Calculating pressure in atmospheres of a gas??

Question

A 2.00 liter volume of gas has a temperature of -20°C and a pressure of .125 atmospheres. Calculate the pressure, in atmospheres, of the gas at 4.50 Liters and 57°C.

Answer 1

From the ideal gas law we can form the ratio P₂V₂ /P₁V₁ = T₂ /T₁ from which P₂ = P₁V₁T₂ / V₂T₁ = (0.125 atm)(2.00 L)(57 + 273K) / [(4.50 L)(-20 + 273K)] = 0.0725 atm.