QUICK EQUALIBRIUM QUESTION PLEASE HELP

[matt123]

 For the equilibrium
H2(g) + CO2(g) H2O(g) + CO(g)
Kc = 3.18 at 1106K. If each of the four species was initially present at a concentration of 3.000M, calculate the equilibrium concentration of the CO(g) at this temperature
 

0.844
3.268
3.844
3.460
2.156

please help , exams coming up and i really want to get my head around how to do these questions.
MANY THANKS IN ADVANCED ,

[matt123]

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[matt123]

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[VivaTequila]

Never seen this :s

Do we need to know this for midyears? We are still on chap 14 of Heinemann and I thought we were going fast...

[Mao]

@Viva, he's not in VCE.

@matt, stop self-bumping please.

Let 'x' be the change in concentration of CO (from the initial 3.0M) after the system is allowed to isothermally reach equilibrium. At equilibrium, Q=K, [CO] = 3 + x, [H2O] = 3+x, [H2] = 3-x, [CO2] = 3-x



solve for x, then find [CO] = 3+x as the correct answer.

[matt123]

@Viva, he's not in VCE.

@matt, stop self-bumping please.

Let 'x' be the change in concentration of CO (from the initial 3.0M) after the system is allowed to isothermally reach equilibrium. At equilibrium, Q=K, [CO] = 3 + x, [H2O] = 3+x, [H2] = 3-x, [CO2] = 3-x



solve for x, then find [CO] = 3+x as the correct answer.

thanks so much , makes sense now
appreciate it Mao