The binary hydrogen compounds of the group 4a elements and their boiling points are: ch4, -162°c; sih4, -112°c; geh4, -88°c; and snh4, -52°
c. explain the increase in boiling points from ch4 to snh4.

Explanation:

All the molecules of the 4a elements are nonpolar and tetrahedral (AH4).The intermolecular forces found between these molecules are dispersion forces.The critical factor behind the strength of dispersion forces is the number of electrons.As the number of electrons increases, the strength of dispersion forces increases.So, the dispersion forces and the boiling points increases as the molar mass increases from CH4 to SnH4.

Nonmetals usually react by gaining electrons