What is the approximate wavelength of visible light? a) 1 × 10–7 m b) 70 m c) 7 m d) 1 × 107 m

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