A gas is compressed from an initial volume of 5.35 L to a final volume of 1.23 L by an external pressure of 1.00 atm. During the compression the gas releases 128 J of heat.

Required:
What is the change in internal energy of the gas?

Respuesta :

Answer:

The change in internal energy is  [tex]\Delta U = 417331 \ J[/tex]

Explanation:

From the question we are told that

    The initial volume is  [tex]V_i = 5.35 \ L[/tex]

        The final volume is  [tex]V_f = 1.23 \ L[/tex]

     The value of the external pressure is  [tex]P = 1.00 \ atm = 1 * 101325 = 101325 \Pa[/tex]

      The energy released by the gas is  [tex]Q= -128 \ J[/tex]

The negative sign show that energy is released from the system

       

Generally  the workdone on the gas is mathematically represented as

         [tex]W = P (V_i - V_f)[/tex]

substituting values

         [tex]W = 101325 *(1.23 - 5.35)[/tex]

        [tex]W = - 4.17*10^{5} \ J[/tex]

The change in internal energy is mathematically evaluated as

         [tex]\Delta U = Q - W[/tex]

substituting values

         [tex]\Delta U = -128 - (-4.17*10^{5})[/tex]

        [tex]\Delta U = 417331 \ J[/tex]