A monoatomic gas expands isobarically.What will be the percentage of heat supplied that increases the thermal energy and that involved in doing work for expansion?

Answer 1

The first law of thermodynamics
ΔQ =ΔU + W.
The work done by system is
W = p•ΔV =ν•R•ΔT.
The change in internal energy is
ΔU = ν•(i/2) •R•ΔT,
where the degrees of freedom i = 3,
ΔQ =ΔU + W = ν•(i/2) •R•ΔT + ν•R•ΔT = =2.5 •ν•R•ΔT,
ΔU/ ΔQ = ν•(i/2) •R•ΔT /2.5 •ν•R•ΔT =3/5 = 0.6.
60%
W/ ΔQ = ν•R•ΔT/2.5 •ν•R•ΔT = 0.4
40%