Question

A gas expands from 2 L to 6 L against a constant pressure of
0-atm on absorbing 200 J of heat. The change in internal energy
of the gas will be
(a) -2-6
(b) +26J
(c) 402-6J
(d) -402.63
d
ibh negathat​

Answer 1

Answer: −2.65 J

Explanation:q=200 J;ΔV=6−2=4 lit=0.004 m

3

; P=0.5×101325=50662.5 Pa

ΔH=ΔU+PΔV (enthalpy change)

At const, pressure (for isobar process ) ΔH=q

Hence, ΔU=q−PΔV (1

st

law of theromadynamics )

ΔU=200−50662.5×0.004=200−202.65

ΔU=−2.65 J