NEET Chemistry The P Block Elements MCQs Set C

Question:  The shape of ClF₂^–, is

• a) Linear
• b) Trigonal bipyramidal
• c) Square pyramidal
• d) T-shap

Answer: Linear

Question: Which of the following is called mixed anhydride?

• a) NO₂
• b) N₂O₃ 
• c) N₂O₅ 
• d) All of these

Answer:  NO₂

Question:  Reaction of Cl₂ with hot and conc. NaOH produces

• a) NaClO
• b) NaClO₃
• c) NaClO₄ 
• d) NaClO₂

Answer:  NaClO₃

Question: Which of the following do not exist?

• a) NCl₅ 
• b) PH₅
• c) [BCl₆]^3– 
• d) All of these

Answer: All of these

Question:  PCl₃+ H₂O—→ A + B. What are A and B

• a) H₃PO₂+ HCl 
• b) H₃PO₄+ HCl
• c) H₃PO₃+ HCl
• d) HPO₃+ HClO₃

Answer: H₃PO₃+ HCl

Question: Thermodynamically most stable allotrope of carbon is

• a) Fullerene
• b) Diamond
• c) Graphite
• d) All are equally stable

Answer: Graphite

Question: Which of the following is correct?

• a) In PF₅ , axial and equatorial bonds are interchanged, known as pseudoreaction
• b) In solid state PF₅ remains covalent
• c) PH₅ cannot be obtained, because H is not sufficiently electronegative to make the d-orbitals contact sufficiently
• d) All of these

Answer: All of these

Question: The variation of the boiling points of the hydrogen halides is in the order HF > HI > HBr > HCl. What explains the higher boiling point of hydrogen fluoride?

• a) The bond energy of HF molecules is greater than in other hydrogen halides
• b) The effect of nuclear shielding is much reduced in fluorine which polarises the HF molecule
• c) The electronegativity of fluorine is much higher than for other elements in the group
• d) There is strong hydrogen bonding between HF molecules

Answer: There is strong hydrogen bonding between HF molecules

Question: The stability of +1 oxidation state among Al, Ga, In and Tl increases in the sequence

• a) TI < In < Ga < Al
• b) In < Tl < Ga < Al
• c) Ga < In < Al < Tl
• d) Al < Ga < In < Tl

Answer: Al < Ga < In < Tl

Question: Which of the statements given below is incorrect?

• a) ONF is isoelectronic with O₂N^–  
• b) OF₂ is an oxide of fluorine
• c) Cl₂O₇ is an anhydride of perchloric acid     
• d) O₃ molecule is bent

Answer:  OF₂ is an oxide of fluorine

Question:  Strong reducing behaviour of H₃PO₂ is due to 

• a) High oxidation state of phosphorus
• b) Presence of two –OH groups and one P – H bond
• c) Presence of one –OH group and two P – H bonds
• d) High electron gain enthalpy of phosphorus

Answer:  Presence of one –OH group and two P – H bonds

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

Question: Acidity of diprotic acids in aqueous solutions increases in the order

• a) H₂S < H₂Se < H₂Te   
• b) H₂Se < H₂S < H₂Te
• c) H₂Te < H₂S < H₂Se   
• d) H₂Se < H₂Te < H₂S

Answer: H₂S < H₂Se < H₂Te   

Question: Which of the following structure is similar to graphite?

• a) B
• b) B₄C
• c) B₂H₆
• d) BN

Answer: BN

Question: Which of these is not a monomer for a high molecular mass silicone polymer?

• a) Me₂SiCl₂
• b) Me₃SiCl  
• c) PhSiCl₃
• d) MeSiCl₃

Answer:  Me₃SiCl  

Question: Which of these is least likely to act as a Lewis base ?

• a) F^– 
• b) BF₃
• c) PF₃
• d) CO

Answer: BF₃

Question: The basic structural unit of silicates is

• a)

  

• b)

  

• c)

  

• d) SiO^–

Answer:

Question: Which is the strongest acid in the following?

• a) HClO₃ 
• b) HClO₄ 
• c) H₂SO₃
• d) H₂SO₄

Answer:  HClO₄ 

Question: Which of the following is electron-deficient?

• a) (SiH₃)₂ 
• b) (BH₃)₂
• c) PH₃  
• d) (CH₃)₂

Answer:  (BH₃)₂

Question: Roasting of sulphides give the gas X as by product. This is a colourless gas with choking smell of burnt sulphur and causes great damage to respiratory organs as a result of acid rain. Its aqueous solution is acidic, acts as a reducing agent and its acid has never been isolated. The gas X is

• a) SO₂ 
• b) CO₂
• c) SO₃ 
• d) H₂S

Answer:  SO₂ 

Question:  XeF₂ is isostructural with 

• a) ICI₂^–   
• b) SbCl₃
• c) BaCl₂ 
• d) TeF₂

Answer:  ICI₂^–   

Question: Which of the following species contains three bond pairs and one lone pair around the central atom ?

• a) NH₂^–
• b) PCl₃
• c) H₂O 
• d) BF₃

Answer: PCl₃

Question: Which of the following does not give oxygen on heating?

• a) Zn(ClO₃)₂  
• b) K₂Cr₂O₇
• c) (NH₄)₂Cr₂O₇   
• d) KClO₃

Answer: (NH₄)₂Cr₂O₇   

Question: A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number?

• a) Cl
• b) C
• c) S
• d) H

Answer: Cl

Question:   When Cl₂ gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from 

• a) Zero to –1 and zero to +3
• b) Zero to +1 and zero to –3
• c) Zero to +1 and zero to –5
• d) Zero to –1 and zero to +5

Answer: Zero to –1 and zero to +5

Question: Which of the following statements is not valid for oxoacids of phosphorus?

• a) All oxoacids contain tetrahedral four coordinated phosphorus
• b) All oxoacids contain atleast one P = O unit and one P–OH group
• c) Orthophosphoric acid is used in the manufacture of triple superphosphate
• d) Hypophosphorous acid is a diprotic acid

Answer: Hypophosphorous acid is a diprotic acid

Question: Sulphur trioxide can be obtained by which of the following reaction

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which of the following is least likely to behave as Lewis base?

• a) OH^– 
• b) H₂O
• c) NH₃
• d) BF₃

Answer:  BF₃

Question:  Name the type of the structure of silicate in which one oxygen atom of [SiO₄]^4– is shared?

• a) Three dimensional
• b) Linear chain silicate
• c) Sheet silicate
• d) Pyrosilicate

Answer: Pyrosilicate

Question: In which of the following arrangements the given sequence is not strictly according to the property indicated against it?

• a) HF < HCl < HBr < HI : increasing acidic strength
• b) H₂O < H₂S < H₂Se < H₂Te : increasing pK_a values
• c) NH₃< PH₃< AsH₃< SbH₃: increasing acidic character
• d) CO₂< SiO₂< SnO₂< PbO₂: increasing oxidising power

Answer: H₂O < H₂S < H₂Se < H₂Te : increasing pK_a values

Question: Which of the following oxide is amphoteric ?

• a) SiO₂
• b) CO₂
• c) SnO₂
• d) CaO

Answer:  SnO₂

Question: The correct order of increasing bond angles in the following species are

• a) Cl₂O < ClO₂< ClO₂^–  
• b) ClO₂< Cl₂O < ClO₂^–
• c) Cl₂O < ClO₂^– < ClO₂
• d) ClO₂^– < Cl₂O < ClO₂

Answer: Cl₂O < ClO₂^– < ClO₂

Question: Which one of the following molecular hydrides acts as a Lewis acid ?

• a) NH₃  
• b) H₂O
• c) B₂H₆  
• d) CH₄BF₃

Answer: B₂H₆  

Question:  How many bridging oxygen atoms are present in P₄O₁₀ ? 

• a) 6
• b) 4
• c) 2
• d) 5

Answer: 6

Question:  The tendency of BF₃, BCl₃ and BBr₃ to behave as Lewis acid decreases in the sequence

• a) BCl₃> BF₃> BBr₃
• b) BBr₃> BCl₃> BF₃  
• c) BBr₃> BF₃> BCl₃ 
• d) BF₃> BCl₃> BBr₃

Answer:  BBr₃> BCl₃> BF₃  

Question: Which of the following molecules acts as a Lewis acid?

• a) (CH₃)₂O  
• b) (CH₃)₃P
• c) (CH₃)₃N 
• d) (CH₃)₃B

Answer:  (CH₃)₃B

Question: Among the following which is the strongest oxidising agent?

• a) Br₂ 
• b) I₂
• c) Cl₂  
• d) F₂

Answer:  F₂

Question: Which one of the following anions is present in the chain structure of silicates ?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: Which one of the following orders correctly represents the increasing acid strengths of the given acids ?

• a) HOClO₃< HOClO₂< HOClO < HOCl
• b) HOCl< HOClO < HOClO₂< HOClO₃
• c) HOClO₃< HOCl < HOClO₃< HOClO₂ 
• d) HOClO₂< HOClO₃< HOClO < HOCl

Answer:  HOCl< HOClO < HOClO₂< HOClO₃

Question: Which of the following oxidation states are the most characteristic for lead and tin respectively ?

• a) +2, +2
• b) +4, +2
• c) +2, +4
• d) +4, +4

Answer: +2, +4

Question:  Al₂O₃ can be converted to anhydrous AlCl₃ by heating 

• a) Al₂O₃ with HCl gas 
• b) Al₂O₃ with NaCl in solid state
• c) A mixture of Al₂O₃  and carbon in dry Cl₂ gas 
• d) Al₂O₃  with Cl₂ gas

Answer:  A mixture of Al₂O₃  and carbon in dry Cl₂ gas 

Question: Which of the following is the most basic oxide ?

• a) Al₂O₃ 
• b) Sb₂O₃
• c) Bi₂O₃ 
• d) SeO₂

Answer:  Bi₂O₃ 

Question: Which one of the following orders is not in accordance with the property stated against it ?

• a) F₂> Cl₂> Br₂> I₂: Oxidising power 
• b) HI > HBr > HCl > HF : Acidic property in water
• c) F₂> Cl₂> Br₂> I₂: Electronegativity
• d) F₂> Cl₂> Br₂> I₂: Bond dissociation energy

Answer:  F₂> Cl₂> Br₂> I₂: Bond dissociation energy

Question:  Which of the following is not isostructural with SiCl₄ ? 

• a) SCl₄
• b)

  

• c)

  

• d)

  

Answer:  SCl₄

Question: In which of the following molecules are all the bonds not equal?

• a) ClF₃
• b) BF₃
• c) AlF₃  
• d) NF₃

Answer:  ClF₃

Question: Which of the following is the electron deficient molecule?

• a) B₂H₆
• b) C₂H₆
• c) PH₃ 
• d) SiH₄

Answer:  B₂H₆

Question: Which statement is wrong?

• a) Feldspars are not aluminosilicates
• b) Beryl is an example of cyclic silicate
• c) Mg₂SiO₄ is orthosilicate
• d) Basic structural unit in silicates is the SiO₄ tetrahedron

Answer: Feldspars are not aluminosilicates

Question: Carbon and silicon belong to (IV) group. 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 low lying d-orbitals in silicon
• b) Large size of silicon
• c) More electropositive nature of silicon
• d) Both (2) & (3)

Answer: Availability of low lying d-orbitals in silicon

Question:  Which of the following statements about H₃BO₃ is not correct?

• a) It has a layer structure in which planar BO₃ units are joined by hydrogen bonds
• b) It does not act as proton donor but acts as a Lewis acid by accepting hydroxyl ion
• c) It is a strong tribasic acid
• d) It is prepared by acidifying an aqueous solution of borax

Answer: It is a strong tribasic acid

Question: Aluminium (III) chloride forms a dimer because aluminium

• a) Belongs to 3rd group
• b) Can have higher coordination number
• c) Cannot form a trimer
• d) Has high ionization energy

Answer: Can have higher coordination number

Question: Boron compounds behave as Lewis acids, because of their

• a) Ionisation property
• b) Electron deficient nature
• c) Acidic nature
• d) Covalent nature

Answer: Electron deficient nature

Question: In graphite, electrons are

• a) Localised on each C-atom
• b) Localised on every third C-atom
• c) Delocalised within the layer
• d) Present in anti-bonding orbital

Answer: Delocalised within the layer

Question: In borax bead test which compound is formed?

• a) Orthoborate
• b) Metaborate
• c) Double oxide
• d) Tetraborate

Answer: Metaborate

Question: The straight chain polymer is formed by

• a) Hydrolysis of (CH₃)₂SiCl₂ followed by condensation polymerisation
• b) Hydrolysis of (CH₃)₃ SiCl followed by condensation polymerisation 
• c) Hydrolysis of CH₃SiCl₃ followed by condensation polymerisation
• d) Hydrolysis of (CH₃)₄Si by addition polymerisation

Answer:  Hydrolysis of (CH₃)₂SiCl₂ followed by condensation polymerisation

Question: The metal oxide which cannot be reduced to metal by carbon is

• a) Fe₂O₃
• b) Al₂O₃ 
• c) PbO
• d) ZnO

Answer:  Al₂O₃ 

Question: In which of the following compounds, nitrogen exhibits highest oxidation state?

• a) N₃H  
• b) NH₂OH
• c) N₂H₄
• d) NH₃

Answer:  N₃H  

Question:  Which of the following displaces Br₂ from an aqueous solution containing bromide ions?

• a) I₂
• b) I₃^– 
• c) Cl₂
• d) Cl^–

Answer:  Cl₂

Question: Which of the following phosphorus is the most reactive?

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

Answer: White phosphorus

Question: Repeated use of which one of the following fertilizers would increase the acidity of the soil?

• a) Ammonium sulphate
• b) Superphosphate of lime
• c) Urea
• d) Potassium nitrate

Answer: Ammonium sulphate

Question: Which of the following oxides is most acidic?

• a) As₂O₅
• b) P₂O₅
• c) N₂O₅
• d) Sb₂O₅

Answer:  N₂O₅

Question: Which one of the following statements about the zeolite is false?

• a) They are used as cation exchangers
• b) They have open structure which enables them to take up small molecules
• c) Zeolites are aluminosilicates having three dimensional network
• d)

  

Answer: