Which one of the followmg has no unpaired electrons?

• O${}_2^{-}$

• O${}_2^{+}$

• O${}_2^{2-}$

• O₂

The "spin only'' magnetic moment of Ni²⁺ in aqueous solution would be [At. no. of Ni = 28]

• $\sqrt{15}$ BM

• $\sqrt{2}$ BM

• $\sqrt{8}$ BM

• $\sqrt{6}$ BM

Impossible orbital among the following is

• 3f

• 2p

• 4d

• 2s

The total number of electrons in 18 mL of water (density = 1 g mL^-1) is

• 6.02 × 10²⁵

• 6.02 × 10²⁴

• 6.02 ×  18 × 10²³

• 6.02 × 10²³

The number of moles of hydrogen that can be added to 1 mole of an oil is the highest in

• groundnut oil

• sunflower seed oil

• mustard oil

• linseed oil

The equilibrium constant of a reaction is 0.008 at 298 K. The standard free energy change of the reaction at the same temperature is

• -11.96 kJ

• -5.43 kJ

• -8.46 kJ

• +11.96 kJ

The correct order of electronegativities of N, O, F and P is

• F > O > P > N

• F > O > N > P

• N > O > F > P

• F > N > P > O

8.

Which of the following is not a characteristic of a covalent compound?

• No definite geometry

• Insoluble in polar solvent

• Smal difference in electronegativity between the combining atoms

• Low melting point

The volume of 0.1 M oxalic acid that can be completely oxidized by 20 mL of 0.025 M KMnO₄ solution is

• 25 mL

• 12.5 mL

• 37.5 mL

• 125 mL

A ligand is a

• Bronsted acid

• either a Lewis acid or a Lewis base

• Lewis base

• Lewis acid