Identify the correct statement from below, concerning the structure of CH₂ = C = CH₂

• The molecule is planar

• One of the three carbon atoms is in an sp³ hybridized state

• The molecule is non-planar with the two -CH₂ groups being in planes perpendicular to each other

• All the carbon atoms are sp-hybridized

Molecular shapes of SF₄, CF₄, XeF₄ are :

• the same with 2, 0 and 1 lone pair of electron respectively

• the same with 1, 1 and 1 lone pair of electrons respectively

• different with 0, 1 and 2 lone pair of electrons respectively

• different with 1, 0 and 2 lone pair of electrons respectively

The presence of Ag⁺ ion increases the solubility of alkenes due to the formation of :

• d$\mathrm{\pi }$-dσ bonding

• pσ-p$\mathrm{\pi }$ bonding

• p$\mathrm{\pi }-\mathrm{d\pi }$ bonding

• None of the above

Each B - H - B bridge in B₂H₆ is formed by the sharing of:

• 2 electrons

• 4 electrons

• 1 electron

• 3 electrons

If the molecule of HCl were totally polar, the expected value of dipole moment is 6.12 D (debye), but the experimental value of dipole moment was 1.03 D. Calculate the percentage ionic character :

• 17

• 83

• 50

• Zero

Which one of the following molecules has the smallest bond angle ?

• NH₃

• PH₃

• H₂O

• H₂Se

Paramagnetism of oxygen is explained on the basis of its electronic configuration of

• ($\mathrm{\pi }$*2p_x)¹($\mathrm{\pi }$2p_y)¹

• ($\mathrm{\pi }$*2p_y)¹($\mathrm{\pi }$*2p_z)¹

• (σ*2s)¹($\mathrm{\pi }$2p_y)¹

• (σ*2s)¹($\mathrm{\pi }$2p_y)¹

Which of the following overlaps leads to bonding?

Which of the following statements is correct ?

• All carbon to carbon bonds contain a σ-bond and one or more $\mathrm{\pi }$-bonds

• All carbon to hydrogen bonds are $\mathrm{\pi }$-bonds

• All oxygen to hydrogen bonds are hydrogen bonds

• All carbon to hydrogen bonds are $\mathrm{\pi }$-bonds

An example of a polar covalent compound is :

• KCl

• NaCl

• CCl₄

• HCl