Question

Specify which atoms, if any, bear a formal charge in the Lewis structure given and the net charge for the species. Be sure to answer all parts.
a. Formal charge C:___________.
b. Formal charge N:________.
d. Net charge:________.

Answer 1

This is an incomplete question, here is a complete question.

Specify which atoms, if any, bear a formal charge in the Lewis structure given and the net charge for the species. Be sure to answer all parts.

$:C\equiv N:$

a. Formal charge C:___________.

b. Formal charge N:________.

d. Net charge:________.

Answer :

a. Formal charge C : (-1) charge

b. Formal charge N : (0) charge

d. Net charge : (-1) charge

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $CN^-$

As we know that carbon has '4' valence electrons and nitrogen has '5' valence electrons.

Therefore, the total number of valence electrons in $CN^-$ = 4 + 5 + 1 = 10

According to Lewis-dot structure, there are 6 number of bonding electrons and 4 number of non-bonding electrons.

Now we have to determine the formal charge for each atom.

Formula for formal charge :

$\text{Formal charge on C}=4-2-\frac{6}{2}=-1$

$\text{Formal charge on N}=5-2-\frac{6}{2}=0$

Thus, the net charge will be = -1 + 0 = -1