Questions tagged [equilibrium]
The state in which both reactants and products are present at concentrations which have no further tendency to change with time.
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Side reaction of I− and acidity of HI
In acidic conditions, I− tends to get oxidised by atmospheric oxygen to give iodine. This is evident in iodine based titration, where upon leaving the setup, blue colour of starch reappears as iodine ...
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Which way Le Chatelier's principle
I have been pondering about the effect of pressure change in regard to Le Chatelier's principle on reactions. For this, I considered the following reaction:
$$\ce{CO(g) + 3H2(g) <=> CH4(g) + H2O(...
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According to PV=nRT,if we increase temp,no of moles will decrease,but no of moles is dependent on mass,mass is constant,then how can moles change?
We know the ideal gas equation is PV=nRT,then, according to this,if we keep Pressure,volume to be constant,then on increasing temperature,no of moles will reduce,this would mean that mass of matter or ...
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How does an equilibrium move when increasing the concentration of water?
I have the following equilibrium given:
$$\ce{[Co(H2O)6]^2+(aq) + 4 Cl-(aq) <=> [CoCl4]^2-(aq) + 6 H2O(l)}$$
(I imagine the (l) for water is wrong, as the water is a part of the solution)
The $\...
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How to make NH3 + H20 favor its products (NH4+ and OH-) [closed]
I am putting together a (fake) proposal for a process that would convert ammonia in cow manure into elemental nitrogen. The first step includes the conversion of that ammonia into ammonium so that it ...
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Explaining Vapour Pressure and Evaporation by Chemical Potential
According to the coexistence curves, both gas and liquid phases can only exist when the chemical potential of both phases are equal.
Does this mean above and below the coexistence curve of liquid and ...
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Effect of inert gas on the rate of reaction
Is there a general effect on the rate of reaction of a dynamic equilibrium when an inert gas is introduced at a constant volume? I know that the position of equilibrium won't change, but much like a ...
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Solutions which Disrupt Equilibrium of Ferric Chloride and Potassium Thiocyanate Reaction
Consider the reaction involving ferric chloride and potassium thiocyanate,
$$\ce{Fe^{3+}(aq) + SCN-(aq) <=> FeSCN^{2+}(aq) }$$
,where $Cl^-(aq)$ and $K^+(aq)$ are spectators. Here's my thinking ...
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How to shift SO3/SO2 equilibrium?
I am struggling with a chemical equilibrium question and would appreciate some help. The question involves a closed system where the equilibrium
$$\ce{2SO2(g) + O2(g) <=> 2SO3(g)}$$
has been ...
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What is the vapor pressure when the vapor and some inert gas is in a sealed steel container?
Suppose that there are two chemical species in a sealed container(1L). X(l) is in phase equilibrium with X(g). The another one is Helium gas, which is 2 atm. If the vapor pressure of X at the given ...
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Confused about underlying reasoning behind reaction quotient/equilibrium constant
I am a high school student taking AP Chemistry. In the unit on chemical equilibrium, there is much emphasis placed on calculating reaction quotients and equilibrium constants using this method: $$aA + ...
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Why change of gibbs energy per mole is zero at equilibrium?
I was reviewing this concept and thought of this: $\frac{dG}{dt} = \frac{\partial G}{\partial \xi}\frac{d \xi}{d t}$, for a reaction to be at equilibrium $\frac{d G}{d t}$ must be zero but I have ...
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Strange behavior of equilibrium constant when most of the components are solids / pure liquids
Consider the reaction $\alpha A(g) + \beta B(s) +\gamma C(s) +\cdots \rightleftharpoons \delta D(s)+\epsilon E(s)+\cdots $, so the chemical equilibrium constant should be $\dfrac{1}{[A]^\alpha}$, ...
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How do the coefficients in an equilibrium question affect the shifts in position of equilibrium?
Let's say I have this equation:
$$A_{(g)}\leftrightharpoons 2B_{(g)}$$
According to Le Chatelier's principle, if I decrease the pressure, then more of B will be made in order to increase the pressure ...
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pH and degree of dissociation of drugs
I have a doubt, i hope not so stupid.
Suppose we consider a buffer solution of acetic acid/acetate at pH = pKa = 4.76 and we add aspirin (pKa = 3.5): given that the pH of the solution is higher than ...
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Calculating the percentage of dissociation degree
The question is as such:
Notice the equilibrium expression. $$K_c=\frac{[NH_3]^2}{[N_2][H_2]^3}.$$ Initially, there were $0.28$ moles for each reactant, after it reaches equilibrium, the number mol ...
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According to Le Chatelier's principle, is it possible to fully consume a reactant if we increase the concentration of the other reactant(s)?
Suppose there is a hypothetical chemical equation: $$\ce{ A + B <=> C}$$
If we increase the concentration of B to a large extent with the intention of fully consuming A in the reaction, will A ...
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Calculate the pH at the equilibrium point in an acetic acid sodium hydroxide titration
You perform a titration of $\ce{CH3COOH}$ with $\ce{NaOH}$. Let the original concentration of acetic acid be $\pu{0.2 M}$. The volumes of $\ce{CH3COOH}$ and $\ce{NaOH}$ are the same. Then the ...
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Unit of equilibrium constant in formula for Gibbs free energy change at arbitrary temperature
We know the relation for Gibbs free energy change of a reaction at any stage and any temperature
$$\Delta G=\Delta G^{\circ}+RT\ln Q$$
where Q is reaction quotient. Subsequently, we get the rate ...
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Why is the theoretical value of the electrode potential different to the experimental value for Cu and Al for a galvanic cell by using Nernst equation
I've construct a galvanic cell with the Al strip putting in the Aluminum nitrate solution and Cu strip putting in the CuSO4 solution. KNO3 is used as the salt bridge in this experiment. The question ...
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Calculating equilibrium constant for a general acid base reaction
I am trying to find the equilibrium value for different acid-base reactions. I have understood that when an acid and base are in an aqueous solution, many different reactions will occur. By combining ...
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how to neutralize stannous chloride (50ml) to make it safe for disposal
I made a small quantity of stannous chloride by dissolving tin in muriatic acid - I would like to neutralize it for safe disposal - will mixing it with soda bicarbonate dissolved in water accomplish ...
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On Le Chatelier's principle
According to my textbook,
Increasing the concentration of the reactants increases the rate of forward reaction only to reestablish equilibrium (Le Chatelier's principle)
But doesn't that also ...
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Calculating simulatenous equilibrium concentrations given dissociation constants
Reactants A, B, and C form the complexes AB and BC according to:
$$ AB \rightleftharpoons A + B, \quad BC\rightleftharpoons B + C $$
Each reaction has a dissociation constant, $K_{dA}$ and $K_{dC}$, ...
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How can I systematically solve a system of non-linear equations using a standard graphing calculator?
In analytical chemistry, when we have to consider more than one equilibrium, the problem can be reduced to solving a system of non-linear simultaneous equations by applying the mass and charge balance ...
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Equilibrium concentrations of CO and Cl2 by dissociation of phosgene
I am working through a problem set from MIT's open courseware course Principles of Chemical Science.
The question is:
Phosgene $\ce{(COCl2)}$ is a chemical warfare agent that decomposes by the ...
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Why does the reaction of dissolution stop at an equilibrium point? [closed]
The formula for Gibbs free energy is $\Delta G=\Delta H-T\Delta S$.
If Gibbs free energy is negative, the reaction is spontaneous. This also applies to dissolution reactions.
However, we know that ...
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Does temperature affect ionic strength?
Hello I apologize if this is a dumb question but if I have a phosphate buffer made up of Na2HPO4 and NaH2PO4 and I gradually increase the temperature (lets say 10,20,30,40,50) what would happen to the ...
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Why can't the product of an acid reacting with water react with water itself and produce OH-?
Why can't the product of an acid reacting with water react with water and produce $\ce{OH-}$?
Take the reaction below as an example:
$$\ce{H2CO3(aq) + H2O(l) <=> HCO3-(aq) + H3O+(aq)}$$
$$\ce{...
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Equilibrium Constant: G vs. Go [duplicate]
I'm reading Clayden's Organic Chemistry textbook and in Chapter 12 on equilibrium he writes:
I am confused by the usage of $\Delta G$ as opposed to $\Delta G^\circ$. Isn't the equilibrium constant ...
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