The gas that Dr. Walter Snelling discovered in 1911 that becomes a liquid under moderate pressure and acts as an energy source is propane.
Propane is a gas at room temperature and it was isolated by Dr. Walter Snelling around 1911 in the process of trying to stabilize gasoline.
At cold temperatures or moderate pressure, propane becomes a liquid.
Propane has been and is still being used as an energy source in cooking, powering vehicles, and cutting metals in industrial welding.
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