Objective Type Questions On Class 11 Chemistry Chapter 11 The P Block Elements

(1) The element which exists in liquid state for a wide range of temperature and can be used for measuring high temperature is

[A] B

[B] Al

[C] Ga

[D] In

Answer: Ga

(2) Which of the following is a Lewis acid ?

[A] AlCl3

[B] MgCl2

[C] CaCl2

[D] BaCl2

Answer: AlCl3

(3) The geometry of a complex species can be understood from the knowledge of type of hybridisation of orbitals of central atom. The hybridisation of orbitals of central atom in [Be(OH)₄]– and the geometry of the complex are respectively

[A] sp³ , tetrahedral

[B] sp³ , square planar

[C] sp³d ² , octahedral

[D] dsp² , square planar

Answer: sp³ , tetrahedral

(4) Which of the following oxides is acidic in nature?

[A] B₂O₃

[B] Al₂O₃

[C] Ga₂O₃

[D] In₂O₃

Answer: B₂O₃

(5) 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] Al

[C] Ga

[D] In

Answer: B

(6) Boric acid is an acid because its molecule

[A] contains replaceable H+ ion

[B] gives up a proton

[C] accepts OH– from water releasing proton

[D] combines with proton from water molecule

Answer: accepts OH– from water releasing proton

(7) Catenation i.e., linking of similar atoms depends on size and electronic configuration of atoms. The tendency of catenation in Group 14 elements follows the order:

[A] C > Si > Ge > Sn

[B] C >> Si > Ge ≈ Sn

[C] Si > C > Sn > Ge

[D] Ge > Sn > Si > C

Answer: C >> Si > Ge ≈ Sn

(8) Silicon has a strong tendency to form polymers like silicones. The chain length of silicone polymer can be controlled by adding

[A] MeSiCl₃

[B] Me₂SiCl₂

[C] Me₃SiCl

[D] Me₄Si

Answer: Me₃SiCl

(9) onisation enthalpy (∆_i H₁ kJ mol^–1) for the elements of Group 13 follows the order.

[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

(10) In the structure of diborane

[A] All hydrogen atoms lie in one plane and boron atoms lie in a plane perpendicular to this plane.

[B] 2 boron atoms and 4 terminal hydrogen atoms lie in the same plane and 2 bridging hydrogen atoms lie in the perpendicular plane.

[C] 4 bridging hydrogen atoms and boron atoms lie in one plane and two terminal hydrogen atoms lie in a plane perpendicular to this plane.

[D] All the atoms are in the same plane.

Answer: 2 boron atoms and 4 terminal hydrogen atoms lie in the same plane and 2 bridging hydrogen atoms lie in the perpendicular plane.

(11) A compound X, of boron reacts with NH₃ on heating to give another compound Y which is called inorganic benzene. The compound X can be prepared by treating BF₃ with Lithium aluminium hydride. The compounds X and Y are represented by the formulas.

[A] B2H6 , B3N3H6

[B] B2O3, B3 N3 H6

[C] BF3, B3N3 H6

[D] B3N3H6 , B2H6

Answer: B2H6 , B3N3H6

(12) Quartz is extensively used as a piezoelectric material, it contains ___________.

[A] Pb

[B] Si

[C] Ti

[D] Sn

Answer: Si

(13) The most commonly used reducing agent is

[A] AlCl₃

[B] PbCl₂

[C] SnCl₄

[D] SnCl₂

Answer: SnCl₂

(14) Dry ice is

[A] Solid NH₃

[B] Solid SO₂

[C] Solid CO₂

[D] Solid N₂

Answer: Solid CO₂

(15) Cement, the important building material is a mixture of oxides of several elements. Besides calcium, iron and sulphur, oxides of elements of which of the group (s) are present in the mixture?

[A] group 2

[B] groups 2, 13 and 14

[C] groups 2 and 13

[D] groups 2 and 14

Answer: groups 2, 13 and 14

(16) The reason for small radius of Ga compared to Al is _______.

[A] poor screening effect of d and f orbitals

[B] increase in nuclear charge

[C] presence of higher orbitals

[D] higher atomic number

Answer: A, B

(17) The linear shape of CO₂ is due to _________.

[A] sp3 hybridisation of carbon

[B] sp hybridisation of carbon

[C] pπ – pπ bonding between carbon and oxygen

[D] sp2 hybridisation of carbon

Answer: B, C

(18) Me3SiCl is used during polymerisation of organo silicones because

[A] the chain length of organo silicone polymers can be controlled by adding Me₃SiCl

[B] Me₃SiCl blocks the end terminal of silicone polymer

[C] Me₃SiCl improves the quality and yield of the polymer

[D] Me₃SiCl acts as a catalyst during polymerisation

Answer: A, B

(19) Which of the following statements are correct?

[A] Fullerenes have dangling bonds

[B] Fullerenes are cage-like molecules

[C] Graphite is thermodynamically most stable allotrope of carbon

[D] Graphite is slippery and hard and therefore used as a dry lubricant in machines

Answer: B, C

(20) Which of the following statements are correct. Answer on the basis of Fig

[A] The two birdged hydrogen atoms and the two boron atoms lie in one plane;

[B] Out of six B–H bonds two bonds can be described in terms of 3 centre 2-electron bonds.

[C] Out of six B-H bonds four B-H bonds can be described in terms of 3 centre 2 electron bonds;

[D] The four terminal B-H bonds are two centre-two electron regular bonds.

Answer: A, B, D

Objective Type Questions On Class 11 Chemistry Chapter 11 The P Block Elements

Download PDF

Chapters