Question

HELPP ?Air at a temperature of 27 C and 1 atm pressure in a 4 liter cylinder of a diesel engine There. By pushing the piston, the volume of air shrinks 16 times and the pressure increases 40 times. a) How many moles of air are in the cylinder. b) What is the final temperature of the air?

Answer 1

a. 0.16240664737515434 moles

b. 67.5 degrees Celcius

Step-by-step explanation:

a. Use Ideal Gas Equation

PV=nRT

Where P = pressure in pascals, V=Volume in cubic meters, n=number of moles, R is a constant=8.314 J/mol.K and T is temperature in Kelvin.

27C = 273+27=300Kelvin

volume 4L = 0.004m^3

Pressure = 1atm = 101325 Pascal

PV=nRT

101325Pa*0.004m^3=n*8.314J/mol.K*300K

Solving for n from the above you get n=0.16240664737515434 moles

b.Use combined gas law equation

P1*V1/T1=P2*V2/T2

P1= 1atm

V1=4L

T1=27C

P2= 4/16 L =0.25L

P=1*40 atm = 40atm

We do not know T2

USING THE FORMULA

(1atm*4L)/27C = (40atm*0.25L)/T2

(1*4)/27=(40*0.25)/T2

IF you simplify for T2, you get 67.5

Hence final temperature = 67.5 degrees Celcius