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Hydrogen — NEET UG Chemistry PYQs

395 previous year questions from Hydrogen with answers and solutions. Numbered list, year tags, and one-tap solutions — built for serious JEE / NEET practice.

395 questionsChemistrySolutions on every page
1

Which of the following statements is NOT true regarding dihydrogen?

MHT CET Medical 2026 Solution View → 2

Which of the following elements belongs to the isotope, tritium?

MHT CET Medical 2026 Solution View → 3

Which of the following mixtures is water gas?

MHT CET Medical 2026 Solution View → 4

Most common isotopes of hydrogen (non-radioactive) is

JIPMER 2019 Solution View → 5

The melting point of solid substances is directly proportional to pressure acting on them. However, ice-melts at a temperature lower than its usual melting point, when the pressure

JIPMER 2016 Solution View → 6

Which of the following atomic and physical properties of hydrogen is false?

JIPMER 2015 Solution View → 7

Point out the correct statement.

JIPMER 2015 Solution View → 8

Number of hydrogen-bonded water molecules associated in CuSO ₄ 5 H ₂ O is

JIPMER 2013 Solution View → 9

Which of the following is the increasing order of enthalpy of vaporization?

JIPMER 2013 Solution View → 10

Hydrogen molecule differs from chlorine molecule in the following respect:

JIPMER 2012 Solution View → 11

Moist hydrogen peroxide can not be dried over conc. H ₂ SO ₄ because

JIPMER 2012 Solution View → 12

Which of the following undergoes reduction with hydrogen peroxide in alkaline medium?

JIPMER 2011 Solution View → 13

Hardness of water is due to presence of salts of :

JIPMER 2006 Solution View → 14

The oxide that gives H ₂ O ₂ on treatment with dilute acid is

JIPMER 2004 Solution View → 15

What is the bond angle in the gas phase for a water molecule?

NEET Solution View → 16

At what temperature does the H 2 O 2 molecule have a dihedral angle of 90.2° in the solid phase?

NEET Solution View → 17

Why is hard water unsuitable for laundry?

NEET Solution View → 18

What is the role of dilute hydrochloric acid in the preparation of dihydrogen?

NEET Solution View → 19

Which halogen reaction with dihydrogen requires a catalyst?

NEET Solution View → 20

What causes the open-type structure with wide holes in ice?

NEET Solution View → 21

What are the primary uses of hydrogen peroxide mentioned in the text?

NEET Solution View → 22

What is the role of barium sulfate in the production of hydrogen peroxide?

NEET Solution View → 23

What is the name of the hydrate formed by hydrogen peroxide when mixed with water?

NEET Solution View → 24

Why is hydrogen peroxide kept away from dust?

NEET Solution View → 25

What is the chemical formula of heavy water?

NEET Solution View → 26

How is peroxodisulphate obtained for the laboratory preparation of hydrogen peroxide?

NEET Solution View → 27

What are the characteristics of ionic hydrides in their solid state?

NEET Solution View → 28

Which of the following molecules is an example of an electron-rich hydride with three lone pairs?

NEET Solution View → 29

What is the product formed when hydrogen peroxide acts as a reducing agent in acidic medium with iodine (I 2 )?

NEET Solution View → 30

What is the chemical formula of sodium hexametaphosphate?

NEET Solution View → 31

What happens to the calcium and magnesium ions in hard water when they react with washing soda?

NEET Solution View → 32

How many protons and electrons does hydrogen have in its atomic form?

NEET Solution View → 33

What type of water association in hydrated salts involves water molecules that are coordinated with the salt ions?

NEET Solution View → 34

What is the industrial process for manufacturing ammonia using dihydrogen and dinitrogen?

NEET Solution View → 35

What happens to the dihedral angle of the H 2 O 2 molecule as it transitions from the gas phase to the solid phase?

NEET Solution View → 36

What is the chemical formula of peroxodisulphate?

NEET Solution View → 37

What role does hydrogen peroxide play in pollution control?

NEET Solution View → 38

Which group of elements forms electron-precise compounds with dihydrogen?

NEET Solution View → 39

What is the current source for the majority (~77%) of industrial dihydrogen production?

NEET Solution View → 40

What is one of the primary advantages of using dihydrogen in fuel cells for generating electrical energy?

NEET Solution View → 41

What is the primary reason for comparing the energy released by combustion of different fuels in terms of mole, mass, and volume?

NEET Solution View → 42

How is zeolite (permutit) regenerated for further use in the ion-exchange method?

NEET Solution View → 43

What is the term for salts that can be crystallized from aqueous solutions as hydrated salts?

NEET Solution View → 44

In which medium does hydrogen peroxide act as an oxidizing agent with manganese (Mn)?

NEET Solution View → 45

Which class of metals is specifically mentioned as reacting with dihydrogen to form hydrides?

NEET Solution View → 46

How can the formation of nitrogen oxides (NO x ) be minimized during the combustion of dihydrogen?

NEET Solution View → 47

What is one of the properties that distinguishes water from other liquids?

NEET Solution View → 48

At what conditions does the formation of ammonia from dihydrogen and dinitrogen take place in the Haber process?

NEET Solution View → 49

Besides dilute hydrochloric acid, what else can be used to prepare dihydrogen according to the paragraph?

NEET Solution View → 50

What is the process called for producing 'syngas' from coal?

NEET Solution View → 51

What is the crystalline form of water?

NEET Solution View → 52

What is the role of hydroxide ions (OH–) in the anion exchange process?

NEET Solution View → 53

What factor largely determines the chemical behavior of dihydrogen and other molecules?

NEET Solution View → 54

Why is the H-H bond dissociation enthalpy of dihydrogen the highest for a single bond between two atoms?

NEET Solution View → 55

With which group of elements does dihydrogen primarily form molecular compounds?

NEET Solution View → 56

What is the commercial meaning of a 30% solution of hydrogen peroxide?

NEET Solution View → 57

What percentage of the human body is composed of water?

NEET Solution View → 58

What is the term used for metals like Pd and Pt that can absorb a significant volume of hydrogen and can be used for hydrogen storage?

NEET Solution View → 59

How is the 1% hydrogen peroxide formed in the industrial process extracted and concentrated?

NEET Solution View → 60

What is the significance of using high current density during the electrolytic oxidation of sulphate solutions to obtain peroxodisulphate?

NEET Solution View → 61

Why is hydrogen peroxide stored in wax-lined glass or plastic vessels in the dark?

NEET Solution View → 62

In what form does hydrogen primarily exist in the earth's crust and the oceans?

NEET Solution View → 63

What is the elemental form of hydrogen?

NEET Solution View → 64

In terms of mass for mass basis, how does the energy release of dihydrogen compare to petrol?

NEET Solution View → 65

What is the dihedral angle?

NEET Solution View → 66

In the manufacture of bulk organic chemicals, particularly methanol, what type of catalyst is used in the reaction of carbon monoxide (CO) with dihydrogen (H 2 )?

NEET Solution View → 67

In the hydrated salt CuSO 4 ·5H 2 O, what does the "5H 2 O" represent?

NEET Solution View → 68

How many isotopes of hydrogen are mentioned in the paragraph?

NEET Solution View → 69

Why is the property of hydrogen absorption on transition metals widely used in catalytic reduction reactions?

NEET Solution View → 70

What is the dihedral angle of the H 2 O 2 molecule in the gas phase?

NEET Solution View → 71

How is the synthetic cation exchange resin (RSO 3 H) converted to RNa for water softening?

NEET Solution View → 72

Which isotope of hydrogen is mentioned to be radioactive?

NEET Solution View → 73

What is the name of the mixture of CO and H 2 produced by the reaction of steam on hydrocarbons or coke at high temperatures?

NEET Solution View → 74

How does hydrogen's ionization enthalpy compare to that of fluorine (F)?

NEET Solution View → 75

What type of compound does hydrogen form with elements?

NEET Solution View → 76

Why are most hydrides formed by d-block and f-block elements almost always non-stoichiometric?

NEET Solution View → 77

What is the advantage of storing and transporting energy in the form of dihydrogen in the Hydrogen Economy?

NEET Solution View → 78

What is the significance of the dihedral angle in molecular geometry?

NEET Solution View → 79

What happens when Calgon (sodium hexametaphosphate) is added to hard water?

NEET Solution View → 80

What can be added as a stabilizer to hydrogen peroxide to prevent its decomposition?

NEET Solution View → 81

What is the primary cause of permanent hardness in water?

NEET Solution View → 82

To which group in the periodic table do alkali metals belong based on their outer electronic configuration?

NEET Solution View → 83

What is the overall reaction for the electrolysis of brine solution?

NEET Solution View → 84

What is the industrial method for preparing hydrogen peroxide?

NEET Solution View → 85

Why does an ice cube float on water?

NEET Solution View → 86

How does the size of H+ compare to normal atomic and ionic sizes?

NEET Solution View → 87

What is the result of treating hard water with washing soda?

NEET Solution View → 88

What is the product formed when hydrogen peroxide acts as a reducing agent in acidic medium with potassium permanganate (KMnO 4 )?

NEET Solution View → 89

What does "100 volume" hydrogen peroxide mean in terms of its oxygen production at STP?

NEET Solution View → 90

What is the term for water that does not contain soluble salts of calcium and magnesium and easily gives lather with soap?

NEET Solution View → 91

Which group of elements is known for forming electron-rich hydrides with excess electrons?

NEET Solution View → 92

What is one of the uses of heavy water in the preparation of other deuterium compounds?

NEET Solution View → 93

How can temporary hardness of water be removed through heating?

NEET Solution View → 94

Under what conditions is atomic hydrogen produced?

NEET Solution View → 95

Which hydride, such as lithium hydride (LiH), is rather unreactive at moderate temperatures with oxygen (O 2 ) or chlorine (Cl 2 )?

NEET Solution View → 96

What is the primary use of heavy water in nuclear reactors?

NEET Solution View → 97

Which metal ion is mentioned as being reduced by dihydrogen in aqueous solution to form the corresponding metal?

NEET Solution View → 98

What happens to hydrogen peroxide when exposed to light, and how is this reaction catalyzed?

NEET Solution View → 99

Where does hydrogen occur in its combined form besides in water?

NEET Solution View → 100

How does washing soda (sodium carbonate) remove permanent hardness from water?

NEET Solution View → 101

In the manufacturing of vanaspati fat, dihydrogen is used to hydrogenate which type of vegetable oils?

NEET Solution View → 102

Why does water have a higher specific heat compared to other liquids?

NEET Solution View → 103

What is the purpose of passing water successively through a cation exchange resin (in the H+ form) and an anion-exchange resin (in the OH– form)?

NEET Solution View → 104

In the equation H 2 + Pd(aq) → Pd(s) + 2H(aq), what does "Pd" represent?

NEET Solution View → 105

What are the two types of hardness of water mentioned in the paragraph?

NEET Solution View → 106

What is the approximate concentration of deuterium in terrestrial hydrogen?

NEET Solution View → 107

Why does hydrogen peroxide have a non-planar structure?

NEET Solution View → 108

How does deuterium differ from protium in terms of neutrons?

NEET Solution View → 109

How is pure hydrogen peroxide obtained in the industrial process after reaching 85% concentration?

NEET Solution View → 110

What happens when an electron is lost from a hydrogen atom?

NEET Solution View → 111

How is hydrogen peroxide stored to prevent its decomposition?

NEET Solution View → 112

Which group of elements does hydrogen resemble in terms of forming oxides, halides, and sulphides?

NEET Solution View → 113

Why is hydrogen considered unique in behavior and best placed separately in the periodic table?

NEET Solution View → 114

What is the role of hydrolysis in the production of hydrogen peroxide from peroxodisulphate?

NEET Solution View → 115

What is the chemical equation for the preparation of dihydrogen using zinc and aqueous alkali mentioned in the paragraph?

NEET Solution View → 116

What reaction causes the formation of scum/precipitate when soap reacts with hard water?

NEET Solution View → 117

In which industrial process is dihydrogen obtained as a byproduct?

NEET Solution View → 118

In the context of hydrogen's use as a fuel, what is the primary advantage of the Hydrogen Economy?

NEET Solution View → 119

Which gas is dihydrogen lighter than?

NEET Solution View → 120

What is the primary use of dihydrogen in the synthesis of ammonia?

NEET Solution View →
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