Two separate flasks are each filled with a gas at 25.0°C; the valve between them is opened and the gases are allowed to mix. What would be the final pressure in torr after mixing, if initially H2 is in the first flask (Volume = 4.000 L) at 271.8 torr and CCl4 is in the second flask (Volume = 1.000 L) at 372.7 torr?

"Key Concept:In gas mixtures we use Dalton's law, which states that the total pressure is the sum of the partial pressures of the individualt gases. In an ideal situation each gas should obey the ideal gas law. Each gas expands to the fill the two flasks. Use Boyle's law to predict the partial pressure of each after expansion. Add partial pressures."

This is the long way around but I would do it this way but let me call your attention to the fact that CCl4 is NOT a gas at 25 C. Unless you clear up that part of the problem you are wasting your time on the rest of this.

Use PV = nRT for H2 and solve for n = number of mols.
Use PV = nRT for CCl4 gas and solve for n.
Add n H2 to n CCl4 = total n

Then PV = nRT, substitute the total n and the total V and final T and solve for P

To solve this problem, we can use Dalton's law of partial pressures. According to Dalton's law, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the individual gases.

First, we need to find the partial pressures of each gas after expansion. We can use Boyle's law, which states that the pressure of a gas is inversely proportional to its volume at constant temperature.

For the H2 gas in the first flask:
P1V1 = P2V2

P1 = initial pressure = 271.8 torr
V1 = initial volume = 4.000 L
P2 = final pressure (after expansion)
V2 = final volume (total volume of both flasks) = 4.000 L + 1.000 L = 5.000 L

Solving for P2:
P2 = P1 × (V1 / V2)
= 271.8 torr × (4.000 L / 5.000 L)
= 217.44 torr (rounded to two decimal places)

For the CCl4 gas in the second flask:
Using the same process with the given values, we can find the partial pressure of CCl4 after expansion to be 297.36 torr (rounded to two decimal places).

Finally, to find the total pressure, we add the partial pressures of H2 and CCl4:
Total pressure = Partial pressure of H2 + Partial pressure of CCl4
= 217.44 torr + 297.36 torr
= 514.8 torr

Therefore, the final pressure in torr after mixing would be 514.8 torr.