NEET Chemistry The P Block Elements MCQs Set A

Question: On moving down the group 13 density

• a) Increases
• b) Decreases
• c) First decreases then increases
• d) Remains same

Answer: Increases

Question: High melting point of boron is due to its existance as

• a) Small covalent molecule
• b) Giant covalent molecule
• c) Giant covalent solid
• d) Giant ionic molecule

Answer: Giant covalent solid

Question: Elements of group 13 mainly form covalent compounds because

• a) Size of ions is small
• b) Sum of three ionization energies is very high
• c) Electronegativity values are high
• d) All of these

Answer: All of these

Question: Oxidation state shown by group 13 elements is

• a) +1 and +3
• b) +1, +2 and +3
• c) +2, +3 and +4
• d) +1 and +4

Answer: +1 and +3

Question:  Which one of the following elements of group 13 can react with alkali solutions to give H₂ gas?

• a) Boron
• b) Aluminium
• c) Gallium
• d) All of these

Answer: All of these

Question: Lewis acid character of boron trihalides is as follows

• a) BI₃> BBr₃> BCl₃> BF₃
• b) BF₃> BCl₃> BBr₃> BI₃
• c) BCl₃> BF₃> BBr₃> BI₃
• d) BI₃> BBr₃< BF₃< BCl₃

Answer: BI₃> BBr₃> BCl₃> BF₃

Question:  Dimer Al₂Cl₆ is formed because

• a) Al is electron rich
• b) Aluminium is having lone pair of electron
• c) Aluminium forms coordinate bonds with chlorine to complete its octet
• d) Aluminium donates lone pair to form bridge

Answer: Aluminium forms coordinate bonds with chlorine to complete its octet

Question: When we heat borax strongly then it will yield the following compound

• a) NaBO₂   
• b) B₂O₃
• c) Na₂B₄O₇  
• d) Both (1) & (2)

Answer: Both (1) & (2)

Question:  B(OH)₃ accept how many OH^– ions?

• a) 1
• b) 2
• c) 3
• d) 4

Answer: 1

Question: Boric acid is having a polymeric type structure because of its

• a) Basic nature
• b) Acidic nature
• c) Hydrogen bonds
• d) Co-ordinate bonds

Answer: Hydrogen bonds

Question:  Select the incorrect statement for B₂H₆

• a) It contains B—B ionic bond 
• b) Each boron is sp³ hybridised
• c) It has two types of hydrogen bonds
• d) All of these

Answer:  It contains B—B ionic bond 

Question: In diborane each boron forms

• a) Two bonds
• b) Three bonds
• c) Four bonds
• d) Five bonds

Answer: Four bonds

Question: Which one of the following compounds has similar structure to that of graphite?

• a) Boron nitride
• b) Boron carbide
• c) Aluminium oxide
• d) Aluminium carbide

Answer: Boron nitride

Question: The number of sigma and pi bonds present in inorganic benzene are respectively

• a) 3σ, 12π
• b) 12σ, 3π
• c) 3σ, 3π
• d) 12σ, 12π

Answer:  12σ, 3π

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

Question: Aluminium is used for making alloys because of its

• a) Resistance to corrosion
• b) Poor conductivity
• c) Heaviness
• d) All of these

Answer: Resistance to corrosion

Question: Group 14 elements have general electronic configuration

• a) ns²
• b) ns²np⁴
• c) ns²np⁶
• d) ns²np²

Answer: ns²np²

Question:  Tendency of carbon for catenation is because carbon–carbon atom bond energy is

• a) Low
• b) High
• c) Zero
• d) Negative

Answer: High

Question: All elements except carbon have tendency to show maximum covalency of six

• a) Due to absence of vacant d-orbitals
• b) Due to presence of vacant d-orbitals
• c) Due to presence of partially filled d-orbitals
• d) Due to presence of completely filled d-orbitals

Answer: Due to presence of vacant d-orbitals

Question: Most abundant metal by mass in earth crust is

• a) Silicon
• b) Germanium
• c) Aluminium
• d) Arsenic

Answer: Aluminium

Question: Which one of the following elements is a metalloid?

• a) Carbon
• b) Germanium
• c) Lead
• d) All of these

Answer: Germanium

Question: On moving down the group, acidic nature of oxides of group 14

• a) Decreases
• b) Increases
• c) Remains same
• d) Increases then decreases

Answer: Decreases

Question: In diamond, carbon have

• a) sp³hybridisation 
• b) sp hybridisation
• c) sp² hybridisation
• d) sp³d² hybridisation

Answer:  sp³hybridisation 

Question:  Which one of the following elements forms double or triple bond involving pπ-pπ bonding?

• a) Carbon
• b) Silicon
• c) Germanium
• d) Tin

Answer: Carbon

Question: Allotropy is due to

• a) Difference in the number of atoms in the molecules
• b) Difference in the arrangement of atoms in the molecules in the crystal
• c) Difference in chemical properties
• d) All of these

Answer: Difference in the arrangement of atoms in the molecules in the crystal

Question: Graphite has

• a) 2-D sheet structure
• b) Van der Waals forces between different layers
• c) sp² hybridised carbon linked with other three carbon atoms in hexagonal planar structure
• d) All of these

Answer: All of these

Question: In graphite, the bond is

• a) Ionic
• b) Covalent
• c) Co-ordinate
• d) Metallic

Answer: Covalent

Question: Which one of the following is properties of CO gas?

• a) It is a colourless gas
• b) It is an odourless gas
• c) It is a neutral oxide
• d) All of these

Answer: All of these

Question: Carbonic acid is a

• a) Weak tribasic acid
• b) Weak dibasic acid
• c) Strong tribasic acid
• d) Strong dibasic acid

Answer: Weak dibasic acid

Question:  Organosilicon polymers containing Si—O—Si linkage is called

• a) Silicates
• b) Silicones
• c) Glass
• d) Silica

Answer: Silicones

Question:  SiO₄^4-  ion has geometry

• a) Triangular
• b) Tetrahedral
• c) Pentagonal bipyramidal
• d) Linear

Answer: Tetrahedral

Question: Maximum covalent character is shown by

• a) NCl₃ 
• b) PCl₃
• c) AsCl₃ 
• d) SbCl₃

Answer: NCl₃ 

Question:  HNO₂ on disproportionation gives HNO₃ and

• a) NO₂
• b) N₂O₅
• c) NO
• d) All of these can form

Answer: NO

Question: The correct order of acidic character is

• a) P₄O₁₀> P₄O₆
• b) N₂O₅> N₂O₃
• c) N₂O₃> P₄O₆
• d) All of these

Answer: All of these

Question: In which of the following reactions, products given are not correct?

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question:  Oxide of nitrogen which is acidic in nature and blue coloured liquid at –30°C

• a) N₂O  
• b) NO
• c) N₂O₃
• d) NO₂

Answer: N₂O₃

Question:  Covalency and oxidation numbers of nitrogen in N₂O₅ is respectively

• a) 5, +5
• b) 4, +5
• c) 3, +3
• d) 3, +5

Answer: 4, +5

Question: Which has maximum melting point?

• a) NH₃
• b) PH₃
• c) AsH₃
• d) SbH₃

Answer: NH₃

Question:  In which of the following N–N bond is not present?  

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

Answer:  N₂O₅ 

Question: Which set of oxide of nitrogen is paramagnetic in monomeric state?

• a) NO, N₂O  
• b) NO₂, N₂O 
• c) NO, NO₂ 
• d) N₂O, NO, NO₂

Answer:  NO, NO₂ 

Question: The incorrect statement among the following is

• a) Reducing character of hydrides of group 15 increases down the group
• b) Basicity of hydrides of group 15 increases down the group
• c) Phosphorus and arsenic can form pπ–dπ bond but not nitrogen 
• d) NCl₅ does not exist

Answer: Basicity of hydrides of group 15 increases down the group

Question:  Metal which become passive with conc. HNO₃

• a) Cr
• b) Zn
• c) Al
• d) Both (1) & (3)

Answer: Both (1) & (3)

Question:  Allotrope of phosphorus which is polymeric consisting of chains of P₄ tetrahedral linked together is

• a) White phosphorus
• b) Red phosphorus
• c) Yellow phosphorus
• d) Both (1) & (2)

Answer: Red phosphorus

Question: Which is dibasic?

• a) Orthophosphoric acid
• b) Pyrophosphoric acid
• c) Orthophosphorus acid
• d) Hypophosphorus acid

Answer: Orthophosphorus acid

Question:  In brown ring test for nitrate ions, brown ring is formed having composition

• a) [Fe(H₂O)₆]²⁺ 
• b) [Fe(H₂O)₅NO]²⁺
• c) [Fe(H₂O)₅NO]³⁺
• d) [Fe(H₂O)₅NO₂]²⁺

Answer:  [Fe(H₂O)₅NO]²⁺

Question:  Cyclotrimeta phosphoric acid has total number of P=O & P–O bonds respectively

• a) 5, 3
• b) 3, 9
• c) 3, 6
• d) 5, 6

Answer: 3, 9

Question: The one with lowest negative electron affinity in group 16 is Because of small

• a) Oxygen
• b) Sulphur
• c) Selenium
• d) Tellurium

Answer: Oxygen

Question:  The hybridisation and shape of SF₄ is respectively

• a) sp³d², square planar
• b) sp³d², octahedral 
• c) sp³d, see-saw
• d) sp³d, trigonal bipyramidal

Answer: sp³d, see-saw

Question: Correct order of boiling point of group 16 hydrides

• a) H₂O < H₂S < H₂Se < H₂Te
• b) H₂Te < H₂Se < H₂S < H₂O
• c) H₂S < H₂Se < H₂Te < H₂O
• d) H₂O < H₂Te < H₂Se < H₂S

Answer:  H₂S < H₂Se < H₂Te < H₂O

Question: Dioxygen can be prepared by

• a) Heating KClO₃ 
• b) Thermal decomposition of oxides like Ag₂O, Pb₃O₄ etc
• c) Electrolysis of water
• d) All of these

Answer: All of these

Question: The set containing acidic oxides only are

• a) SO₂, Cl₂O₇, CO
• b) Al₂O₃, NO, N₂O₅
• c) NO, N₂O₃, N₂O₅
• d) N₂O₃, SO₂, N₂O₅

Answer:  N₂O₃, SO₂, N₂O₅

Question: The incorrect statement regarding structure of ozone

• a) The two oxygen-oxygen bond length in ozone are identical
• b) It is linear
• c) Bond angle is less than 120º
• d) Both (2) & (3)

Answer: It is linear

Question: Form of sulphur which shows paramagnetic behaviour

• a) S₈– Rhombic
• b) S₈– Monoclinic  
• c) S₂ in vapour state 
• d) Not possible

Answer:   S₂ in vapour state 

Question: Which has bleaching action due to reduction and it is temporary?

• a) H₂O₂
• b) O₃
• c) SO₂ 
• d) Cl₂

Answer: SO₂ 

Question:  On reaction of moist SO₂ with potassium permangnate, (Acidic) which is correctly observed?

• a) Colour of KMnO₄ is decolourised
• b) SO₂ is oxidised to SO₃
• c) MnO^-₄ is reduced to MnO₂
• d) All of these

Answer:  Colour of KMnO₄ is decolourised

Question:  S–S bond is present in

• a) H₂S₂O₇  
• b) H₂S₂O₈
• c) H₂S₂O₆ 
• d) H₂SO₅

Answer:  H₂S₂O₆ 

Question: Deacon’s process of manufacture of chlorine is represented by the equation

• a)

  

• b)

  

• c)

  

• d)

  

Answer:

Question: The colour shown by halogen is incorrectly given by

• a) F₂= Yellow
• b) Cl₂= Colourless 
• c) Br₂= Red
• d) I₂= Violet

Answer: Cl₂= Colourless 

Question: Which is incorrectly given according to order indicated?

• a) F₂> Cl₂> Br₂> I₂; Oxidising power
• b) HI > HBr > HCl > HF ; Acidic strength
• c) F₂> Cl₂> Br₂> I₂; Bond dissociation enthalpy
• d) HF > HI > HBr > HCl ; Boiling point

Answer: F₂> Cl₂> Br₂> I₂; Bond dissociation enthalpy

Question:  Cl₂ on reaction with excess of NH₃ gives

• a) NH₄Cl + N₂ 
• b) NCl₃+ HCl 
• c) NH₄Cl only
• d) NH₄Cl + NCl₃

Answer: NH₄Cl + N₂ 

Question:  Cl₂ on reaction with cold and dilute NaOH gives NaCl and

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

Answer: NaOCl