Assertion : [Fe(CN)₆]^3- has d²sp³ type hybridisation.

Reason: [Fe(CN)₆]^3- ion shows magnetic moment corresponding to two unpaired electrons.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion.

• If assertion is true but reason is false

• If both assertion and reason are false.

Assertion: Both $\mathrm{\pi }$(2p_x) and $\mathrm{\pi }$^*(2p_x) MO's have one nodal plane.

Reason : All MO's formed by side way overlapping of 2p- orbitals have one nodal plane.

• If both assertion and reason are true and reason is the correct explanation of assertion.

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false

• If both assertion and reason are false.

Which of the following molecules has more than one lone pair ?

• SO₂

• XeF₂

• SiF₄

• CH₄

Each NH₃ molecule has six other NH₃ molecules as nearest neighbours in solid state ; $∆$H of sublimation of NH₃ molecule at the m.p. is 30.8 kJ mol^-1 and in the absence of H-bonding estimated Ml of sublimation is 14.4 kJ mol^-1 .Hence , strength of H-bond in solid NH₃ is :

• 5.47 kJ mol^-1

• 10.93 kJ mol^-1

• 16.40 kJ mol^-1

• - 16.40 kJ mol^-1

765.

Four diatomic species are listed below in different sequences. Which of these represents the correct order of their increasing bond order?

• ${\mathrm{C}}_2^{2-}$ < ${\mathrm{He}}_2^{+}$ < NO < ${\mathrm{O}}_2^{-}$

• ${\mathrm{He}}_2^{+}$ < ${\mathrm{O}}_2^{-}$ < NO < ${\mathrm{C}}_2^{2-}$

• ${\mathrm{O}}_2^{-}$ < NO < ${\mathrm{C}}_2^{2-}$ < ${\mathrm{He}}_2^{+}$

• NO < ${\mathrm{C}}_2^{2-}$ < ${\mathrm{O}}_2^{-}$ < ${\mathrm{He}}_2^{+}$

Which one ofthe following is not tetrahedral in shape ?

• SiCl₄

• N${\mathrm{H}}_4^{+}$

• CH₄

• SF₄

N₂O is isoelectronic to CO₂ and ${\mathrm{N}}_3^{-}$. Which of the following is the structure of N₂O ?

• 

• N-O-N

• N-N-O

• 

Number of lone pair in XeOF₄ is :

• zero

• one

• two

• three

Assertion : C- $\underset{..}{\overset{..}{O}}$ - H bond angle is less than the normal tetrahedral bond angle.

Reason : Lone pair-lone pair repulsion decreases bond angle.

• If both assertion and reason are true and reason is the correct explanation of assertion

• If both assertion and reason are true but reason is not the correct explanation of assertion

• If assertion is true but reason is false.

• If both assertion and reason are false.

The geometry of ammonia is :

• tetrahedral

• pyramidal

• triangular

• trigonal bipyrarnidal