The kind of plastic in plastic cups vs styrofoam cups
Plastic is made almost entirely of hydrocarbons, and Styrofoam is just another kind of plastic, but with lots of air bubbles in it.
Styrofoam is foamed polystyrene. Please be aware that there is an immense number of different polymers in use today. The only ones that are hydrocarbons, in the sense of containing only hydrogen and carbon, are polyethylene, polypropylene, polybutene [butyl rubber], and polyisoprene [natural rubber, though suilfur is added to vulcanize it]. All polymers do have other stuff added to them; antioxidants, mold release/extrusion lubricants, fillers, etc etc etc. However, perhaps what you meant to ask was what polymer uses less oil to make ? To a first approximation, the weight of the two cups would be a good indicator. To get more accurate than that, you need to know the efficiencies of making the polymers, and I don't, sorry. The easiest way to tell what the plastic cup is made of is to look at the recycling number and letters. pete = poly ethylene terephthalate, PET to those in the polymer industry PP = polypropylene I strongly suspect it will be one of those two. Or perhaps you meant which has more free hydrocarbons ? I would guess the order to be [hi to lo] styrofoam, PP, then PET, but I am not really sure.
