What is LPG | Liquid or GAS | Why is LPG called liquified Petroleum Gas

What is LPG | Liquid or GAS | Why is LPG called liquified Petroleum Gas

Many a times, we might have come across this confusion about the state of LPG, but all of us do have our own justification for the understanding. Lets see what is the actual fact behind this..

When LPG is Liquefied Petroleum Gas, indicating the Liquid state, why do we call it Cooking Gas?

Here’s the ice breaker about it:

LPG – Liquefied Petroleum Gas – is a liquid and a gas. It is a liquid under pressure or below -42°C (-44°F). It is a gas at 20°C (68°F) and 1 atm pressure (NTP) so, when released from a cylinder the propane liquid becomes gas.

LPG is both a liquid and a gas within the gas bottle.  LPG is gas vapor at the top of the bottle and liquid LPG at the bottom

LPG: Liquefied Petroleum Gas, is stored under pressure, as a liquid, in a gas bottle. It turns back into gas vapour when you release some of the pressure in the gas bottle by turning on your cooking stove or gas stove. Almost maximum applications of  LPG involve the use of the gas vapour, not the liquid. So if  LPG, is a Gas at both initial manufacturing time and at the end usage, then why do we convert and store it in Liquid state?

Density is the reason. Density of  LPG at gaseous state is just 2.15 kg/Cubic meter where as the same of liquid state is 553 kg/cubic meter. So for transportation ease LPG is always converted in to liquid which can occupy very less space for a kg of it.


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