[Dallon]

This might seem a little rediculous to some but I simply can't do this question. Im in Chem 111 (part 2) -first year chem distance ed course and the textbook that was made by this guy is useless in helping me.

The question is:
For the reaction
 H₂(g)+CO₂(g) ::equil::CO(g)+H₂O(g)

K_c=0.771 at 750 degrees C. Find the resulting concentrations of the H₂ and H₂O gases when 1.00 mol of H₂ and 1.00 Mol of CO₂ are placed in a 5.00 L container and permitted to reach equilibrium.
(How do I find these concentrations when there are 2 unknown variables)

Also if someone could suggest a good place to get a full overview on barely soluble ionic solids and Fractional Precipitation reactions that'd be great. I'm learning this course basically from youtube and it only goes so far.

[Borek]

These two unknowns are related by the reaction stoichiometry.

How many moles of H₂O are produced per each mole of CO?

[Dallon]

One- They're both 1 to 1 moles- I actually did the equation by using the ICE table and got an annsweer but i dont know if it is right- Here's what I did- ( if i did it right ill know what to do for the next one).

  H₂    +                     CO₂                            CO+              H₂O
I   (0.2M)                     (0.2M)                      (nothing)   (nothing)

C     -X                         -X                               +X            +X

E    (0.2-x)                  (0.2 -x)                            X              X



and then with this info i got


Kc(which is 0.771)= (X)²/ (0.2-X)²

which i got to be Sqrt 0.771 = X/( 0.2-X)
and the Sqrt of 0.771 = 0.878

0.878*(0.2-X)=(1.765X10^-1-0.878X)
which is equal to X²

X=9.35X10^-2

and therefore CO and H₂O equal 9.35X10^-2


did i get this right? or where did i go wrong

[Borek]

Looks OK to me. I didn't check the numbers, just the approach.