Draw the best lewis structure for ch3-1. what is the formal charge on the c?

The most preferred Lewis structure of [CH₃]^– is given below.

The preferred or best Lewis structure for [CH₃]^– has a total of 8 valence electrons. The central carbon atom is bonded to three hydrogen atoms via single bonds, and it also has a lone pair of electrons.

Now we need to determine the formal charge on the C atom for the above CH₃^– lewis structure.

To calculate the formal charge on the central carbon atom, we use the formula given below:

Formal charge = valence electrons – non-bonding electrons – 1/2 * bonding electrons.

For the carbon atom in [CH₃]^–

⇒ Valence electrons of carbon = 4 (since it is in Group IV A)

⇒ Bonding electrons = 3 single bonds = 3 (2) = 6 electrons

⇒ Non-bonding electrons = 1 lone pair = 2 electrons

⇒ Formal charge on the carbon atom = 4 – 2 – 6/2 = 4 – 2 – 3 = -1

∴ Therefore, the formal charge on the central carbon atom in [CH₃]^– is -1.

Also check –

• CH₃⁺, CH₃^–, CH₃ formal charges with their lewis structure
• Formal charge calculator
• Lewis structure calculator