Physics problem need help?

Question

A 3.0-liter sample of an ideal gas is at a pressure of 2.5 atm at 15 deg C.

(i) How many moles of gas are in the sample?
(ii) If the volume does not change, what is the pressure of the gas when the temperature is 50 deg C?

please show work.

thank you.

Answer 1

Volume of the sample of the ideal gas,V = 3 L

Initial Pressure,P₁ =2.5 atm

Initial temperature,T₁ =15°C =288 K

Gas constant,R =  0.082057 L-atm/K-mol.

Calculate the  number of moles by using the ideal gas equation.

PV =n RT

n= PV/RT

n =(2.5)(3)/(0.082057)(288)

   =0.317 moles

Therefore, the  number of moles is 0.317 moles

 

Answer 2

ii)

Final pressure,T₂ =50°C =323 K

From the ideal gas law

P₁ /T₁ =P ₂ /T₂

P ₂ =P₁T₂ /T₁

       = (2.5)(323)/288

       =2.804 atm

Therfore, the pressure of the gas when the temperature is 50 deg C is 2.804 atm