0.5 mole of gas at temp 300 K expands
isothermally from an initial volume of 2.0L
to final volume of 6.0L. (a) What is the work
done by the gas ? (R = 8.31 J mol-1 K-1),
(b) How much heat is supplied to the gas?
Answers
Step-by-step explanation:
Solution: (a) The work done in isothermal
expansion is W = nRTln
V/Vfi
Where n = 0.5, Vf
= 6L, Vi
= 2L
W = 0.5 mol
8 319 300 62K
.ln mol
K L/L
= 1.369 kJ.
(b) From the first law of thermodynamics,
the heat supplied in an isothermal process
is spent to do work an a system. Therefore,
Q = W = 1.369 kJ.
Given: 0.5 moles of gas at temp 300 K expands
isothermally from an initial volume of 2.0L to a final volume of 6.0L.
To find: We have to find the work done by the gas and heat supplied to the gas.
Solution:
Work done by the gas is given as-
W=nRT ln(V2/V1)
Where n is the number of moles=0.5 moles.
R is the Rydberg constant=8.314
T is the temperature=300K.
V1 is the initial volume= 2L.
V2 is the final volume=6L.
Putting the values in the formula we get-
The work done by the gas is 1370J.
For the isothermal process heat supplied is equal to work done.
So, 1370J heat is supplied to the gas.