Question

Draw the best lewis structure for cl3-. what is the formal charge on the central cl atom?

Answer 1

Answer : The formal charge on central Cl atom is -1.

Explanation :

The given molecule is, $Cl^-_3$

First we have to determine the total number of valence electrons in, $Cl^-_3$

As we know, chlorine has 7 valence electrons.

Total number of valence electrons in $Cl^-_3$ = 3(7) + 1 = 22 electrons

Electrons used in bonding pair = 4

Electrons used as lone pair = 22 - 4 = 18

Now we have to calculate the formal charge on central Cl atom.

• Formal charge = Number of valence electrons of a central atom - (2 × Number of lone pairs) - Number of bond pairs

Formal charge on central Cl atom = 7 - (2 × 3) -2 = -1

Therefore, the formal charge on central Cl atom is -1.

The lewis-dot structure of $Cl^-_3$ is shown below.