Question

One mole of an ideal gas with `gamma` = 1.4 is adiabatically compressed so that its temperature rises from 27° C to 47° C. The change in the internal energy of the gas is (R = 8.3 J/mol.K) ____________.

Options

• - 415 J

• 415 J

• - 168 J

• 168 J

Answer 1

One mole of an ideal gas with `gamma` = 1.4 is adiabatically compressed so that its temperature rises from 27° C to 47° C. The change in the internal energy of the gas is 415 J.

Explanation:

Change in internal energy of the gas,

`Delta "U" = -Delta"W" = ("R"("T"_2 - "T"_1))/(gamma - 1)`   ....`(because "n"= 1)`

`= 8.3/(1.4 - 1)  (320 - 300)`

` = 415  "J"`