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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Metal hydrolysis and equilbrium constants from stability constants
Problem: I want to create minimum solubility plots for a series of metal hydrolysis species against pH (below). But I cannot reconcile literature stability constants and equilibrium constants.
Context:...
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Is the amine nitrogen of methylglycinediacetic acid (MGDA) protonated?
MGDA is a tertiary amine with 3 acetic acid groups. I would like to know whether the amine Nitrogen of MGDA is protonated or not for a given pH value. I could not find any literature data which ...
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Mathematics behind the graph between Gibbs energy and extent of reaction
When the graph between Gibbs energy and extent of reaction is plotted, such a curve is obtained:
I am unable to understand how we got to the concavity of this graph (which can also be seen as the ...
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How to calculate the pH of a mixture of an acid with a buffered solution?
Being a physicist by training, having worked in software development for the last 10 years. Having heard my last chemistry lecture 15 years a go I am a bit lost in regards to how one can calculate the ...
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Products formed on reaction of aqueous solution of iron(III) nitrate nonahydrate
Crystalline iron(III) nitrate nonahydrate, Fe(NO3)3.9H2O, has a very pale violet color. When added to water, the crystals dissolve to form a brown solution. Treatment of this brown solution with ...
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Reaction kinetics exercise for hydrogen iodide synthesis
The rate constant for the reaction of hydrogen with iodine is $\pu{2.45E-4 M-1 s-1}$ at 302 °C and $\pu{0.905 M-1 s-1}$ at 508 °C.
a. calculate the activation energy and Arrhenius preexponential ...
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Do we group reversible reaction with all reactants and product solid as homogenous or heterogeneous equilibrium?
My personal thought is that they should be in heterogenous equilibrium as we define it as all reactants and products being of different phase (phase-their must not be a visible boundary) and solids ...
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Static Equilibrium in an open and closed system
I've had a bit of confusion on whether static equilibrium can exist in an open system.
My textbook states (on modelling static equilibrium through water in a flask):
"Static equilibrium is shown ...
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Acid dissociation constant from conductometric data
$\ce{0.007 M}$ aq. solution of anilinium hydrochloride had molar conductivity equal to $\pu{119.4 S cm2 mol-1}$, which became $\pu{103 S cm2 mol-1}$ when a few drops of aniline were added to the ...
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Why do we say the position of equilibrium is shifted even when K is the same?
I realize that there are similar questions that have already been asked here, however none of them answer the question. The answers all say that (when K is the same) you "you haven't really ...
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metallic mercury is shaken with a solution of mercury(II) nitrate [closed]
Hi there, I am reviewing equilibrium.
About this question, I wonder if the chemical equation is wrong.
Because the description says 'a solution of mercury(I) nitrate is formed'.
However, in the ...
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What side does heat get added on in an equilibrium expression?
I know this is probably such a basic question with fundamental explanations and I can't help from overthinking.
So if we have an equilibrium would the addition of heat as in an increase in temperature ...
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What happens to the ions after dissociation in an aqueous solution? [closed]
I'm in high school studying about Buffer Solutions. We had an example of a solution made up of Ammonium Hydroxide and Ammonium Chloride for a Basic Buffer.
NH4OH ⇌ NH4 (+) + OH(-)
NH4Cl ⇌ NH4 (+) + ...
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Why Michaelis Menten Assumption of equilibrium is necessary to integrate rate of ES production
I read in my textbook that the assumptions of equilibrium and of steady state used by Michaelis and Menten were simplifying assumptions intended to make the following equation one that can be ...
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Is Ksp measured for covalent compounds as well?
A quick search on Google tells me that it is only used for ionic compounds but I think it should be used for some covalent compounds given that some of the covalent compounds also dissociate into ions ...
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How to obtain the expression for residual Gibbs energy?
The property involved is Gibbs free energy, the equations that I wrote are presented in my text book Introduction to chemical engineering thermodynamics by Smith and Van Ness, Chapter 6.
The thing is ...
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How can the Kw of water be constant?
I know in neutral solution, $\ce{[H+]}= \ce{[OH-]}= \pu{1.0 x 10^-7}$.
However, let’s say I add an acid like HCl. This will increase $\ce{[H+]}$, therefore it’s no longer $\pu{1.0 x 10^-7}$, but is ...
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pH calculation of HCOOH +plus HCl solution
Question - What volume of $0.1 \ce{M}$ $\ce{HCl}$ solution should be
added to a $\ce{500 mL}$ of $\ce{0.5 M }$ $\ce{HCOOH }$ solution in
order to prepare an acid solution of $\text{pH}$ =$1.5.$ $K_a$...
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Does it make any sense to graph 1/T versus ln(Kc)?
I calculated $K_c$ experimentally for the reaction $$\ce{CO2 + H2O -> H2CO3}$$ at different temperatures. Because $\Delta G =-RT\ln(K)$, I thought that graphing 1/T against $\ln(K_c)$ would give me ...
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Confusion regarding spontaneous and non-spontaneous reactions
According to Wikipedia: "A chemical reaction is endergonic when non spontaneous. Thus in this type of reaction the Gibbs free energy increases."
My problem with that statement is the wording ...
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Question about computed equilibrium graph
When I was reading a paper about sulfuric acid decomposition,I couldn't understand this graph very well.(link)
The caption says concentration but the vertical axis says mole(not mole/L or something ...
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Higher or lower temperature to produce maximum yield of NH3(g) in Haber process
Question: In order to get the highest yield of NH3(g) in Haber process, should you use high or low temperature?
The answer in the textbook says lower temperature produces more yield of NH3(g) in Haber ...
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Closed pressurized water vessel
Suppose we have a closed container not isolated from the external environment so that heat exchanges can occur on the lateral wall (mainly for convection). The water inside is pressurized by a gas (...
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How to calculate the pH of a solution with addition of a complex
The scenario is this. I have $50$ mL of $0.1$ M $\ce{NH4^+}$ at a certain temperature which gives it a $K_a=5.2\times 10^{-8}$. To this solution, I add $0.02$ moles of $\ce{Cd(NO_3)_2}$. It is known ...
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Does real-world gas phase chemistry use "concentration reaction quotients" (K_c)?
As a theoretical chemist, my entire exposure to reaction quotients and equilibrium constants ($Q$ and $K$) is through thermodynamics ($\Delta G^\ominus = - RT \ln K_{eq}$ and so on).
So as I started ...
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Why doesn't the ocean gradually turn into hydrogen and oxygen gas? [closed]
Maybe I'm wrong about this, but I thought I remembered from high school chemistry that all reactions are in equilibrium. Some equilibria are extremely far to the right or left, so they appear to react ...
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Molar heat capacity of water at equilibrium
Molar heat capacity is defined as the heat energy given to one mole of substance to raise its temperature by 1 degree celcius (or 1 Kelvin)
Mathematically, $$C_{m} = \frac {q}{n\Delta T}$$
Here's a ...
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Would the partial pressure of O2 in the system affect the rate of the decomposition of H2O2?
In my Bio 1 lab we studied the way catalase catalyzes the decomposition of H2O2 and at the end it asked me what conditions would affect the rate of the reaction. It was the type of question that ...
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Understanding Reaction Rates and equilibria
As a high school student grappling with the interplay of reaction rates, Le Chatelier's principle, and equilibria, I have a question about a system that hasn't yet achieved equilibrium.
Specifically, ...
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Equilibrium constant of the formation of ferric thiocyanate
I was reading the paper Relaxation Kinetics of Ferric Thiocyanate (Goodall et. al, 1972) and I came across a passage which read
$\space$ Reaction (1) is the simplest representation of the equilibrium ...
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