imperial u.k question.liquid propane,and water?

Question

this question is as it is,not metric conversions,6.1/4 gallons of water at 65 fahrenheit=1 cubic foot,i say 65 fahrenheit as if the temperature was higher the water would expand,...liquid propane gas stays liquid only under pressure,normal propane gas bottles hold a pressure of about 80 psi,if this pressure altered to 50 psi,would this mean the gas would expand...what do you think.

Answer 1

It wouldn't make one iota of difference if you tried to lower the pressure to 50 psi. As a matter of fact you wouldn't be able to reduce the pressure to 50 psi - the propane would remain at it's Vapour Pressure for whaatever temperature it is kept at. You would only achieve 50psi by almost totally emptying the bottle, then you would have enough gas for approximately 20 seconds of use. You MUST have liquid remaining in the bottle, in order to have any real use of the gas. When you open the valve at the top of the bottle, you instantly expose the liquid to atmospheric pressure, which will also be far above the boiling point of propane. That's why it turns to gas instantly. This is a subject which interests me very much.

If you have a vapour space in the bottle (which you will), then you can only alter the pressure in the bottle by altering the temperature. By altering the temperature, you alter the Vapour Pressure of the liquid. Increase temperature, the pressure rises, and vice versa.

Think of it like this - At atmospheric pressure, liquid propane will boil at approximately minus 42 degrees C. If you took that bottle of propane to a barbeque in Alaska, where it was minus 43 degrees outside, you would open the valve at the top and nothing would come out. Your barbie would be cancelled. This is because the Vapour Pressure of the liquid propane, at that temperature, would be equal or lower than the pressure outside the bottle.

Answer 2

There are two metric conversion science teams that work to
keep concentrated formula in protrend. This is flight fuel leads.
Because a general motor can run at higher rpom then there is
such a fuel. Propeldylenitren, propylic sianide, propylinium
dilithiul and so on, all these fuels are after burn proficient.
The fuel was chose because of these safety allies. Over 80
fuel condensed formulas can be designed for launch fuel.

Answer 3

Yes of course. If the gas is under less pressure, it has more space to move. The way to cause this pressure change would be to let gas out of the bottle.