edexcel- "quotient"? - unit 4 Watch

sandra
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In topic 4.3 (chemical equilibria), theres somethings mentioned about a “quotient”

For example : “if the quotient does not equal Kc, the system is not at equlilibrium and will react until it reaches equilibrium when there will b no further change in any of the concentrations.”
And
“A change in the conc of one of the substances in the equilibrium mixture will not alter the value of K but will alter the value of the quotient
I cudnt find anything about a “quotient“ in my textbk- so I really don’t know what they r talking about

Cud someone plz explain to me what this quotient is that they r talking about , and how do we find it out?

thanks
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charco
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quotient just means the half of the equatino in the equilibrium law that equals kc when at equilibrium. ie. it is the division sum of product concentrations raised to the powers of their stoichiometries divided by the reactant concentrations raised to the powers of their stoichiometries.
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sandra
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(Original post by charco)
quotient just means the half of the equatino in the equilibrium law that equals kc when at equilibrium]. ie. it is the division sum of product concentrations raised to the powers of their stoichiometries divided by the reactant concentrations raised to the powers of their stoichiometries.


sorry , i still dont understand

cud u mayb explain by showing me the equation or something? and then highlighting what the quotient is?
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oxymoron
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(Original post by sandra)


sorry , i still dont understand

cud u mayb explain by showing me the equation or something? and then highlighting what the quotient is?
Example:

A + 2B ---> C


Kc = [C]/[A][B]^2 (when all concentrations are at equilibrium)

However, when the system is not at equilibrium, the quotient is still equal to the same thing:

Quotient = [C]/[A][B]^2 ... but note this is only equal to Kc when the system is at equilibrium.

Is that any clearer?
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sandra
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(Original post by oxymoron)
Example:

A + 2B ---> C


Kc = [C]/[A][B]^2 (when all concentrations are at equilibrium)

However, when the system is not at equilibrium, the quotient is still equal to the same thing:

Quotient = [C]/[A][B]^2 ... but note this is only equal to Kc when the system is at equilibrium.

Is that any clearer?
so, basically, Kc = quotient = [C]/[A][B]^2 but when the system is not in equilibrium, then, quotient is not equal to Kc ??
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sandra
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i think ive understood - thanks oxymoron

and thanks to charco as well!
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