Identify a species which is not a Bronsted acid but a Lewis acid

• BF₃

• H${}_3^{+}$O

• NH₃

• HCl

12.

d²sp³ hybridisation of the atomic orbitals gives

• square planar structure

• triangular structure

• tetrahedral structure

• octahedral structure

The pH of 10^-8 M HCl solution is

• 8

• 6.9586

• more than 8

• slightly more than 7

A group of atoms can function as a ligand only when

• It is a small molecule

• It has an unshared electron pair

• Its a negatively charged ion

• It is a positively charge ion

Which of the following is diamagnetic?

• H${}_2^{+}$

• He${}_2^{+}$

• O₂

• N₂

The number of anti-boinding electron present in O${}_2^{+}$ molecular ion is

• 8

• 6

• 5

• 4

The process is spontaneous at the given temperature, if

• ΔH is +ve and ΔS is -ve

• ΔH is -ve and ΔS is +ve

• ΔH is +ve and ΔS is +ve

• ΔH is +ve and ΔS is equal to zero.

Mesomeric effect involves

• delocalisation of π- electron

• delocalisation of σ- electron

• partial displacement of electrons

• delocalisation of π and σ- electron

Alkali metals have negative reduction potential and hence they behave as

• oxidising agents

• Lewis bases

• reducing agents

• electrolytes

Cycloalkane formed when 1,4-dibromopentaneis heated with sodium is

• methyl cyclobutane

• cyclopentane

• cyclobutane

• methyl cyclopentane