Is petroleum a liquid

Answer 1

Most of the time. Here is one definition from "thefreedictionary": A thick, flammable, yellow-to-black mixture of gaseous, liquid, and solid hydrocarbons that occurs naturally beneath the earth's surface, can be separated into fractions including natural gas, gasoline, naphtha, kerosene, fuel and lubricating oils, paraffin wax, and asphalt and is used as raw material for a wide variety of derivative products. ====== Here's another from Merriam-Webster: an oily flammable bituminous liquid that may vary from almost colorless to black, occurs in many places in the upper strata of the earth, is a complex mixture of hydrocarbons with small amounts of other substances, and is prepared for use as gasoline, naphtha, or other products by various refining processes. ====== The first definition is a bit confusing as it sounds like petroleum is a mixture of solids, liquids and gases. In the reservoir, the oil phase can contained dissolved gas. When the oil is produced, the gas will come out of solution. Because of the liberation of gas, there is some shrinkage of oil. If there is any confusion, then it is better to state "hydrocarbon liquids", "crude oil" or "petroleum liquids."