Hydrocarbons, usually produced with natural gas, which are liquid at normal pressure and temperature.
No.... Yes it was invented on an Oil Rig from a substance clogging the workers drills but it is not actually petroleum.
by adding waxes to base oils u can get petrolium jelly
If you mean purchase, then from any local gas station (Shell) . If you mean where it is obtained from, it is a form of oil which is extracted from the ground.
Carbon and Hydrogen