Why Does the Ideal Gas Law Fail at the Critical Point of Carbon Tetrachloride?

AI Thread Summary
The Ideal Gas Law fails at the critical point of carbon tetrachloride due to the significant deviations from ideal behavior under high pressure and low temperature conditions. Calculations using the Ideal Gas Law yield a pressure of only 125.6 mmHg, while the literature reports a pressure of 34,181 mmHg at the critical point. This discrepancy highlights the limitations of the Ideal Gas Law in accurately predicting gas behavior near critical points. Additionally, the discussion raises questions about the correct units for density, indicating potential confusion in the calculations. Overall, the Ideal Gas Law is not applicable in this scenario, emphasizing the need for more complex models to describe real gas behavior.
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[SOLVED] ideal gas law numerically

If I calculate the pressure of water vapor at stp (in mmHg),
P= 1000*7.502e-3*R*(0+273)*.804/18;
where the 7.502e-3 factor converts from Pa to mmHg, 1000 is because my density (.804) is in grams/cm^3, 18 is the molar mass of water, etc etc. and this comes out to be 760mm (1atm), as expected. Now, here's the problem. I've got carbon tetrachloride at it's critical point. Literature shows its T_c = 283.15, density_c=.5576, and pressure_c = 34181 mmHg. However, if I just do
P= 1000*7.502e-3*R*(283.15+273)*.5576/154.01;
I get 125.6 mmHg, not 34181 mmHg. Where did I go wrong? Is it just that the dieal gas law fails, because I've also tried data points that aren't near the critical region and at room temp and neither work..
 
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Is your density in g/cm^3 or g/L ?
 
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
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