Thermodynamics and Thermochemistry 1 Question 18

«««< HEAD

21. $\Delta U$ is equal to

======= ####21. $\Delta U$ is equal to

3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed (a) isochoric work

(b) isobaric work

(c) adiabatic work

(d) isothermal work

Show Answer

Solution:

  1. According to first law of thermodynamics,

$$ \Delta U=q+W=q-p \Delta V $$

In isochoric process $(\Delta V=0), \Delta U=q$

In isobaric process $(\Delta p=0), \Delta U=q$

In adiabatic process $(q=0), \Delta U=W$

In isothermal process $(\Delta T=0)$ and $\Delta U=0$

$\therefore \Delta U$ is equal to adiabatic work.