The P-Block Elements MCQ Type Questions ISC Class-12 Ch-7

(a) Non metallic character

(b) Inert pair effect

(c) High electronegativity

(d) Large ionization energy

Answer: (b) Inert pair effect

Question 3 : Boron shows diagonal relation with

(a) Al

(b) C

(c) Si

(d) Sn

Answer: (c) Si

Question 4 : H₂S is more acidic than H₂O because

(a) oxygen is more electronegative than sulphur.

(b) atomic number of sulphur is higher than oxygen.

(c) H — S bond dissociation energy is less as compared to H — O bond.

(d) H — O bond dissociation energy is less also compared to H — S bond.

Answer: (b) atomic number of sulphur is higher than oxygen.

Question 5 : Graphite has a structural similarity with

(a) B₂H₆

(b) B₄C

(c) B

(d) BN

Answer: (d) BN

Question 6 : Which of the following statements is not correct for nitrogen?

(a) Its electronegativity is very high

(b) d-orbitals are available for bonding

(c) It is a typical non-metal

(d) Its molecular size is small

Answer: (b) d-orbitals are available for bonding

Question 7 : Catenation property is maximum in

(a) phosphorus

(b) carbon

(c) sulphur

(d) zinc

Answer : (b) carbon

Question 8 : The boiling points of hydrides of group 16 are in the order

(a) H₂O > H₂Te > H₂S > H₂Se

(b) H₂O > H₂S > H₂Se > H₂Te

(c) H₂O > H₂Te > H₂Se > H₂S

(d) None of these

Answer : (b) H₂O > H₂S > H₂Se > H₂Te

Question 9 : Which is the correct order of decreasing acidity of lewis acids?

(a) BBr₃ > BCl₃ > BF₃

(b) BF₃ > BCl₃ > BBr₃

(c) BCl₃ > BF₃ > BBr₃

(d) BBr₃ > BF₃ > BCl₃

Answer: (a) BBr₃ > BCl₃ > BF₃

Question 10 :  In the presence of KF, AlF₃ is soluble in HF. Find the complex formed

(a) K₃[AlF₆]

(b) AlH₃

(c) K[AlF₃H]

(d) K₃[AlF₃H₃]

Answer: (a) K₃[AlF₆]

Question 11 : Collectively the elements of group 15 are called –

(a) pnicogens

(b) pnicopens

(c) nicopen

(d) None of these

Answer: (a) pnicogens

Question 12 :  Ionic radii (in Å) of As³⁺, Sb³⁺ and Bi³⁺ follow the order

(a) As³⁺ > Sb³⁺ > Bi³⁺

(b) Sb³⁺ > Bi³⁺ >As³⁺

(c) Bi³⁺ > As³⁺ > Sb³⁺

(d) Bi³⁺ > Sb³⁺ > As³⁺

Answer: (d) Bi³⁺ > Sb³⁺ > As³⁺

Question 13 : Which one of the following is an electrophilic reagent?

(a) BF₃

(b) KH₃

(c) H₂O

(d) None of these

Answer: (a) BF₃

Question 14 : Element found from sea water is

(a) magnesium

(b) Sodium

(c) Iodine

(d) None of these

Answer: (c) Iodine

Question 15: In the manufacture of sulphuric acid by contact process Tyndall box is used to

(a) convert SO₂ and SO₃

(b) test the presence of dust particles

(c) filter dust particles

(d) remove impurities

Answer: (b) test the presence of dust particles

Question 16: Fluorine differs from rest of the halogens in some of its properties. This is due to

(a) its smaller size and high electronegativity.

(b) lack of d-orbitals.

(c) low bond dissociation energy.

(d) All of the these.

Answer: (b) lack of d-orbitals.

Question 17: S-S bond is present in which of the ion pairs

(a) S₂O₇^2-, S₂O₃^2-

(b) S₄O₆^2-, S₂O₇^2-

(c) S₂O₇^2-, S₂O₈^2-

(d) S₄O₆^2-, S₂O₃^2-

Answer: (d) S₄O₆^2-, S₂O₃^2-

Question 18: Which is the correct order of decreasing bond dissociation enthalpy?

(a) F₂ > Cl₂ > Br₂ > I₂

(b) I₂ > Br₂ > Cl₂ > F₂

(c) Cl₂ > Br₂ > F₂ > I₂

(d) Br₂ > I₂ > F₂ > Cl₂

Answer: (c) Cl₂ > Br₂ > F₂ > I₂

Question 19: Which one of the following elements is most metallic ?

(a) P

(b) As

(c) Sb

(d) Bi

Answer: (d) Bi

Question 20: Which of the follow group 15 element forms metallic bonds in elemental state ?

(a) As

(b) P

(c) Sb

(d) Bi

Answer: (d) Bi

Question 21: The shape of XeF₄ is

(a) tetrahedral

(b) square planar

(c) pyramidal

(d) linear

Answer: (b) square planar

Question 22: Which one of the following is the strongest lewis acid?

(a) BF₃

(b) BCl₃

(c) BBr₃

(d) Bl₃

Answer: (d) Bl₃

Question 23: The set with correct order of acidity is

(a) HClO < HClO₂ < HClO₃ < HClO₄

(b) HClO₄ < HClO₃ < HClO₂ < HClO

(c) HClO < HClO₄ < HClO₃ < HClO₂

(d) HClO₄ < HClO₂ < HClO₃ < HClO

Answer: (b) HClO₄ < HClO₃ < HClO₂ < HClO

Question 24: When chlorine reacts with cold and dilute solution of sodium hydroxide, it forms

(a) Cl^– and ClO^–

(b) Cl^– and ClO₂^–

(c) Cl^– and ClO₃^–

(d) Cl^– and ClO₄^–

Answer: (a) Cl^– and ClO^–

Question 25: Oxygen is not released on heating which of the compounds?

(a) (NH₄)₂Cr₂O₇

(b) K₂Cr₂O₇

(c) Zn(ClO₃)₂

(d) KClO₃

Answer: (a) (NH₄)₂Cr₂O₇

Question 26:  Which of the species has a permanent dipole moment?

(a) SF₄

(b) SiF₄

(c) BF₃

(d) XeF₄

Answer: (a) SF₄

Question 27: The three important oxidation states of phosphorus are

(a) –3, +3 and +5

(b) –3, +3 and –5

(c) –3, +3 and +2

(d) –3, +3 and +4

Answer: (a) –3, +3 and +5

Question 28: Which of the following statement is incorrect for group 15 elements ?

(a) Order of ionization enthalpies is Δ_iH₁ < Δ_iH₂ < Δ_iH₃

(b) The boiling point and melting point increases from top to bottom in the group

(c) Dinitrogen is a gas while all others are solids

(d) All statements are correct

Answer: (b) The boiling point and melting point increases from top to bottom in the group

Question 29: Which one of the following does not form hydrogen bonding?

(a) NH₃

(b) H₂O

(c) HCl

(d) HF

Answer: (c) HCl

Question 30:  Main source of helium is

(a) Air

(b) Radium

(c) Monazite

(d) Water

Answer: (c) Monazite

Question 31: The formation of O₂⁺ [PtF₆]^– is the basis for the formation of first xenon compound. This is because

(a) O₂ and Xe have different sizes.

(b) both O₂ and Xe are gases.

(c) O₂ and Xe have comparable electro-negativities.

(d) O₂ and Xe have comparable ionisation enthalpies.

Answer: (d) O₂ and Xe have comparable ionisation enthalpies.

Question 32:  Partial hydrolysis of XeF₄ gives

(a) XeO₃

(b) XeOF₂

(c) XeOF₄

(d) XeF₂

Answer: (b) XeOF₂

Question 33: Which of the statement is incorrect for XeO₄ ?

(a) four p𝜋-d𝜋 bonds are present

(b) four sp³ – p 𝜎 bonds are present

(c) It has a tetrahedral shape

(d) It has a square planar shape

Answer: (d) It has a square planar shape

Question 34:P₄O₁₀ has ______ bridging O atoms

(a) 4

(b) 5

(c) 6

(d) 2

Answer: (c) 6

Question 35: Nitrogen is relatively inactive element because

(a) its atom has a stable electronic configuration

(b) it has low atomic radius

(c) its electronegativity is fairly high

(d) dissociation energy of its molecule is fairly high

Answer: (d) dissociation energy of its molecule is fairly high

Question 36: Which of the following has the highest pπ – pπ bonding tendency ?

(a) N

(b) P

(c) As

(d) Sb

Answer: (a) N

Question 37: Which one of the following dement is liquid at normal temperature?

(a) zinc

(b) mercury

(c) bromine

(d) water

Answer: (b) mercury

Question 38:   Which one of the following is least basic?

(a) NCl₃

(b) NBr₃

(c) NI₃

(d) NF₃

Answer: (c) NI₃

Question 39: Helium is preferred to be used in balloons instead of hydrogen because it is

(a) incombustible

(b) lighter than hydrogen

(c) more abundant than hydrogen

(d) non polarizable

Answer: (a) incombustible

Question 40: The increasing order of reducing power of the halogen acids is

(a) HF < HCl < HBr < HI

(b) HI < HBr < HCl < HF

(c) HBr < HCl < HF < HI

(d) HCl < HBr < HF < HI

Answer: (a) HF < HCl < HBr < HI

Question 41:  Pick out the wrong statement.

(a) Nitrogen has the ability to form pπ-pπ bonds with itself.

(b) Bismuth forms metallic bonds in elemental state.

(c) Catenation tendency is higher in nitrogen when compared with other elements of the same group.

(d) Nitrogen has higher first ionisation enthalpy when compared with other elements of the same group.

Answer: (c) Catenation tendency is higher in nitrogen when compared with other elements of the same group.

Question 42:  H₂SO₄ is a/an

(a) acid

(b) base

(c) alkali

(d) salt

Answer: (a) acid

Question 43: Nitrogen forms N₂, but phosphorus is converted into P₄ from P, the reason is

(a) Triple bond is present between phosphorus atom

(b) p_π – p_π bonding is strong

(c) p_π – p_π bonding is weak

(d) Multiple bond is formed easily

Answer: (c) p_π – p_π bonding is weak

Question 44: What causes nitrogen to be chemically inert ?

(a) Multiple bond formation in the molecule

(b) Absence of bond polarity

(c) Short internuclear distance

(d) High bond energy

Answer: (d) High bond energy

Question 45: Modern periodic table is given by

(a) Debonair

(b) Mendeleef

(c) Mendel

(d) None of these

Answer: (b) Mendeleef

Question 46: Which one of the following elements is found in free state in nature?

(a) Sodium

(b) Iron

(c) Zinc

(d) Gold

Answer: (d) Gold

Question 47: The structure of white phosphorus is

(a) square-planar

(b) pyramidal

(c) tetrahedral

(d) trigonal planar

Answer: (c) tetrahedral

Question 48: Arrange the following in decreasing Lewis acid strength -PF₃, PCI₃, PBr₃, Pl₃

(a) Pl₃ > PBr₃ > PCl₃ > PF₃

(b) PF₃ > PCl₃ > PBr₃ > Pl₃

(c) PCl₃ > PBr₃ > Pl₃ > PF₃

(d) PBr₃ > Pl₃ > PF₃ > PCl₃

Answer: (a) Pl₃ > PBr₃ > PCl₃ > PF₃

Question 49: Which of the following is a tetrabasic acid?

(a) Hypophosphorus acid

(b) Metaphosphoric acid

(c) Pyrophosphoric acid

(d) Orthophosphoric acid

Answer: (c) Pyrophosphoric acid

Question 50: Which of the following is not correctly matched?

(a) Acidic oxides-P₂O₅ NO₂, CL₂O₇

(b) Basic oxides-Na₂Om, CaO, MgO

(c) Neutral oxides-CO₂, CO, BeO

(d) Amphoteric oxides-ZnO, SnO,Al₂O₃

Answer: (c) Neutral oxides-CO₂, CO, BeO

-: End of The P-Block Elements MCQ Type Questions ISC Class-12 Ch-7  :

---

-: also visit :-

ICSE Class-12 Text book Solutions, Notes , Syllabus, Paper, Notes

Please share with your ISC friends if it is helpful

thanks