JEE Chemistry Hydrogen MCQs Set A

Question:  Following are some properties of hydrogen which of the following properties resemble with alkali metals and which with halogens

(i) Hydrogen lose one electron to form unipositive ions
(ii) Hydrogen gain one electron to form uninegative ions
(iii) Hydrogen forms oxides, halides and sulphides
(iv) Hydrogen has a very high ionization enthalpy
(v) Hydrogen forms a diatomic molecule, combines with elements to form hydrides and covalent compounds.

• a) Alkali metals resemble (i) and (iii)

      Halogens resemble (ii), (iv) and (v)

• b) Alkali metals resemble (i) only

     Halogens resemble (iv) and (v)

• c) Alkali metals resemble (i) and (iii)

     Halogens resemble (ii), (iii) and (v)

• d) Alkali metals resemble (i), (iii) and (iv)

      Halogens resemble (ii) and (v)

Answer: Alkali metals resemble (i) and (iii) 

               Halogens resemble (ii), (iv) and (v)

Question: Hydrogen molecules differs from chlorine molecule in the following respect

• a) Hydrogen molecule cannot participate in coordination bond formation but chlorine molecule can
• b) Hydrogen molecule can form intermolecular hydrogen bonds but chlorine molecule does not
• c) Hydrogen molecule is polar while chlorine molecule is non-polar
• d) Hydrogen molecule is non-polar but chlorine molecule is polar

Answer: Hydrogen molecule cannot participate in coordination bond formation but chlorine molecule can

Question: Hydrogen can behave as a metal

• a) at very high pressure
• b) at very low pressure
• c) at very low temperature
• d) at very high temperature

Answer: at very high pressure

Question: The property of hydrogen which distinguishes it from alkali metals is

• a) its non-metallic character
• b) its reducing character
• c) its affinity for non metal
• d) its electropositive character

Answer:  its non-metallic character

Question: Hydrogen accepts an electron to form inert gas configuration. In this it resembles

• a) halogen
• b) chalcogens
• c) alkali metals
• d) alkaline earth metals

Answer: halogen

Question: Why does H⁺ ion always get associated with other atoms or molecules?

• a) Loss of an electron from hydrogen atom results in a nucleus of very small size as compared to other atoms or ions. Due to small size it cannot exist free
• b) It resembles both alkali metals and halogens
• c) Its reactivity is similar to halogens.
• d) Ionisation enthalpy of hydrogen resembles that of alkali metals

Answer: Loss of an electron from hydrogen atom results in a nucleus of very small size as compared to other atoms or ions. Due to small size it cannot exist free

Question: Which of the following statements is correct ?

• a) It has oxidation number of –1 and +1
• b) It will not be liberated at anode
• c) Hydrogen has same electronegativity as halogens
• d) Hydrogen has same IP as alkali metals

Answer: It has oxidation number of –1 and +1

Question:  Which one of the following is not an isotope of hydrogen ?

• a) Ortho hydrogen
• b) Deuterium
• c) Tritium
• d) None of these

Answer: Ortho hydrogen

Question: Number of neutrons in three isotopes of hydrogen, protium, deuterium and tritium respectively is

• a) 0, 1, 2
• b) 2, 1, 0
• c) 1, 1,1
• d) 2, 0, 1

Answer:  0, 1, 2

Question:

• a) (ii) only
• b) (i) and (ii)
• c) (iii) only
• d) (ii) and (iii)

Answer: (ii) only

Question: Hydrogen bond energy is equal to

• a) 3-10 kcals
• b) 3-7 cals
• c) 30-70 cals
• d) 30-70 kcals

Answer: 3-10 kcals

Question: Which of the following reaction(s) represents commercial method for production of dihydrogen?

• a) (i), (ii) and (iv)
• b) (i), (ii) and (iii)
• c) (iii) only
• d) (ii), (iii) and (iv)

Answer: (i), (ii) and (iv)

Question: Which of the following is formed when zinc reacts with sodium hydroxide?

• a) Both
• b) Sodium zincate
• c) Hydrogen gas
• d) None of these

Answer: Both

Question: Identify x and y in following reaction. What is the mixture of x and y called?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following statements is correct?

• a) Both
• b)

  

• c) Production of syngas from coal is called coal gasification.
• d) None of these

Answer: Both

Question: Why is water gas (mixture of CO and H₂) also called ‘syn gas’?

• a) Because it is used in the synthesis of methanol and a number of hydrocarbons
• b) None of these
• c) Because it is synthesised from methane gas
• d) Because it is synthesised from sewage, saw – dust, scrap wood etc

Answer: Because it is used in the synthesis of methanol and a number of hydrocarbons

Question: Which one of the following pairs of substances on reaction will not evolve H₂ gas?

• a) Copper and HCl (aqueous)
• b) Sodium and ethyl alcohol
• c) Iron and steam
• d) Iron and H₂SO₄ (aqueous)

Answer: Copper and HCl (aqueous)

Question: Which of the following metal evolves hydrogen on reacting with cold dilute HNO₃ ?

• a) Mg
• b) Fe
• c) Al
• d) Cu

Answer: Mg

Question: Hydrogen is evolved by the action of cold dil. HNO₃ on

• a) Mn
• b) Al
• c) Fe
• d) Cu

Answer:  Mn

Question: In Bosch’s process which gas is utilised for the production of hydrogen gas ?

• a) Water gas
• b) None of these
• c) Producer gas
• d) Coal gas

Answer: Water gas

Question: Hydrogen is not obtained when zinc reacts with

• a) Cold water
• b) dil. HCl
• c) Hot NaOH (20%)
• d) dil. H₂SO₄

Answer: Cold water

Question: Which one of the following pairs of substances will not produce hydrogen when reacted together?

• a) Copper and conc. nitric acid
• b) Ethanol and metallic sodium
• c) Magnesium and steam
• d) Phenol and metallic sodium

Answer: Copper and conc. nitric acid

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

• a) Reaction of salts like hydrides with water
• b) Electrolysis of water
• c) Mixing natural hydrocarbons of high molecular weight
• d) Reaction of methane with steam

Answer: Reaction of salts like hydrides with water

Question: Which of the following is formed on reaction of carbon monoxide gas with dihydrogen in presence of cobalt as a catalyst?

• a) Methanol
• b) Formic acid
• c) Methanal
• d) Methane

Answer: Methanol

Question:  Which of the following is not a use of dihydrogen ?

• a) It used in the synthesis of hydroquinone and tartaric acid.
• b) Atomic hydrogen and oxy-hydrogen torches areused for cutting and welding purposes
• c) It used in fuel cells for generating electrical energy
• d) None of these

Answer: It used in the synthesis of hydroquinone and tartaric acid.

Question: Elements of which of the following group do not form hydrides?

• a) Alkaline earth metals
• b) Alkali metals
• c) Halogens
• d) Noble gases

Answer: Alkaline earth metals

Question: Which of the following statements is incorrect?

• a) Melts of ionic hydrides conduct electricity and liberate dihydrogen gas at cathode
• b) Ionic hydrides are crystalline, non-volatile and nonconducting in solid state
• c) Ionic hydrides are stoichiometric compounds of dihydrogen formed with most of s-block elements
• d) All of these

Answer: Melts of ionic hydrides conduct electricity and liberate dihydrogen gas at cathode

Question: Saline hydrides react explosively with water, such fires can be extinguished by

• a) sand
• b) water
• c) carbon dioxide
• d) None of these

Answer: sand

Question:  Choose the correct option for following hydrides. B₂H₆, CH₄, NH₃ and HF

• a)

  

• b)

  

• c) Both
• d) None of these

Answer:

Question:  Elements of which of the following group(s) of periodic table do not form hydrides

• a) Groups 7, 8, 9
• b) Groups 15, 16, 17
• c) Group 13
• d) Group 14

Answer: Groups 7, 8, 9

Question: Which hydride is an ionic hydride ?

• a) NaH
• b) NH₃
• c) H₂S
• d) TiH_1.73

Answer: NaH

Question:  Metal hydride on treatment with water gives

• a) Hydrogen
• b) H₂O
• c) Acid
• d) All of these

Answer: Hydrogen

Question: The polymeric hydride is

• a) MgH₂
• b) NaH
• c) CaH₂
• d) BaH₂

Answer: MgH₂

Question: Ionic hydrides reacts with water to give

• a) basic solutions
• b) acidic solutions
• c) hydride ions
• d) electorns

Answer:  basic solutions

Question: Which of the following in incorrect statement?

• a) d-and f-block elements form ionic hydride
• b) p-block elements form covalent hydride
• c) s-block elements, except Be and Mg, form ionic hydride
• d) None of these

Answer: d-and f-block elements form ionic hydride

Question: Metal hydrides are ionic, covalent or molecular in nature. Among LiH, NaH, KH, RbH, CsH, the correct order of increasing ionic character is

• a) LiH < NaH < KH < RbH < CsH
• b) LiH > NaH > CsH > KH > RbH
• c) RbH > CsH > NaH > KH > LiH
• d) NaH > CsH > RbH > LiH > KH

Answer: LiH < NaH < KH < RbH < CsH

Question: LiAlH₄ is used as

• a) A reducing agent
• b) A water softener
• c) An oxidizing agent
• d) A mordant

Answer: A reducing agent

Question: Water is

• a) more polar than H₂S
• b) more or less identical in polarity with H₂S
• c) less polar than H₂S
• d) None of these

Answer:  more polar than H₂S

Question:

• a) A = Bent, B = 104.5°, C = 95.7 pm
• b) A = Bent, B = 100.5°, C = 95.7 pm
• c) A = Bent, B = 109.5°,C = 99.7 pm
• d) A = Bent, B = 104.5°, C = 99.7 pm

Answer: A = Bent, B = 104.5°, C = 95.7 pm

Question: The H–O–H angle in water molecule is about

• a) 104.5º
• b) 180º
• c) 90º
• d) 102.5°

Answer: 104.5º

Question: Identify the structuer of water in the gaseous phase.

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: The unusual properties of water in the condensed phase (liquid and solid states) are due to the

• a) presence of extensive hydrogen bonding between water molecules
• b) presence of covalent bonding between the water molecules
• c) presence of hydrogen and covalent bonding between the water molecules
• d) presence of ionic bonding

Answer:  presence of extensive hydrogen bonding between water molecules

Question: The boiling point of water is exceptionally high because

• a) water molecules associate due to hydrogen bonding
• b) water molecule is not linear
• c) water molecule is linear
• d) there is covalent bond between H and O

Answer: water molecules associate due to hydrogen bonding

Question: Water possesses a high dielectric constant, therefore

• a) it is a universal solvent
• b) can dissolve covalent compounds
• c) can conduct electricity
• d) it always contains ions

Answer: it is a universal solvent

Question: At its melting point ice is lighter than water because

• a) ice crystals have hollow hexagonal arrangement of H₂O molecules
• b) H₂O molecules are more closely packed in solid state
• c) on melting of ice the H₂O molecule shrinks in size
• d) ice froms mostly heavy water on first melting

Answer: ice crystals have hollow hexagonal arrangement of H₂O molecules

Question: The low density of ice compared to water is due to

• a) hydrogen-bonding interactions
• b) dipole-dipole interactions
• c) dipole-induced dipole interactions
• d) induced dipole-induced dipole interactions

Answer: hydrogen-bonding interactions

Question: When two ice cubes are pressed over each other, they unite to form one cube. Which of the following forces is responsible to hold them together ?

• a) Hydrogen bond formation
• b) Van der Waals forces
• c) Covalent attraction
• d) Ionic interaction

Answer: Hydrogen bond formation

Question: Which of the following reactions is an example of use of water gas in the synthesis of other compounds?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which of the following metals reacts with H₂O at room temp?

• a) Na
• b) Fe
• c) Ag
• d) Al

Answer: Na

Question: Which of the following statements do not define the characteristic property of water “Water is a universal solvent”

• a) It has very low dielectric constant
• b) It can dissolve maximum number of compounds
• c) It has high liquid range
• d) None of these

Answer: It has very low dielectric constant

Question: Which of the following groups of ions makes the water hard?

• a) Magnesium and chloride
• b) Potassium and sulphate
• c) Ammonium and chloride
• d) Sodium and bicarbonate

Answer:  Magnesium and chloride

Question: The process used for the removal of hardness of water is

• a) Calgon
• b) Baeyer
• c) Hoope
• d) Serpeck

Answer: Calgon

Question: When zeolite (hydrated sodium aluminium silicate) is treated with hard water the sodium ions are exchanged with

• a) Ca²⁺ ions
• b) OH^– ions
• c) H⁺ ions
• d) None of these

Answer: Ca²⁺ ions

Question: Calgon used as a water softener is

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Polyphosphates are used as water softening agents because they

• a) forms soluble complexes with cationic species
• b) precipitate cationic species
• c) precipitate anionic species
• d) form soluble complexes with anionic specise

Answer: forms soluble complexes with cationic species

Question: Permanent hardness of water can be removed by adding Calgon (NaPO₃)n. This is an example of

• a) Exchange of ion
• b) None
• c) Adsorption
• d) Precipitation

Answer: Exchange of ion

Question: Which one the following removes temporary hardness of water ?

• a) Slaked lime
• b) Epsom
• c) Plaster of Paris
• d) Hydrolith

Answer: Slaked lime

Question: Permanent hardness of water is due to the presence of

• a) chlorides and sulphates of calcium and magnesium
• b) chlorides and sulphates of sodium and potassium
• c) bicarbonates of sodium and potassium
• d) bicarbonates of calcium and magnesium

Answer: chlorides and sulphates of calcium and magnesium

Question: In lab H₂O₂ is prepared by

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: HCl is added to following oxides. Which one would give H₂O₂

• a) None of these
• b) PbO₂
• c) MnO₂
• d) BaO

Answer: None of these