[hiiamhere]

At high temperature, HCL and O₂ react to give CL₂ gas:
4 HCL_(g)+O_2(g)<-->2CL_2(g)+2 H₂O_(g).
If HCL at 2.30 bar and O₂ at 1 bar react at 750k, the equilibrium pressure of CL₂ is measured to be 0.93 bar. Determine the value of K_eq at 750k.

Im totally lost here. At first I thought it was asking for an equation, i.e, k=reactants/products, but im sure thats wrong. I find this question unfair because we haven't gone over bar pressure or anything related to this type of question.

[Yggdrasil]

Bar is a unit of pressure equal to 10⁵ Pa.  It is a convenient unit of pressure because it is derived from SI units and atmospheric pressure is about 1.013 bar.  To convert bars to other units of pressure see below:

http://en.wikipedia.org/wiki/Bar_%28unit%29

My hints for this problem:
1)  Write the expression for K_eq for this reaction (note: are you looking for K_p or K_c?)
2)  Find the final concentrations/pressures of all of the gases at equilibrium using stoichiometry (e.g. if 0.93 bar of Cl₂ is produced, how much HCl was used?)
3) Plug these values into the expression for K in #1.

Another useful hint:  Chlorine is Cl not CL.  All elements whose symbol consists of two letters have a lower case letter for the second letter in their symbol.  This way chemists can tell the difference between CO (carbon monoxide) and Co (cobalt).

[hiiamhere]

ok, I think I got it. Thanks for the help.
yeah, CL was a typo, I meant Cl.

[AWK]

It seems something is wrong. In closed system these should be partial pressures (sum will be 3.3 bar, and never in this case, after reaction the final pressure can be 0.93 bar)