Sketch the bonding involved in the molecule ethane, CH3CH3. How many sigma bonds are present? How many pi bonds are present? The bond between the two carbon atoms arises from overlap of a hybrid orbital on one carbon atom with a hybrid orbital on the other carbon atom.

Total number of sigma bonds = 7

Total number of pi bonds = 0

Carbon-carbon sigma bond is formed by the overlap of sp³ hybridized orbital of one carbon and sp³ hybridized orbital of other carbon.

Explanation:

Ethane is a linear alkane molecule as it is a saturated hydrocarbon molecule with no branching. This organic molecule is composed of 2 carbon atoms and 6 hydrogen atoms.

Since it is a saturated molecule, therefore, there are no pi bonds.

The molecular formula for ethane is: C₂H₆.

The structure of ethane is: H₃C - CH₃

Both the carbon atoms of the ethane molecule are sp³ hybridized. Therefore, each carbon atom has four sp³ hybridized orbitals.

In an ethane molecule, each carbon atom forms 3 sigma bonds with three hydrogen atoms, by the overlap of three sp³ hybridized orbitals with three 1s orbitals of three hydrogen atoms.

Therefore, the total number of carbon-hydrogen (C-H) sigma bonds in ethane = 3*2 = 6

While the remaining one sp³ hybridized orbital of one carbon atom overlaps with one sp³ hybridized orbital of the second carbon to form 1 carbon-carbon sigma bond.

Therefore, the total number of carbon-carbon (C-C) sigma bonds in ethane = 1

Therefore, the total number of sigma bonds in ethane = (C-C) sigma bonds + (C-H) sigma bonds = 6 + 1 = 7 sigma bonds.