A 355.0 mL cylinder containing SO3 at a pressure of 0.700 atm is connected by a valve to 0.559 L cylinder containing COCl2 at 380.0 torr pressure. Calculate the partial pressure (atm) of SO3 when the valve is opened.

Unit conversion
K = C + 273
1 atm = 760 torr

Molar Mass (g/mol)
SO3 80.063
COCl2 98.916

Use PV = nRT to calcualte n for SO3 in the tank. Then use PV = nRT to calculate p for the new volume of both tanks.

To calculate the partial pressure of SO3 when the valve is opened, we need to use the ideal gas law equation:

PV = nRT

Where:
P is the pressure in atm
V is the volume in liters
n is the number of moles
R is the ideal gas constant (0.0821 L·atm/mol·K)
T is the temperature in Kelvin

First, let's calculate the number of moles of SO3 in the 355.0 mL cylinder. We'll use the ideal gas law equation and rearrange it to solve for n:

n = PV / RT

P = 0.700 atm
V = 355.0 mL = 0.355 L
R = 0.0821 L·atm/mol·K
T = temperature in Kelvin (unknown)

Now, let's calculate the number of moles of COCl2 in the 0.559 L cylinder. We'll use the same equation:

n = PV / RT

P = 380.0 torr = 380.0/760 = 0.5 atm (converting torr to atm)
V = 0.559 L
R = 0.0821 L·atm/mol·K
T = temperature in Kelvin (unknown)

Since both gases are at the same temperature and connected by a valve, we can assume they are at the same temperature.

Now, let's calculate the total number of moles of gas in the system. We add the moles of SO3 and COCl2 together:

Total moles = moles of SO3 + moles of COCl2

Now we can calculate the partial pressure of SO3 when the valve is opened. The volume of the system will be the sum of the volumes of the two cylinders:

Total volume = volume of SO3 cylinder + volume of COCl2 cylinder

Now, we can use the ideal gas law equation to calculate the partial pressure of SO3:

Partial pressure of SO3 = (moles of SO3 / total moles) * total pressure

Let's plug in the values and calculate the partial pressure of SO3.