The number of antibonding electron pairs in O${}_2^{2-}$ molecular ion on the basis of molecular orbital theory is (Atomic number of O is 18)

• 5

• 4

• 3

• 2

Maximum number of molecules of CH₃I that can react with a molecule of CH₃NH₂ are

• 3

• 4

• 2

• 1

An octahedral complex is formed when hybrid orbitals of the following type are involved

• sp³

• dsp²

• d²sp³

• sp²d²

The angle strain in cyclobutane is

• 24°44'

• 29°16'

• 19°22'

• 9°44'

The correct statement with regard to ${\mathrm{H}}_2^{+} \mathrm{and} {\mathrm{H}}_2^{-}$ is

• both ${\mathrm{H}}_2^{+} \mathrm{and} {\mathrm{H}}_2^{-}$ are equally stable

• both ${\mathrm{H}}_2^{+} \mathrm{and} {\mathrm{H}}_2^{-}$ do not exist

• H${}_2^{-}$ is more stable than H${}_2^{+}$

• H${}_2^{+}$ is more stable than H${}_2^{-}$

Arrange the following in the increasing order of their bond order

O₂, O${}_2^{+} , {\mathrm{O}}_2^{-} \mathrm{and} {\mathrm{O}}_2^{2-}$

• ${\mathrm{O}}_2^{2-}, {\mathrm{O}}_2^{-}, {\mathrm{O}}_2, {\mathrm{O}}_2^{+}$

• ${\mathrm{O}}_2^{2-}, {\mathrm{O}}_2^{-}, {\mathrm{O}}_2^{+}, {\mathrm{O}}_2$

• ${\mathrm{O}}_2^{+}, {\mathrm{O}}_2, {\mathrm{O}}_2^{-}, {\mathrm{O}}_2^{2-}$

• ${\mathrm{O}}_2, {\mathrm{O}}_2^{+}, {\mathrm{O}}_2^{-}, {\mathrm{O}}_2^{2-}$

Among the following, the compound that contains ionic, covalent and co-ordinate linkage is

• NH₃

• NH₄Cl

• NaCl

• CaO

A covalent molecule AB₃ has pyramidal structure. The number of lone pair and bond pair of electrons in the molecule are respectively

• 2 and 2

• 0 and 4

• 3 and 1

• 1 and 3

The magnetic moment of a transition metal ion is $\sqrt{15}$ BM. Therefore, the number of unpaired electrons present in it is

• 3

• 4

• 1

• 2

540.

Which one of the following conversions involve change in both hybridisation and shape?

• CH₄ → C₂H₆

• NH₃ → NH${}_4^{+}$

• BF₃ → BF${}_4^{-}$

• H₂O → H₃O⁺