which has higher boiling point CH4 or SiH4 ,,, (ans = si4) why???
Both SiH4 and CH4 have simple molecular structures with molecules and are held together by induced dipole-induced dipole (id-id) interactions or London dispersion forces.
The strength of these forces increases with the number of polarizable electrons and therefore usually increases with molecular weight of the molecule.
SiH4 molecules have a greater number of electrons (greater molecular weight) than CH4 molecules.
As a result, the id-id interactions between SiH4 molecules are stronger than those between CH4 molecules and require a greater amount of energy to overcome these interactions.
Hence boiling point of SiH4 is greater than boiling point of CH4.