Question

2 moles of so2 and 1 mole o2 are heated the reaction proceeds and equilibrium is reached when 80% of so2 is changed to so3 if the initial pressure is 30 bar the equilibrium pressure is

Answer 1

Answer:

Here's another way to do it. Your reaction was:

2SO3(g)⇌2SO2(g)+O2(g)

Since you have a constant volume, and since the temperature is assumed constant as well (as you are not given two temperatures), you can expect that the change in mols of gas relates mainly with the change in pressure, meaning that

P=P1+P2+..., Dalton's Law of Partial Pressures,

applies, and the given equilibrium pressure is the total pressure of all gases in the mixture.

Filling out an ICE Table gives:

2SO3(g)⇌2SO2(g) + O2(g)

I 300 torr 150 torr 0 torr

C -2x torr +2x torr +x torr

E 300-2x torr 150+2x torr x torr

Remember that the change in pressure will include the stoichiometric coefficients in front of the molecule in the balanced reaction.

But since you know that the equilibrium pressure was 550 torr, you can use Dalton's law of partial pressures:

P=(300−2x)+(150+2x)+x=550

P=450+x=550

x=100 torr

That gives you each equilibrium partial pressure as:

PSO3=300−2(100)=100 torr

PSO2=150+2(100)=350 torr

PO2=100 torr

Note that if you get a negative pressure, it means you mixed up the partial pressures of SO2 and SO3. if you don't get the right KP, it may also be because your stoichiometric coefficients weren't incorporated into the KP expression.

The KP is then:

Answer 2

Answer:

20 bar..............right answer