

Question 61: Palette 61/85

JEE Mains 2019 MCQ

The temporary hardness of a water sample is due to compound X. Boiling this sample converts X to compound Y. X and Y, respectively, are :

A

Mg(HCO₃)₂ and MgCO₃

B

Ca(HO₃)₂ and CaO

C

Ca(HCO₃)₂ and Ca(OH)₂

D

Mg(HCO₃)₂ and Mg(OH)₂

Question 62: Palette 62/85

JEE Mains 2019 MCQ

The metal that gives hydrogen gas upon treatment with both acid as well as base is :

A

mercury

B

zinc

C

iron

D

magnesium

Question 63: Palette 63/85

JEE Mains 2019 MCQ

The correct statements among (a) to (d) are :
(a) saline hydrides produce H₂ gas when reacted with H₂O.
(b) reaction of LiAlH₄ with BF₃ leads to B₂H₆.
(c) PH₃ and CH₄ are electron - rich and electron - precise hydrides, respectively.
(d) HF and CH₄ are called as molecular

A

(a), (b), (c) and (d)

B

(a), (c) and (d) only

C

(c) and (d) only

D

(a), (b) and (c) only

Question 64: Palette 64/85

JEE Mains 2019 MCQ

The synonym for water gas when used in the production of methanol is :

A

fuel gas

B

laughing gas

C

syn gas

D

natural gas

Question 65: Palette 65/85

JEE Mains 2019 MCQ

The number of water molecule(s) not coordinated to copper ion directly in CuSO₄.5H₂O, is :

A

2

B

4

C

3

D

1

Question 66: Palette 66/85

JEE Mains 2019 MCQ

The strength of 11.2 volume solution of H₂O₂ is : [Given that molar mass of H = 1 g mol–1 and O = 16 g mol^–1]

A

3.4%

B

34%

C

13.6%

D

1.7%

Question 67: Palette 67/85

JEE Mains 2019 MCQ

100 mL of a water sample contains 0.81 g of calcium bicrabonate and 0.73 g of magnesium bicarbonate. The hardness of this water sample expressed in terms of equivalents of CaCO₃ is : (Molar mass of calcium bicarbonate is 162 g mol^–1 and magnesium bicarbonate is 146 g mol^–1)

A

1,000 ppm

B

100 ppm

C

10,000 ppm

D

5,000 ppm

Question 68: Palette 68/85

JEE Mains 2019 MCQ

The volume strength of 1M H₂O₂ is : (Molar mass of H₂O₂ = 34 g mol^–1)

A

5.6

B

22.4

C

11.35

D

16.8

Question 69: Palette 69/85

JEE Mains 2019 MCQ

NaH is an example of :

A

metallic hydride

B

saline hydride

C

electron-rich hydrid

D

molecular hydride

Question 70: Palette 70/85

JEE Mains 2019 MCQ

The correct statements among (a) to (d) regarding H₂ as a fuel are :

(a)   It produces less pollutants than petrol.

(b)   A cylinder of compressed dihydrogen weighs $ \sim $ 30 times more than a petrol tank producing the same amount of energy.

(c)   Dihydrogen is stored in tanks of metal alloys like NaNi₅.

(d)   On combustion, values of energy released per gram of liquid dihydrogen and LPG are 50 and 142 KJ, respectively.

A

(a) and (c) only

B

(b) and (d) only

C

(a), (b) and (c) only

D

(b), (c) and (d) only

Question 71: Palette 71/85

JEE Mains 2019 MCQ

The chemical nature of hydrogen peroxide is :

A

Oxidising agent in acidic medium, but not in basic medium

B

Oxidising and reducing agent in both acidic and basic medium

C

Reducing agent in basic medium, but not in acidic medium

D

Oxidising and reducing agent in acidic medium, but not in basic medium.

Question 72: Palette 72/85

JEE Mains 2019 MCQ

The total number of isotopes of hydrogen and number of radioactive isotopes among them, respectively, are :

A

3 and 2

B

2 and 1

C

2 and 0

D

3 and 1

Question 73: Palette 73/85

JEE Mains 2019 MCQ

The temporary hardness of water is due to :

A

Na₂SO₄

B

NaCl

C

Ca(HCO₃)₂

D

CaCl₂

Question 74: Palette 74/85

JEE Mains 2019 MCQ

The isotopes of hydrogen are :

A

Tritium and protium only

B

Protium and Deuterium only

C

Protium, deuterium and tritium

D

Deuterium and tritium only

Question 75: Palette 75/85

JEE Mains 2018 MCQ

Hydrogen peroxide oxidises [Fe(CN)₆]^4- to [Fe(CN)₆]^3- in acidic medium but reduces [Fe(CN)₆]^3- to [Fe(CN)₆]^4- in alkaline medium. The other products formed are, respectively :

A

H₂O and (H₂O + OH^-)

B

(H₂O + O₂) and H₂O

C

(H₂O + O₂) and (H₂O + OH^-)

D

H₂O and (H₂O + O₂)

Question 76: Palette 76/85

JEE Mains 2017 MCQ

In which of the following reactions, hydrogen peroxide acts as an oxidizing agent ?

A

HOCl + H₂O₂ $ \to $ H₃O⁺ + Cl^$-$ + O₂

B

I₂ + H₂O₂ + 2OH^$-$ $ \to $ 2I^$-$ + 2H₂O + O₂

C

2Mn$O_4^ - $ + 3H₂O₂ $ \to $ 2 MnO₂ + 3O₂ + 2H₂O + 2OH^$-$

D

PbS + 4H₂O₂ $ \to $ PbSO₄ + 4H₂O

Question 77: Palette 77/85

JEE Mains 2016 MCQ

Identify the reaction which does not liberate hydrogen :

A

Reaction of zinc with aqueous alkali.

B

Electrolysis of acidified water using Pt electrodes.

C

Allowing a solution of sodium in liquid ammonia to stand.

D

Reaction of lithium hydride with B₂H₆.

Question 78: Palette 78/85

JEE Mains 2016 MCQ

Identify the incorrect statement regarding heavy water :

A

It reacts with Al₄C₃ to produce CD₄ and Al(OD)₃ .

B

It is used as a coolant in nuclear reactors.

C

It reacts with CaC₂ to produce C₂D₂ and Ca(OD)₂ .

D

It reacts with SO₃ to form deuterated sulphuric acid (D₂SO₄).

Question 79: Palette 79/85

JEE Mains 2016 MCQ

Which one of the following statements about water is FALSE?

A

Water is oxidized to oxygen during photosynthesis

B

Water can act both as an acid and as a base.

C

There is extensive intramolecular hydrogen bonding in the condensed phase.

D

Ice formed by heavy water sinks in normal water

Question 80: Palette 80/85

JEE Mains 2015 MCQ

From the following statements regarding H₂O₂, choose the incorrect statement :

A

It decomposes on exposure to light

B

It has to be stored in plastic or wax lined glass bottles in dark

C

It has to be kept away from dust

D

It can act only as an oxidizing agent

Question 81: Palette 81/85

JEE Mains 2012 MCQ

Very pure hydrogen (99.9%) can be made by which of the following processes?

A

Reaction of methane with steam

B

Mixing natural hydrocarbons of high molecular weight

C

Electrolysis of water

D

Reaction of salt like hydrides with water

Question 82: Palette 82/85

JEE Mains 2008 MCQ

In context with the industrial preparation of hydrogen from water gas (CO + H₂), which of the following is the correct statement?

A

CO and H₂ are fractionally separated using differences in their densities

B

CO is removed by absorption in aqueous Cu₂Cl₂ solution

C

H₂ is removed through occlusion with Pd

D

CO is oxidised to CO₂ with steam in the presence of a catalyst followed by absorption of CO₂ in alkali

Question 83: Palette 83/85

JEE Mains 2005 MCQ

Which of the following statements in relation to the hydrogen atom is correct?

A

3s orbital is lower in energy than 3p orbital

B

3p orbital is lower in energy than 3d orbital

C

3s and 3p orbitals are of lower energy than 3d orbital

D

3s, 3p and 3d orbitals all have the same energy

Question 84: Palette 84/85

JEE Mains 2003 MCQ

Which one of the following process will produce hard water?

A

Saturation of water with MgCO₃

B

Saturation of water with CaSO₄

C

Addition of Na₂SO₄ to water

D

Saturation of water with CaCO₃

Question 85: Palette 85/85

JEE Mains 2003 MCQ

Which of the following could act as a propellant for rockets?

A

Liquid oxygen + liquid argon

B

Liquid hydrogen + liquid oxygen

C

Liquid nitrogen + liquid oxygen

D

Liquid hydrogen + liquid nitrogen