Which one of the following is not correct in respect of hybridization of orbitals?

• The orbitals present in the valence shell are hybridized

• The orbitals undergoing hybridization have akmost equal energy

• Pure atomic orbitals are more effective in forming stable bonds than hybrid orbitals

• It is not always that only partially filled orbitals participate in hybridization in some cases even filled orbitals in valence shell take part.

Allyl cyanide molecule contains

• 9 sigma bonds, 4 pi bonds and no lone pair

• 9 sigma bonds, 3 pi bonds and one lone pair

• 8 sigma bonds, 5 pi bonds and one lone pair

• 8 sigma bonds, 3 pi bonds and two lone pairs

Which one of the following statements is correct?

• Ferromagnetic substance like ZnFe₂O₄ becomes paramagnetic on heating

• NaCl is a paramagentic salt

• CuSO₄ is a diamagnetic salt

• MnO is an example of antiferronmagnetic substance

In the dichromate dianion, the nature of bonds are

• for equivalent Cr-O bonds

• six equivalent Cr-O bonds and one O-O bond

• six equivalent Cr-O bonds and one Cr-Cr bond

• six equivalent Cr-O bonds and one Cr-O-Cr bond

385.

Amongst the following ions which one has the highest magnetic moment value? (At. no. Co = 27, Ni = 28)

• [Co(NH₃)₆]³⁺

• [CoF₆]^3-

• [NiCl₄]^2-

• [Ni(CN)₄]^2-

Which among the following solid is a non-polar solid?

• Hydrogen chloride

• Sulphur dioxide

• Water

• Carbon dioxide

The number of sigma (σ) and pi ($\mathrm{\pi }$) bonds present in 1, 3, 5, 7-octatetraene respectively are

• 14 and 3

• 17 and 4

• 16 and 5

• 15 and 4

The molecule that contains only sp² hybrid carbon atoms is

• isoprene

• acrylonitrile

• but-1-ene

• 1,3-butadiene

Among the following, the molecule of highest dipole moment is

• CCl₄

• NH₃

• H₂O

• CHCl₃

The incorrectly matched pair, among the following is-

• BrF₅ - Trigonal bipyramidal

• SF₄ - See-saw

• ClF₃ - T-shape

• NH₃ - Trigonal pyramidal