Physical Chemistry ${20241}^{st}$ Semester

Homework #$1($Due: $24\mathrm{.}04\mathrm{.}08)$

Problem $1(30$ pts$)$

E$1$C$.12$ At $300K$ and $20$atm, the compression factor of a gas is $0\mathrm{.}86.$ Calculate $($i$)$ the volume occupied by $8\mathrm{.}2$mmol of the gas molecules under these conditions and $($ii$)$ an approximate value of the second virial coefficient $B$ at $300K.$

Problem $2(40$ pts$)$

E$2$B$.8$ The constant$-$pressure heat capacity of a sample of a perfect gas was found to vary with temperature according to the expression $\frac{C_p}{J{K}^{-1}}=20\mathrm{.}17+0\mathrm{.}4001(\frac{T}{K}).$ Calculate $q,w,U,$ and $H$ when the temperature is raised from $25C$ to $100C($i$)$ at constant pressure, $($ii$)$ at constant volume.

Problem $3(30$ pts$)$

E$2$E$.8$ A sample consisting of $2\mathrm{.}5$mol of perfect gas molecules with $C_{p,m}=20\mathrm{.}8J{K}^{-1}mo{l}^{-1}$ is initially at $240$kPa and $325K.$ It undergoes reversible adiabatic expansion until its pressure reaches $150$kPa. Calculate the final volume and temperature, and the work done.