Definition of «pure hydrogen»

"Pure hydrogen" refers to hydrogen that does not contain any other substances or impurities. It is just the element hydrogen by itself.

As an alternative, scientists have been trying to develop a cheap and efficient way to extract pure hydrogen from water. (sciencedaily.com)
The plan is to race the car, and complete a number of laps on pure hydrogen. (evo.co.uk)
The first is that applications for pure hydrogen are currently limited. (powermag.com)
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