Question

What is sigma and pi bond?

Answer 1

Hint :the gain or loss of electrons cannot take place between similar atoms during the formation of the molecule. In such cases the bond is formed by mutual sharing of electrons. A force that binds atoms of same or different elements by mutual sharing of electrons is called a covalent bond.

Complete Step By Step Answer:
The atoms involved in bond formation contribute equal numbers of electrons for sharing. The shared electrons become a common property of both the atoms and constitute a bond between them. The shared pair of electrons which is responsible for the formation of bonds is also called the bond pair of electrons. Sigma and pi bonds are chemical covalent bonds. When there is overlapping of atomic orbitals, sigma and pi bonds are formed.
Talking about sigma, they are formed by end to end overlapping whereas Pi bonds are formed when the lobe of one atomic orbital overlaps another. Sigma bonds resemble the shape of s orbital and Pi bond resembles the shape of P orbitals in symmetry. Generally, sigma bonds are present when there is a minimum of two one bonds present between the molecule, in unsaturated compounds. For example, ethane has $ C{H_3} - C{H_3} $ . It has a total of 7 sigma bonds. Pi bond to exist requires saturated compounds. In ethene there is 1 Pi bond and 5 sigma bond. In double bonds, there is 1 pi and 1 sigma. Similarly in the triple bond there is 2pi and 1 sigma .

Note :
The Sigma bond symbol is $ \sigma $ and that of Pi bond is $ \pi $ . It has been referred to as the strongest type of covalent bond because the extent of overlapping is maximum when there is formation of molecules.