What is the weight of a gallon of propane

Are Pounds of Propane Really Pounds of Weight?

I'm looking at an 11 pound (2 1/2 gallon) capacity propane canister. The canister itself reportedly weighs 13 pounds. When this filled canister is maxed out (which you shouldn't be doing anyway), does it weigh a maximum of 24 pounds (propane and tank together)?

This is the one I was looking at.

I lifted the propane tank in the store yesterday and it felt heavier than 13 pounds but was empty. I didn't weigh it so I could be wrong, but it felt a lot heavier. Would the air make that much difference in it?

Beanluc

Just so you know how much 5 gallons of air would weigh: en.wikipedia.org/wiki/Density_of_air At 0.0765 lb / (cuft)) and 0.133681 cuft / gallon we are talking about a hundredth of a pound, or a sixth ounce, or about 4.5 grams.

Charlie Brumbaugh

Yes, propane in pounds is measured by weight.

Answer: Propane can be measured in a number of ways. The most common route is through gallons. It can also be measured in pounds (one gallon = 4.2 pounds). When measuring in gallons, a meter on the pump is used to determine the amount of propane that has been placed in a tank. When measuring in pounds, the tare weight (empty start) of the tank must first be known.After taking this weight into account, the tank is filled with the correct volume.(i.e. a BBQ tank is commonly referred to as a 20 pound tank. This is because these tanks hold 20 pounds, or roughly 5 gallons of propane).

source

The simple answer to your second question is that you made a mistake in your estimate.

Jamin Gray

Many Thanks! I definitely overestimate weight as the most likely answer. So do I estimate how full a tank is by weighing it (using an actual scale = P) and comparing it to its curb weight?

Charlie Brumbaugh

@JaminGrey Yeah, that should work