Question

Part C

Go to the Phase Changes tab. Select the particular molecule, and set the temperature to the given values by using the stove to increase or decrease the temperature. Increase the pressure of the cylinder by moving the lid of the cylinder down with the help of the finger. The pressure of the cylinder is indicated by the pressure gauge on the top left corner of the simulation. On the right-hand side of the simulation is the phase diagram for the molecule.

As the molecules collide on the walls of the cylinder, the pressure of the cylinder does not remain constant; it fluctuates slightly as indicated by the gauge.

In the phase diagram, observe the red point. When a particular molecule is selected, set the temperature and pressure condition to the required value. Observe the position of the red point on the phase diagram when the pressure reaches approximately near the required value.

Which of the following conditions will result in the formation of a supercritical fluid?

Check all that apply.

1.	Oxygen at 100 K and no pressure
2.	Argon at 160 K and approximately 6 atm pressure
3.	Water at 294 K and approximately 1 atm pressure
4.	Neon at 32 K and approximately 1 atm pressure
5.	Neon at 50 K and approximately 10 atm pressure
6.	Water at 894 K and approximately 20 atm pressure
7.	Argon at 100 K and no pressure
8.	Oxygen at 194 K and approximately 2 atm pressure

Answer 1

The critical temperature and pressure of given gases are

Gas	Tc (K)	Pc(atm)
O2	154.6	49.78
H2O	647.1	217.72
Ar	150.9	48.35
Ne	44.5	27.32

If a substance is above critical pressure and critical temperature then it is in supercritical state

1.	Oxygen at 100 K and no pressure : Below critical pressure and temperature : So not in supercritical state
2.	Argon at 160 K and approximately 6 atm pressure: Above critical temperature: so in supercritical state
3.	Water at 294 K and approximately 1 atm pressure : Below critical temperature and pressure: so not in supercritical state
4.	Neon at 32 K and approximately 1 atm pressure: Below critical temperature and pressure: so not in supercritical state
5.	Neon at 50 K and approximately 10 atm pressure: Above critical temperature : so in supercritical state
6.	Water at 894 K and approximately 20 atm pressure: Above critical temperature : so in supercritical state
7.	Argon at 100 K and no pressure: Below Critical pressure and temperature: so not in supercritical state
8.	Oxygen at 194 K and approximately 2 atm pressure: Above critical temperature : so in supercritical state