What determines an object's potential energy?

The equation to determine it would be mass x acceleration x height, a objects potential energy is determined by these three factors.

Must be negative.substance increases

Ch4 and ph3 are both covalent since they are composed both of non-metals.    ch4 is non- polar because of  london forces and has a geometry of tetrahedral  ph3 , on the other hand, is umbrella shaped polar and has dipole-dipole intermolecular force (imf) . since ph3 is polar, it has a stronger imf