Question

1)Which of the following is/are the possible methods of deciding which atom in the CN- ion has more negative charge?

Both methods mentioned.

Determine which atom is more electronegative.

Neither method mentioned is valid.

Determine the formal charge of each atom in the ion.

2)According to VSEPR theory, molecules generally adopt a structure that

separate electron pairs as far away from others as possible around the central atom of the molecule.

has the smallest number of valence electrons.

has the smallest number of lone pairs around the central atom.

has the smallest number of resonance structures.

Answer 1

Ans 1 : Both methods mentioned.

Both the methods determining the more electronegative element as well as the formal charge in the ion , determines which atom in the ion has more negative charge.

Since nitrogen is more electronegative than carbon , so the 3 electrons from carbon in the triple bond belongs to the nitrogen atom in the ion. So the carbon is left with only 2 valence electrons as compared to its 4 electrons earlier , so its oxidation number becomes +2 .