Question

What is the electronegativity of SP3 hybridised carbon(exact value).

Answer 1

Electronegative of hybrid orbitals depend upon % of s charater, as Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons.Hence more the s character more is the electronegativity.

In each sp3 orbital s character is 25%. Sp3 carbons are the least electronegative as the p character forces the electrons to exists further from the nucleus, decrease the electronegativity.
The carbon in Ch4 is sp3 hybridized which has 25% s-character. The electronegativity of C in Ch4 is 2.53.