calculate the new pressure if the gas is composed to 1.0 at constant temperature.?

Question

problem: a sample of gas is 1.5 atmosphere pressure in confined in a cylinder & occupies a volume of 2.0 liters.

Answer 1

You know the universal gas law, "pivnert:"

PV = nRT

Rearrange it by putting everything constant on the right. Actually, it's already arranged that way. Notice that nRT is always constant in this situation. Therefore, the term PV as a WHOLE, must stay constant. Therefore:

PV = PV or P1V1 = P2V2

(1.5)(2.0) = (1.0)P2

P2 = (1.5)(2.0)

P2 = 3.0 atm

Answer 2

So you take two litres of gas and compress it into 1 litre isothermally?

This is Boyle's law I think -
http://en.wikipedia.org/wiki/Boyle's_law
yes - so, if it was a perfect gas you have doubled the pressure.

Answer 3

From the ideal gas equation (P1)(V1)/(T1) = (P2)(V2)/(T2)
We get the P2 = 1.5*2/1 = 3 atmoshpheres