can't understand the equilibrium constant Kc

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pondering-soul
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So in the reaction between ethanol and ethanoic to produce ethyl ethanoate, my textbook says you form an equilibrium mixture with all the components. I understand this part, you can also then titrate the mixture to get amount of moles of ethanoic acid and from this mol of the rest of the components.

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what does the equation mean? the number of moles of ethyl ethanoate and water divided by moles of ethanoic acid and ethanol gives a constant? what does the small x and y represent? the expression makes no sense to me

thanks for any help in advance
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ALikesGeetars
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Basically for Kc, the way the equation is structured out is that it is Products/ Reactants (The Products divided by the reactants) which is why the Ethyl Ethanoate and Water are on the top of the first equation. Now the reason why there is a small x and y is to do with something called the Order. The large X and Y are for the concentrations of the product or reactant which you then multiply to the power of the order. For example, if it is a first order reaction and we assume the concentration at EQM of X is 2.0 then we would write, [2.0}^1, and if it was a second order reaction [2.0]^2, then you bung it all into a calculator to find the Kc Value.
Hope this helps
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Pigster
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(Original post by ALikesGeetars)
Basically for Kc, the way the equation is structured out is that it is Products/ Reactants (The Products divided by the reactants) which is why the Ethyl Ethanoate and Water are on the top of the first equation. Now the reason why there is a small x and y is to do with something called the Order. The large X and Y are for the concentrations of the product or reactant which you then multiply to the power of the order. For example, if it is a first order reaction and we assume the concentration at EQM of X is 2.0 then we would write, [2.0}^1, and if it was a second order reaction [2.0]^2, then you bung it all into a calculator to find the Kc Value.
Hope this helps
Unfortunately, you have got yourself confused between rates and equilibria.

The exponents x, y etc. are not the orders WRT each chemical in the equilibria.

The exponents x, y etc. are the values for the molar ratios in the balanced equation.

For example: the Haber process. N2 + 3H2 <-> 2NH3

Kc = [NH3]2 / [N2] [H2]3

Note, the ^2 and ^3 are the same as the 2 and 3 in the balanced equation.
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ALikesGeetars
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(Original post by Pigster)
Unfortunately, you have got yourself confused between rates and equilibria.

The exponents x, y etc. are not the orders WRT each chemical in the equilibria.

The exponents x, y etc. are the values for the molar ratios in the balanced equation.

For example: the Haber process. N2 + 3H2 <-> 2NH3

Kc = [NH3]2 / [N2] [H2]3

Note, the ^2 and ^3 are the same as the 2 and 3 in the balanced equation.
Oh shoot you're right! I should've thought about it more carefully! Thanks
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