What does "Diamond has Sp3 hybridised bonding" mean?

Answer 1

It means that the four valence e-'s of C are contained in four orbitals made up by hybridizing the 2s orbital with the three 2p orbitals. sp3 orbitals are oriented to the corners of a regulasr tetrahedron (trigonal pyramid). CCl4 isaan example. There is one C-Cl sticking "up in the air," while the C sits on a tripod of the other three C-Cl bonds. The Cl-C-Cl bond angles of CCl4 (and also the infinite number of C-C-C bond angles of diamond) are 104deg.

Answer 2

steve_geo is right.