Linked Questions
12 questions linked to/from Is there a reason for the mathematical form of the equilibrium constant?
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Why does the reaction quotient use the products (multiplications) of reactants and products, rather than their respective sums?
As you may know, the reaction quotient $Q_c$ is defined by the equation
$$
Q_c = \frac{[C]^\gamma [D]^\delta}{[A]^\alpha [B]^\beta}
$$
for the chemical reaction
$$
\alpha A + \beta B \rightarrow \...
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26
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4
answers
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Relation between chemical kinetics and chemical equilibrium
In my chemistry book, the law of chemical equilibrium is derived from the law of mass action:
For a reversible chemical reaction $$\ce{aA +bB\rightleftharpoons cC + dD}$$ where $a$, $b$, $c$ and $d$ ...
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9
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Le Châtelier's Principle and heat
Consider the following reaction at equilibrium.
$$\ce{A->B}, \Delta H < 0 $$
Suppose I increase the temperature. Now, quite a few people would invoke Le Châtelier's Principle and say that since ...
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How to find the empirical formula for an nitrogen oxygen compound from the given mass of nitrogen and the product?
$5.00~\mathrm{g}$ of nitrogen is completely converted into an oxide of nitrogen. The mass of the oxide formed is $19.3~\mathrm{g}$.
The empirical formula of the oxide would be?
My working:
$$\ce{...
- 751
10
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1
answer
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When can I use concentrations instead of activities in equilibrium calculations?
To calculate an equilibrium constant, it is said that you should actually use activities $a_i$ instead of concentrations $c_i$. But it is also said that within a certain range, you can use ...
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2
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Why is the rate of a reaction proportional to the concentrations of reactants raised to their stoichiometric coefficients?
Consider a gaseous state elementary reaction $$\ce{aA(g) + bB(g)} \overset{k_\mathrm{f}}{\underset{k_{\mathrm{b}}}{\ce{<=>}}}\ce{ cC(g) + dD(g)}$$
I know that for this reaction, $$\Delta G = \...
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Why does changing the dilution of an aqueous equilibrium shift the equilibrium?
Say we have the equilibrium $$\ce{A_{(aq)} + 2B_{(aq)} <=> C_{(aq)} + D_{(aq)}}$$ meaning the formula for the equilibrium constant is $$\ce{K_{c} = \frac{[C][D]}{[A][B]^2}}$$ My understanding is ...
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Why are the stoichiometric coefficients used as exponents in the chemical equilibrium constant?
From what I can ascertain, the formulation of the chemical equilibrium constant is somewhat arbitrary. I don't understand the motivation for putting the stoichiometric coefficients in the exponents. ...
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1
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How do we know that rates depend on the product and not the sum of reactant concentrations [closed]
I've been struggling to understand the mathematics behind the calculation in enzyme kinetics within systems biology at an intuitive level.
Every research article and textbook says it is based on the ...
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Confused about underlying reasoning behind reaction quotient/equilibrium constant
I am a high school student taking AP Chemistry. In the unit on chemical equilibrium, there is much emphasis placed on calculating reaction quotients and equilibrium constants using this method: $$aA + ...
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Derivation of equilibrium constant [duplicate]
In general chemistry, we learn that the equilibrium constant, defined in terms of activities, for the reaction
$$\ce{aA + bB -> cD + dD}$$
is given by
$$K_\mathrm{eq} = \frac{(\ce{C})^c(\ce{D})^...
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1
answer
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Rate of a reaction [duplicate]
We know that the rate of a reaction $\ce{aA + bB -> cC + dD}$, the rate of the forward reaction is given by $r_\mathrm f = k_\mathrm f[\ce A]^p[\ce B]^q$ where $ a\neq p$ and $ b\neq q$ according ...
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