Answer
(a) 0
(b) -9.5 J
(c) -18 J
Work Step by Step
(a) $w=-P\Delta V=-(0)\Delta V=0$
Because the external pressure is 0, $w=0$.
(b) $\Delta V=89.3\,mL-26.7\,mL=62.6\,mL=0.0626\,L$
$w=-P\Delta V=-(1.5\,atm)(0.0626\,L)$
$=-0.0939\,L\cdot atm=-0.0939\,L\cdot atm\times\frac{101.3\,J}{1\,L\cdot atm}$
$=-9.5\,J$
(c) $w=-P\Delta V=-(2.8\,atm)(0.0626\,L)$
$=-0.17528\,L\cdot atm=-0.17528\,L\cdot atm\times\frac{101.3\,J}{1\,L\cdot atm}$
$=-18\,J$
