80 i need a step by step simple experiment to show that light travels in straight lines until at a point were it enters a new medium.

Materials: laser pointer/ flashlight with a paper with a small slit, glass prism

step 1.) turn on the laser pointer point it up to the ceiling.

step 2.) point to prism, explain how the light refracts in the prism. and how it changes.

(I hope this helps!)

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   

Ibelieve it is b. proton.hope my answer has you : )