211.

In which of the following molecules, maximum number of lone pairs is present on the central atom?

• NH₃

• H₂O

• ClF₃

• XeF₂

Match the following:

• A - 3; B - 2; C - 4; D - 1

• A - 2; B - 3; C - 4; D - 1

• A - 1; B - 3; C - 5; D - 4

• A - 4; B - 2; C - 3; D - 5

Which one of the following statements is not correct?

• O₃ is used as a germicide.

• In O₃ , O - O bond length is identical with that of molecular oxygen.

• O₃ is an oxidising agent

• The shape of O₃ molecule is angular.

Which among the following are having diamagnetic property?

(i) B₂    (ii) N₂    (iii)O₂   (iv) C₂

• II, III

• I ,IV

• II, IV

• I, II

A covalent bond between two atoms is formed by which of the following?

• Electron nuclear attraction

• Electron sharing

• Electron transfer

• Electrostatic attraction

Hybridisation involves

• addition of an electron pair

• mixing up of atomic orbitals

• removal of an electron pair

• separation of orbitals

On the basis of Molecular Orbital Theory (MOT) which molecule does not exist?

• H₂

• He${}_2^{+}$

• He₂

• Li₂

Which of the following compounds in liquid state does not have hydrogen bonding?

• H₂O

• HF

• NH₃

• C₆H₆

The Lewis structure for O₃ molecule is given below. The correct formal charges on oxygen atoms labelled 1, 2, 3 are respectively.

• -1, 0, +1

• +1, 0, -1

• +1, -1, 0

• 0, +1, -1

In which molecule are all atoms coplanar?

• CH₄

• BF₃

• PF₃

• NH₃