Petroleum industry | Britannica (original) (raw)

Also known as: oil industry

Learn about this topic in these articles:

crude oil

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  In crude oil: Chemical and physical properties
  The petroleum industry, however, uses the American Petroleum Institute (API) gravity scale, in which pure water has been arbitrarily assigned an API gravity of 10°. Liquids lighter than water, such as oil, have API gravities numerically greater than 10. On the basis of their API gravity,…
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