QUESTION $1(20$ Marks$)$

If $1kg$ of nitrogen $(N_2)$ and $2kg$ of $CO,$ each at $\frac{1}{b}ar$ and $25C,$ blend to form a gas mixture at the same conditions, the gases are assumed ideal:

$($a$)$ What is the total change in entropy as a result of the process? Discuss if the process is reversible or irreversible.

$(8$ Maks$)$

$($b$)$ What is the change in enthalpy?

$(5$ Maks$)$

$($c$)$ Use the Lewis & Randall rule and the provided fugacity coefficent charts, to estimate the fugacity of $CO$ in an equimolar mixture of $CO$ and $N_2$ at $-70C$ and $300$atm.

$(7$ Maks$)$

QUESTION $2(20$ Marks$)$

One kilogram of water $)=(1003c{m}^3*k{g}^{-1}$ in a piston$/$cylinder device at $25C$ and $\frac{1}{b}ar$ is compressed in a mechanically reversible, isothermal process to $1500$ bar. A satisfactory assumption is that $V$ is constant at its arithmetic average value. Additional information:

$=250{10}^{-6}{K}^{-1}$ and $=()-1$

Determine the followings

$($a$)S$ and $H$

$(12$ Marks$)$

$($b$)U,Q,$ and W

$(8$ Marks$)$

QUESTION $3(20$ Marks$)$

A mixture containing equimolar amounts of benzene $(1),$ toluene $(2)$ and ethylbenzene $(3)$ is flashed at $110C$ and $90$kPa. Assuming that the Raoult's law is appropriate to this system, calculate the followings:

$($a$)$ Molar fraction $V$ of the vapours formed.

$(10$ Marks$)$

$($b$)$ Equilibrium mole fractions $(x_i,y_i)$

$(10$ Marks$)$