The air within a piston equipped with a cylinder absorbs 565 j of heat and expands from an initial volume of 0.10 l to a final volume of 0.85 l against an external pressure of 1.0 atm. what is the change in internal energy of the air within the piston

489 J

Explanation:

According to the first law of thermodynamics:-

Where,

U is the internal energy

q is the heat

w is the work done

From the question,

q = + 565 J  (+ sign as the heat is being absorbed)

The expression for the calculation of work done is shown below as:

Where, P is the pressure

is the change in volume

From the question,

= 0.85 - 0.10 L = 0.75 L

P = 1.0 atm

Also, 1 atmL = 101.3 J

So,

(work is done by the system)

So,