Question

A gas is enclosed in a cylinder fitted with a light frictionless piston and maintained at atmospheric pressure. When 7950 kcal of heat is added to the gas, the volume is observed to increase slowly from 12.8 m^3 to 19.4 m^3.

Required:
a. Calculate the work done by the gas. Express your answer with the appropriate units.
b. Calculate the change in internal energy of the gas, Express your answer with the appropriate units.

Answer 1

Step-by-step explanation:

From the question we are told that:

Energy
`Q=7950kcal=3.3*10^7`

Initial Volume
`V_1=12.8 m^2`

Final Volume
`V_2=19.4 m^2`

a)

Generally the equation for Work done is mathematically given by

`W=P \triangle V`

Where

`P= Pressure at 1atm`

Therefore

`W=(1.01*10^5)(19.4-12.8)`

`W=6.67*10^5J`

a)

Generally the equation for Change in internal energy of the gas is mathematically given by

`\triangle U=Q-W`

`\triangle U=3.3*10^7-6.67*10^5J`

`\triangle U=3.2*10^7J`