Question

The reduced volume and reduced temperature of a gas are 10.2 and 0.7 respectively.If it's critical pressure is 4.25atm then its pressure will be
1)0.6816atm. 2)0.6618 atm. 3)0.8616atm. 4)zero

Answer 1

Hello Dear.

Answer ⇒ Option A. 

Solution :-

Given Conditions :-
Reduced Volume($V_{r}$) = 10.2
Critical Pressure($P_{c}$) = 4.25 atm.
Reduced Temperature($T_{r}$) = 0.7

Now, Using the Reduced Equation of the state :-

 $[P_{r} - \frac{3}{(V_{r})^{2} }] [V_{r} - \frac{1}{3}] = [\frac{8}{3} T_{r}]$

⇒ $[P_{r} - \frac{3}{(10.2)^{2} }] [10.2 - \frac{1}{3}] = [\frac{8}{3} 0.7]$

On Solving this Equating, We will get the Value of $P_{r}$ as 0.1603

Thus, Reduced Pressure is 0.1603.

Now, Using the Formula,
Pressure = Critical Pressure × Reduced Pressure.
Pressure = 4.25 × 0.1603
⇒ Pressure = 0.681275 atm.
∴ Pressure ≈ 0.6816 atm.


Hence, Option A is correct.


Hope it helps.