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A Level Chemistry - Kc Calculations

Could someone help me with the answer to this please?
I've done it quite simply which probably means what I have done is wrong!

Calculate Kc for the following equilibrium at a particular temperature, given the results of an analysis of the equilibrium mixture which show that the concentration of SO2 = 0.23, O2 = 1.37, and SO3 = 0.92 mol dm-3.

Reply 1

TSR Jessica

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Reply 2

charco

Study Forum Helper

Original post by emfrostyy

No, it's simple.

Put the values into the equilibrium expression corresponding to the equation for the reaction.

Reply 3

Notthemainguy

I got 11.67 which looks wrong but ...

Reply 4

charco

Study Forum Helper

Original post by Notthemainguy

I got 11.67 which looks wrong but ...

Why does it "look" wrong ...

... just curious, like.

Reply 5

Notthemainguy

I'm not used to seeing kc that ...big usually its less than 1

Reply 6

charco

Study Forum Helper

Original post by Notthemainguy

I'm not used to seeing kc that ...big usually its less than 1

Equilibrium constants can range from 0 to infinity.

You can look at an equilibrium from either direction, if kc is very small in one direction it must be very large in the reverse direction.

The equilibrium constant for hydrolysis of an ester is about 4 then the constant for the esterification reaction is 0.25 (for example)

k_forward = 1/k_back

(edited 7 years ago)

Reply 7

Notthemainguy

Oh because you'd get the reciprocal of the quotient