A 265 gal storage tank contains 88.5 kg methane ( CH4) . If the temperature reaches 42 ∘C, what is the pressure inside the tank?

Answer 1

Hello, Andrea,

We need the ideal gas law, PV = nRT (Pressure, Volume, moles(n), gas constant(R), and Temperature in Kelvin).

We have mass and volume, so we can find moles. First, covert kg mass to grams, and gallons to liters:

88.5 kg = 88,500 g

265 gallons = (265 gal)*(3.758 liters/gal) = 1003.1 liters

Now calculate moles CH₄ (88,500 grams/16 grams/mole) = 5531 moles

The gas constant I'll use is 0.082058 L-atm*K^-1mol^-1

Temperature is 315.15K

Put these into a reformatted ideal gas law (to find P):

P = (nRT)/V

The units should cancel, leaving just atm.

Check my calculations. The answer I got is 142.6 atm.

That seems awfully high to me. Where is this bomb tank located? But maybe I missed a digit in enetering tha data. Also, double check my logic.

Bob

Answer 2

Use the formula, PV = nRT

Change the 265 gallons into Liters

Change the 88.5kg of methane into moles of methane using the molar mass of methane

Change 42°C into °K.

R = 0.0821 atm*L/mol/°K

Lastly, plug in and solve for P