Air flows at a steady rate through a horizontal pipe to a partly

closed valve. The pipe leaving the valve is enough larger than the

entrance pipe that the kinetic$-$energy change of the air as it flows

through the valve is negligible. The valve and connecting pipes

are well insulated. The conditions of the air upstream from the

valve are $20C$ and $6$ bar $,$ and the downstream pressure is $3$ bar. If

$($a$)$ Calculate t

the followi

$HCl(g)$:$-92$

$4$ HC

$($b$)$ Explain

substances.

the flow rate of air is $1mo\frac{l}{s}$ and if both upstream and

downstream pipes have an inner diameter of $5$ cm $,$ what is the

kinetic$-$energy change of the air and what is its temperature

change? For air, $C_P^{ik}=29\mathrm{.}100\frac{J}{m}ol$ and the molar mass is

$M=29\frac{g}{m}ol.$