Question

Sulfuryl chloride (SO2Cl2) is a colorless liquid that boils at 69°C. Above this temperature, the vapors dissociate into sulfur dioxide and chlorine: SO2Cl2(g) uv SO2(g) 1 Cl2(g) This reaction is slow at 100°C, but it is accelerated by the presence of some FeCl3 (which does not affect the final position of the equilibrium). In an experiment, 3.174 g of SO2Cl2(,) and a small amount of solid FeCl3 are put into an evacuated 1.000-L flask, which is then sealed and heated to 100°C. The total pressure in the flask at that temperature is found to be 1.30 atm.

a) calculate the partial pressure of each of the three gases present.
b) calculate the equilibrium constant at the temperature.

Answer 1

See explanation below for answers

Step-by-step explanation:

First, in order to solve this, we need to write the equation that is taking place:

SO2Cl2 <--------> SO2 + Cl2

WE know that after 69 °C, the SO2Cl2 boils, so all the compounds here are in gaseous state.

Now, let's first calculate the moles of SO2Cl2, (Molar mass of SO2Cl2 is 134.97 g/mol)

n = 3.174 / 134.97 = 0.024 moles

With the moles, let's calculate the innitial pressure of SO2Cl2:

P = nRT/V ---> R = 0.082 L atm / K mol; T = 100 + 273 = 373 K

P = 0.024 * 0.082 * 373 / 1 = 0.734 atm

We know the pressure, so, let's calculate the partial pressure of all the gases. Writting the equation and the innitial condition:

SO2Cl2 <-------> SO2 + Cl2

i: 0.734 0 0

eq: 0.734 - x x x

We know that the total pressure is 1.30 atm, so:

Ptotal = PpSO2Cl2 + PSO2 + PCl2

Replacing the data we have:

1.30 = 0.734 - x + x + x

1.30 = 0.734 - x

x = 1.30 - 0.734

x = 0.566 atm

This means that the partial pressure of each gas is:

PpSO2Cl2 = 0.734 - 0.566 = 0.168 atm

PpCl2 = PSO2 = 0.566 atm

To calculate the equilibrium constant:

Kp = PpCl2 * PpSO2 / PpSO2Cl2

Replacing the data:

Kp = 0.566 * 0.566 / 0.168

Kp = 1.91