When a Mg2+ ion becomes a Mg atom, the radius increases because the Mg2+ ion

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   

Idont know. if you want an answer you need to give us some context dude.

Hi + naoh -> h2o + nal