Thread: Please Help -- I have a test tomorrow (chemistery)

I need urgent help on this chem problem.

i have a test tomorrow and a question like this is coming and i hav NO idea plszzz

2H20 + 2SO2 <--> 2H2S + 3O2

Initial concentrations:

H20 = 2.8M
SO2 = 2.6M


Kc = 1.3 x 10 ^ (-6)

They want me to find the concentration of H2S at equilibrium??

please help

Originally Posted by NeedHelp18

I need urgent help on this chem problem.

i have a test tomorrow and a question like this is coming and i hav NO idea plszzz

2H20 + 2SO2 <--> 2H2S + 3O2

Initial concentrations:

H20 = 2.8M
SO2 = 2.6M


Kc = 1.3 x 10 ^ (-6)


They want me to find the concentration of H2S at equilibrium??

please help

let x be the amount which was converted into products from each reactant.
H2O= 2.8-x, SO2= 2.6-x, H2S= x, O2= x/2 * 3

Ksp= /

Plug in the value and find the value of x

you have to arrange all the aqueous species into an equilibrium constant expression. (concentrations of products over the concentrations of reactants) You haven't stated the physical states of the species involved so I'll have to leave that step up to you Then you just put in the concentrations you have and it will give you the concentration at equilibrium.

In general: pP + qQ > rR + sS
(R)^r x (S)^s / (P)^p x (S)^s = K
which means if you have any coefficients in front of the species you raise the concentration to that coefficient value. I hope this helps...if it's too muddled an explanation I'm really sorry Good luck in your test!!!