Chapter 5, Problem 19QP

Consider these changes.

(a)

$\text{Hg}\left(t\right)\to \text{Hg}\left(g\right)$

(b)

$\begin{array}{l}{\text{3O}}_{\text{2}}\left(g\right)\to 2{\text{O}}_{\text{3}}\left(g\right)\\ \end{array}$

(c)

${\text{CuSO}}_{\text{4}}\cdot 5{\text{H}}_{\text{2}}\text{O}\left(s\right)\to {\text{CuSO}}_{\text{4}}\left(s\right)+5{\text{H}}_{\text{2}}\text{O}\left(g\right)$

(d)

${\text{H}}_{\text{2}}\left(g\right)+{\text{F}}_{\text{2}}\left(g\right)\to 2\text{HF}\left(g\right)$

At constant pressure, in which of the reactions is work done by the system on the surroundings? By the surroundings on the system? In which of them is no work done?