Question

408 J of energy is transferred to a system consisting of 2.0 moles of an ideal gas. If the volume of this gas stays at a constant 4.4 L, calculate the change in internal energy of the gas.

Answer 1

Answer: The change in internal energy of the gas is +408 J

Explanation:

According to first law of thermodynamics:

$\Delta E=q+w$

$\Delta E$ =Change in internal energy

q = heat absorbed or released

w = work done or by the system

w = work done on the system= $-P\Delta V$

As volume is constant , $\Delta V$ = 0 and w = 0.

q = +408J   {Heat absorbed by the system is positive}

$\Delta E=+408J+(0J)=+408J$

Thus the change in internal energy of the gas is +408 J