Question

Methane is tretrahedral but ethylene is a planar molecule why

Answer 1

ANSWER

Methane has sp3 hybridization, meaning that both have four bonds arranged with tetrahedral geometry.

while

In ethene, each hydrogen atom has one unpaired electron and each carbon is sp2 hybridized with one electron each sp2 orbital. The fourth electron is in the p orbital that will form the pi bond.