Which probably has the lowest boiling point at 1.0 atm pressure?

Question

Quizplus · Accepted Answer

Among the given options, CH4 (methane) has the lowest boiling point at 1 atm pressure. This is because, as the size and molecular weight of the element increases in the order Si < Ge < Sn < Pb, so does the strength of intermolecular forces that hold the molecules together. Methane has the weakest intermolecular forces among the options given, hence it requires the least amount of energy to break these forces and boil.

Which Probably Has the Lowest Boiling Point at 1