JEE Chemistry The P Block Elements MCQs Set A

Question: The non-metal oxides are ____x____ whereas metal oxides are ___y ____ in nature.

• a) x = acidic or neutral, y = basic
• b) x = acidic, y = neutral
• c) x = basic, y = acidic
• d) x = neutral, y = basic

Answer: x = acidic or neutral, y = basic

Question: Which of the following is most abundant in the earth crust ?

• a) Aluminium
• b) Thallium
• c) Boron
• d) Gallium

Answer: Aluminium

Question:

• a) B > Al < Ga > In < Tl
• b) B < Al < Ga < In < Tl
• c) B > Al > Ga > In > Tl
• d) B < Al > Ga < In > Tl

Answer: B > Al < Ga > In < Tl

Question:  The relationship between first, second and third ionisation enthalpies of each group-13 element is

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: Which of the following properties of aluminium makes it useful for food packaging ?

• a) Low density
• b) Non toxicity
• c) Good thermal conductivity
• d) Good electrical conductivity

Answer: Low density

Question: Which of the following is/are true regarding gallium?

(i) It has unusually low melting point (303 K).
(ii) It exist in liquid state during summer.
(iii) It has a high boiling point (2676 K).
The correct option is

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

Answer: (i), (ii) and (iii)

Question: The element which shows least metallic character is

• a) Boron
• b) Indium
• c) None of these
• d) Gallium

Answer: Boron

Question: Which one of the following has the lowest m.p.?

• a) Ga
• b) B
• c) Al
• d) Tl

Answer: Ga

Question: Which of the following does not form M³⁺ ion?

• a) Boron
• b) Aluminium
• c) Gallium
• d) Indium

Answer: Boron

Question: The group 13 element that is liquid during summer and used for measuring high temperature is

• a) Gallium
• b) Boron
• c) Aluminium
• d) Indium

Answer: Gallium

Question: Thallium shows different oxidation states because

• a) of inert pair effect
• b) it is transition element
• c) of its amphoteric character
• d) of its higher reactivity

Answer: of inert pair effect

Question: The exhibition of highest co-ordination number depends on the availability of vacant orbitals in the central atom. Which of the following elements is not likely to act as central atom in

• a) B
• b) Ga
• c) Al
• d) In

Answer: B

Question: Which out of the following compounds does not exist?

• a) TlCl₅
• b) BF₃
• c) TlCl₃
• d) None of these

Answer: TlCl₅

Question:  Aluminium chloride is a/an

• a) Lewis acid
• b) Bronsted - Lowery acid
• c) Arhenius acid
• d) Lewis base

Answer: Lewis acid

Question: The strongest Lewis acid is

• a) BI₃
• b) BCl₃
• c) BF₃
• d) BBr₃

Answer: BI₃

Question: AlCl₃ on hydrolysis gives

• a) Al(OH)₃
• b) AlCl₃.6H₂O
• c) Al₂O₃. H₂O
• d) None of these

Answer: Al(OH)₃

Question: Which metal is protected by a layer of its own oxide?

• a) Al
• b) Au
• c) Ag
• d) Fe

Answer: Al

Question: Aluminium vessels should not be washed with materials containing washing soda because

• a) washing soda reacts with aluminium to form soluble aluminate
• b) washing soda reacts with aluminium to form insoluble aluminium oxide
• c) washing soda is easily decomposed
• d) washing soda is expensive

Answer: washing soda reacts with aluminium to form soluble aluminate

Question: When Al is added to KOH solution

• a) hydrogen is evolved
• b) oxygen is evolved
• c) no action takes place
• d) water is produced

Answer: hydrogen is evolved

Question: Which of the following does not react with aqueous NaOH ?

• a) B
• b) Ga
• c) Al
• d) Tl

Answer: B

More Questions................................................

Question: Amphoteric oxide among the following is

• a) Ga₂O₃
• b) Tl₂O₃
• c) B₂O₃
• d) In₂O₃

Answer: Ga₂O₃

Question: Boron forms covalent compound due to

• a) Both
• b) small size
• c) higher ionization energy
• d) None of these

Answer: Both

Question: NH₃ and BF₃ form an adduct readily because they form

• a) a coordinate bond
• b) an ionic bond
• c) a hydrogen bond
• d) a covalent bond

Answer: a coordinate bond

Question: The factor responsible for weak acidic nature of B–F bonds in BF₃ is

• a) Tetra-borate
• b) Meta-borate
• c) Ortho-borate
• d) Double oxide

Answer: Tetra-borate

Question: In borax bead test which compound is formed?

• a) Meta-borate
• b) Tetra-borate
• c) Ortho-borate
• d) Double oxide

Answer: Meta-borate

Question: The formula of mineral borax is

• a) Na₂B₄O₇ .10H₂O
• b) Na₂B₄O₇.4H₂O
• c) Na₂B₄O₇
• d) None of these

Answer: Na₂B₄O₇ .10H₂O

Question: Which of the following hydroxide is acidic ?

• a) B(OH)₃
• b) Ca(OH)₃
• c) Al(OH)₃
• d) Tl(OH)₃

Answer: B(OH)₃

Question: Orthoboric acid

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: H₃BO₃ on heating up to 373 K yields:

• a) metaboric acid
• b) tetraboric acid
• c) boric anhydride
• d) orthoboric acid

Answer: tetraboric acid

Question: Boric acid is polymeric due to

• a) the presence of hydrogen bonds
• b) its acidic nature
• c) its monobasic nature
• d) its geometry

Answer: the presence of hydrogen bonds

Question: B(OH)₃ is

• a) monobasic acid
• b) tribasic acid
• c) dibasic acid
• d) triacidic base

Answer: monobasic acid

Question: Orthoboric acid when heated to red hot gives

• a) pyroboric acid
• b) boric anhydride
• c) metaboric acid
• d) boron and water

Answer: pyroboric acid

Question: Which is false in case of boric acid H₃BO₃?

• a) It acts as a tribasic acid.
• b) It has a planar structure
• c) It acts as a monobasic acid
• d) It is soluble in hot water

Answer: It acts as a tribasic acid.

Question: BCl₃ does not exist as dimer but BH3 exists as dimer (B₂H₆) because

• a) large sized chlorine atoms do not fit in between the small boron atoms where as small sized hydrogen atoms get fitted in between boron atoms
• b) None of the above
• c) chlorine is more electronegative than hydrogen
• d) None of these

Answer: large sized chlorine atoms do not fit in between the small boron atoms where as small sized hydrogen atoms get fitted in between boron atoms

Question:

• a) B₂H₆
• b) B₃H₈
• c) B₄H₁₀
• d) BH₃

Answer: B₂H₆

Question: Inorganic benzene is

• a) B₃H₆N₃
• b) H₃B₃N₆
• c) Both
• d) None of these

Answer: B₃H₆N₃

Question: The structure of diborane ( B₂H₆ ) contains

• a) four 2c-2e bonds and two 3c-2e bonds
• b) two 2c-2e bonds and four 3c-2e bonds
• c) two 2c-2e bonds and two 3c-3e bonds
• d) four 2c-2e bonds and four 3c-2e bonds

Answer: four 2c-2e bonds and two 3c-2e bonds

Question: In diborane

• a) 2– bridged hydrogens and four terminal hydrogens are present
• b) 3–bridged and three terminal hydrogens are present
• c) None of these
• d) 4–bridged hydrogens and two terminal hydrogens are present

Answer: 2– bridged hydrogens and four terminal hydrogens are present

Question: Diborane upon hydrolysis gives

• a) orthoboric acid
• b) boric anhydride
• c) metaboric acid
• d) boron oxide

Answer: orthoboric acid

Question: Borazole is known as

• a) inorganic benzene
• b) organic benzene
• c) organic xylene
• d) inorganic xylene

Answer: inorganic benzene

Question: The compounds of boron and hydrogen are collectively called

• a) boranes
• b) borazoles
• c) diboranes
• d) boracits

Answer: boranes

Question:  The bonds present in borazole or inorganic benzene are

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The two type of bonds present in B₂H₆ are covalent and

• a) hydrogen bridge bond
• b) ionic
• c) co-ordinate
• d) None of these

Answer: hydrogen bridge bond

Question: Reaction of diborane with ammonia gives initially

• a)

  

• b)

  

• c)

  

• d) Borazole

Answer:

Question: Which of the following compounds is not matched correctly with its structure?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: The electronic configuration of four different elements is given below. Identify the group 14 element among these

• a) [Ne] 3s²3p²
• b) [He] 2s¹
• c) [Ne] 3s²
• d) None of these

Answer: [Ne] 3s²3p²

Question: Which of the following is most electronegative?

• a) C
• b) Pb
• c) Si
• d) Sn

Answer:  C

Question: Which of the following isotope of carbon is radioactive?

• a) 14_C
• b) 12_C
• c) 13_C
• d) All of these

Answer: 14_C

Question: Carbon and silicon belong to group 14. The maximum coordination number of carbon in commonly occurring compounds is 4, whereas that of silicon is 6. This is due to

• a) availability of d-orbitals in silicon
• b) more electropositive nature of silicon
• c) large size of silicon
• d) None of these

Answer: availability of d-orbitals in silicon

Question: The inert pair effect is most prominent in

• a) Pb
• b) Si
• c) C
• d) Ge

Answer: Pb

Question: The most stable +2 oxidation state is exhibited by

• a) Pb
• b) Fe
• c) Sn
• d) Si

Answer:  Pb

Question: Which of the following lead oxides is present in ‘Sindhur’?

• a) Pb₃O₄
• b) PbO₂
• c) PbO
• d) None of these

Answer: Pb₃O₄

Question: Mark the oxide which is amphoteric in character

• a) SnO₂
• b) CO₂
• c) SiO₂
• d) CaO

Answer: SnO₂

Question: Red lead is

• a) Pb₃O₄
• b) Pb₂O₃
• c) PbO
• d) None of these

Answer: Pb₃O₄

Question: The oxide of lead used in lead accumulators is

• a) PbO₂
• b) Pb₂O₃
• c) PbO
• d) None o these

Answer: PbO₂

Question:

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

Answer: (iv) only

Question: Least thermally stable is

• a) GeBr₄
• b) SiCl₄
• c) CCl₄
• d) GeCl₄

Answer: GeBr₄

Question: Unlike the other elements of its group carbon and silicon does not form MX₂ type molecules because

• a) energetically this is not possible
• b) carbon undergoes catenation
• c) it is non-metallic
• d) carbon does not contain d-orbital

Answer: energetically this is not possible

Question: Which of the following halides is the most stable?

• a) CF₄
• b) CBr₄
• c) CI₄
• d) CCl₄

Answer: CF₄

Question: The stability of dihalides of Si, Ge, Sn and Pb increases steadily in the sequence

• a) SiX₂ << GeX₂ << SnX₂ << PbX₂
• b) SiX₂ << GeX₂ << PbX₂ << SnX₂
• c) GeX₂ << SiX₂ << SnX₂ << PbX₂
• d) None of these

Answer: SiX₂ << GeX₂ << SnX₂ << PbX₂

Question: When ammonia is heated with cupric oxide, a molecule of ammonia will

• a) lose 3 electrons
• b) lose 2 electrons
• c) gain 3 electrons
• d) gain 2 electrons

Answer: lose 3 electrons

Question: In which the NH₃ is not used ?

• a) Anaesthetic
• b) Cold storage
• c) Manufacture of rayon and plastic
• d) None of these

Answer: Anaesthetic

Question: Liquid ammonia bottles are opened after cooling them in ice for sometime. It is because liquid NH₃

• a) Has a high vapour pressure
• b) Brings tears to the eyes
• c) Is a corrosive liquid
• d) Is a mild explosive

Answer: Has a high vapour pressure

Question: Ammonia is generally manufactured for fertilizers by the reaction

• a) By passing a mixture of N₂ and H₂ under high pressure and moderate temperature over a catalyst
• b)

  

• c) None of these
• d) By passing an electric discharge in a mixture of N₂ and H₂

Answer: By passing a mixture of N₂ and H₂ under high pressure and moderate temperature over a catalyst

Question: Nitrogen dioxide cannot be obtained by heating

• a) KNO₃
• b) Pb(NO₃)₂
• c) AgNO₃
• d) None of these

Answer: KNO₃

Question: The bonds present in N₂O₅ are

• a) covalent and coordinate
• b) covalent and ionic
• c) only ionic
• d) only covalent

Answer: covalent and coordinate

Question: Which of the following oxides of nitrogen is a coloured gas?

• a) NO₂
• b) NO
• c) N₂O
• d) None of these

Answer: NO₂

Question: Which of the following oxides is neutral ?

• a) N₂O
• b) N₂O₄
• c) N₂O₃
• d) N₂O₅

Answer: N₂O

Question:  Which of the following shows nitrogen with its increasing order of oxidation number?

• a)

  

• b)

  

• c) Both
• d) None of these

Answer:

Question: In which one of the following oxides of nitrogen, one nitrogen atom is not directly linked to oxygen?

• a) N₂O
• b) NO
• c) N₂O₄
• d) N₂O₃

Answer: N₂O

Question: Which of the following oxides of nitrogen reacts with FeSO₄ to form a dark brown compound

• a) NO
• b) N₂O₃
• c) N₂O
• d) NO₂

Answer:  NO

Question: Which oxide of nitrogen is obtained on heating ammonium nitrate at 250ºC ?

• a) Nitrous oxide
• b) Dinitrogen tetraoxide
• c) Nitric oxide
• d) Nitrogen dioxide

Answer: Nitrous oxide

Question: Which of the following can be used as an anaesthesia

• a) N₂O
• b) NCl₃
• c) NO
• d) NO₂

Answer: N₂O

Question: A deep brown gas is formed by mixing two colourless gases which are

• a) NO and O₂
• b) NO₂ and O₂
• c) N₂O and NO
• d) None of these

Answer: NO and O₂

Question: Which of the following elements does not form stable diatomic molecules ?

• a) Phosphorus
• b) Oxygen
• c) Iodine
• d) Nitrogen

Answer: Phosphorus

Question: The catalyst used in the manufacture of HNO₃ by Ostwald’s process is

• a) platinum gauze
• b) finely divided nickel
• c) vanadium pentoxide
• d) platinum black

Answer: platinum gauze

Question: Concentrated nitric acid, upon long standing, turns yellow brown due to the formation of

• a) NO₂
• b) N₂O₄
• c) NO
• d) N₂O

Answer: NO₂

Question: Which of the following trihalide is unstable?

• a) NCl₃
• b) AsCl₃
• c) NF₃
• d) SbBr₃

Answer: NCl₃

Question:

• a) A = Excess, B = Excess
• b) A = Limited, B = Excess
• c) A = Excess, B = Limited
• d) A = Limited, B = Limited

Answer: A = Excess, B = Excess

Question: Which of the following is the strongest reducing agent

• a) BiH₃
• b) NH₃
• c) PH₃
• d) SbH₃

Answer: BiH₃

Question: Which of the following element will form acidic oxides of type E₂O₃

• a) P
• b) Sb
• c) As
• d) Bi

Answer: P

Question: Which one of the following is not an use of ammonia

• a) In the pickling of stainless steel
• b) As a refrigerate
• c) In manufacture of nitric acid
• d) To produce various nitrogenous fertilizers

Answer: In the pickling of stainless steel

Question:

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

Answer: (i), (ii) and (iii)

Question: Zinc on reaction with dilute HNO₃ gives x and zinc on reaction with concentrated HNO₃ gives y. Identify x and y

• a) x = N₂O , y = NO₂
• b) x = N₂O , y = NO
• c) x = NO , y = NO₂
• d) None of these

Answer: x = N₂O , y = NO₂

Question: Which of the following is incorrect for white and red phosphorus

• a) They are both soluble in CS₂
• b) They can be oxidised by heating in air
• c) They consist of the same kind of atoms
• d) They can be converted into one another

Answer: They are both soluble in CS₂

Question: Which of the following phosphorus is most reactive

• a) White phosphorus
• b) Violet phosphorus
• c) Red phosphorus
• d) Scarlet phosphorus

Answer: White phosphorus

Question: White phosphorus is

• a) P₄, a tetrahedral solid
• b) a linear diatomic molecule
• c) a monoatomic gas
• d) P₈, a crown

Answer: P₄, a tetrahedral solid

Question: Which property of white phosphorus is common to red phosphorous

• a) It burns when heated in air
• b) It reacts with hot caustic soda solution to give phosphine
• c) It shows chemiluminescence
• d) It is soluble in carbon disulphide

Answer: It burns when heated in air

Question: Which of the following statements regarding allotropic forms of phosphorus is incorrect?

• a) Red phosphorus on heating catches fire and give dense red fumes of P₄O₁₀
• b) White phosphorus is more reactive than red and black due to high angular strain
• c) Red phosphorus is polymeric in nature consisting of chains of P₄ tetrahedral
• d) None of these

Answer: Red phosphorus on heating catches fire and give dense red fumes of P₄O₁₀

Question: Which of the following is incorrect?

• a) Monoclinic sulphur is stable below 369 K
• b) Specific gravity of rhombic sulphur > specific gravity of monoclinic sulphur
• c) M.p of monoclinic sulphur > m.p. of rhombic sulphur
• d) Both rhombic sulphur and monoclinic sulphur have S₈ molecules.

Answer: Monoclinic sulphur is stable below 369 K