# chemistry

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A compressed gas cylinder contains 1.00 103 g of argon gas. The pressure inside the cylinder is 2035 psi (pounds per square inch) at a temperature of 15°C. How much gas remains in the cylinder if the pressure is decreased to 610. psi at a temperature of 30.°C?

Thanks for the help in advance :)

• chemistry -

Do you mean that you open the valve on the cylinder and release Ar gas until the pressure is decreased to 610 psi at 30 C?

• chemistry -

ohh yes i think so

• chemistry -

I would go to google, type in "2035 psi to atmospheres" without the quotation marks. Do the same for 610 psi. Then use PV = nRT to calculate n remaining in the vessel and convert that to grams. Subtract from the initial amount to obtain the grams Ar remaining.

• chemistry -

i found both atmospheres
2035=138.473537
610=41.508038

so it would be 1.00103(2035)=?

• chemistry -

I don't think so. You haven't used PV = nRT
I would substitute P, V, R, and T (don't forget to change T t Kelvin) from the final conditions and calculate n, number of moles. Then moles = grams/molar mass and determine grams, then subtract from the initial grams to find that remaining.