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Name:  james d miks
Status: N/A
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Date: 1999 


Question:
Why is petroleum jelly not black, like asphalt, tar and other substances?



Replies:
The answer is in your subject line: it's a distillate. When crude oil is distilled, the gases are collected at different points along the column. The purest distillates are collected at the very top, I believe. What's left in the bottom of the pot is the black junky high molecular weight stuff. Petroleum jelly is actually petrolatum, and according to The Merck: A "purified mixture of semisolid hydrocarbons, chiefly of the methane series of the general formula CnH2n+2. Actually, petrolatum is a colloidal system of nonstraight-chain solid hydrocarbons and high-boiling liquid hydrocarbons, in which most of the liquid hydrocarbons are held inside micelles..."

-Joe Schultz



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