Pure ammonia is a clear liquid at normal temperatures with a pungent smell.

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They fill the container with pure air made by evaporating liquid nitrogen and liquid oxygen, and add water vapour and some trace gases.

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Your health, he said, handing Pereda the glass, which he half filled with a clear liquid that seemed to be pure alcohol.

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Fractionators take a mixed stream of natural gas liquids (the liquid stuff that comes out of the ground along with natural gas) and process it into pure products like ethane, propane and butane.

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