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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How to calculate the concentration of all relevant species in a buffer of a given pH?

You prepare $1.0~\mathrm{L}$ of a $0.25~\mathrm{M}$ acetic acid solution with a final $\ce{pH}$ of $6.0$. What are the molar concentrations of all relevant acetic acid species ($[\ce{HA}]$ and ...
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2answers
34 views

What are the effects of adding water to a system at equilibrium?

Given the reaction $\ce{NaCl~(s) <=> Na+~(aq) + Cl^{-}~(aq)}$. $\ce{NaCl}$ is added to water and equilibrium is reached. Does the reaction shift to the left/right/not shift at all if more ...
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79 views

reference states for activities

I wanted to ask clarifications about a passage in Atkin's physical chemistry book, chapter 9, in the paragraph 9.2 description of equilibrium. For studying equilibrium of a reaction, where $\nu_i$ ...
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1answer
23 views

Should the liquid be included in Kc expression?

Should the concentration of liquid water be included in the Kc expression for the following reaction: $$\ce{2 NO2{(g)} + 7 H2{(g)} \rightarrow 2 NH3{(g)} + 4 H2O{(l)}}$$ if water is liquid and all the ...
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2answers
40 views

Dynamic equilibrium - effect of adding inert gas [duplicate]

Well consider the reaction $A + B ⇌ C$ Adding inert gas to a container where this reaction is taking place will increase the pressure of the system. In accordance with Le Chatelier's Principle, the ...
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3answers
62 views

Thought Experiment on Boiling

In this thought experiment, let’s consider the surrounding to be air that is composed of entirely water vapor (no other species like $\ce{O2}$ and $\ce{N2}$ are present). The surrounding is infinitely ...
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1answer
45 views

Why is it possible, that an equilibrium shifts?

So in class, I've learned about Equilibrium. So it is basically when the rate of the reverse and the forward reaction are the same. So I was like that sounds pretty easy, I can understand this. And ...
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57 views

How to find and use the Clausius-Clapeyron equation

I know how to get the equation from the Clapeyron equation but I have a question regarding a the integration along a phase boundary and a small step in the derivation that I will make clear when I ...
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1answer
39 views

Acid dissociation constant and equilibrium constant

What is the relationship between acid dissociation constant and equilibrium constant for an acid's reaction with water? If we have this reaction: $\ce{CH3COOH + H2O → CH3COO- + H3O+}$ I would ...
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48 views

Why do acids usually completely react with bases?

When a neutralisation reaction happens, for example, $ 100 \mathrm{mol.l}^{-1}$ of $\ce{HCl }$ with $\mathrm{100 mol.l}^{-1}$ $\ce{NH_3}$, why does all of the base and acid get converted to salt ? Why ...
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24 views

Equilibrium Constant of a Salt knowing the solubility

Calculate the equilibrium constant in $\ce\\M ^ 3$ of the heterogeneous system in aqueous solution: $\ce{CaF2 \leftrightarrows Ca^{2+} + 2F-}$ Knowing that the solubility of the salt is $15.9 ...
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38 views

Why does the ionic product of water remain constant after addition of non-neutral solute?

In my textbook, it is given that the ionic product of water $K_w$ remains constant even when a non-neutral solute such as an acid is added to it. $$K_w=\ce{[H3+O][OH- ]}$$ When a strong acid is added ...
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24 views

The effect of concentration on the equilibrium constant [duplicate]

I read in my chemistry textbook that a change in concentration does not affect the equilibrium constant (Kc). All my book states is that a change in concentration will shift the equilibrium to ...
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0answers
17 views

Reaction Rates & Eqiulibrium [duplicate]

So I have a quick question about some concept I have watched in a video, it is illustrated as follows. $$\ce{A + B <=> C + D}$$ So what the video is saying is that if you increase $\ce{A}$ ...
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1answer
42 views

Neutralizing sulfur-like smells in car

A full bottle of jewelry cleaning (links product and material safety data sheet below) broke in my car and went unnoticed for a few days. Now the car has a sulfur-like smell whenever I go into the ...
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2answers
109 views

Predict the standard potential at 310 K for the cell constructed from the hydrogen electrode and metal-insoluble salt electrode

I've run into trouble on this question Predict the standard potential at 310 K for the cell constructed from the hydrogen electrode and metal-insoluble salt electrode $\ce{Ag(s)|AgCl(s)|Cl-}$. ...
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1answer
30 views

Stuck with derivation of the integrated rate equation for a pseudo first order equilibrium reaction

I was reading about the integrated rate law. However I have problems to follow the solution. I have an equilibrium reaction: [A]+[B]=[AB] with forward and back reaction. I approximate the ...
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1answer
55 views

Where does this equation for the activity in the gas phase equilibrium between N2, H2 and NH3 come from?

I have a question with Equilibrium Constant. I understand that for a reaction in equilibrium $aA +bB \rightleftharpoons cC +dD$ $$K_c= \frac{[C]^c[D]^d}{[A]^a[B]^b}$$ and $K_p$ is just using the ...
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255 views

What is the difference between “reaction in both directions” and “equilibrium”?

According to the Wikipedia page on Chemical Equations: Symbols are used to differentiate between different types of reactions. To denote the type of reaction: "$=$" symbol is used to denote a ...
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2answers
38 views

Is this reaction at equilibrium?

The following equilibrium occurs: $$\ce{2 NOCl(g) <=> 2 NO(g) + Cl2(g)}$$ A gaseous mixture of $\ce{NOCl}$, $\ce{NO}$ and $\ce{Cl2}$ is put in a container. After a few minutes it is found that ...
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1answer
30 views

In the following reaction, will the ratio between substances be 3:1?

In the reaction $$\ce{3 C2H2(g) <=> C6H6(g)}$$ will the ratio of $\ce{[C2H2(g)]}$ to $\ce{[C6H6(g)]}$ at equilibrium be 3:1? How is the mole ratio related to the equilibrium (or lack thereof) ...
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1answer
48 views

Which has a greater entropy?

Which of the following has greater entropy? a. $\ce{CH3COOH~ (aq)}$ or b. $\ce{CH3COO^{-}~ (aq) + H+~(aq)}$ They are both in the same state, and have the same number of particles.. so how do ...
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41 views

Will room-temperature water in a sealed flask evaporate?

Some liquid water is present inside a sealed flask at room temperature. Is water evaporating, and is the system at equilibrium? First of all, can water evaporate in a sealed flask at room temperature? ...
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41 views

Can there be more than one combination of reactant/product concentration for a specific equilibrium constant?

For an elementary reaction like $$\ce{A + B -> AB},$$ $$K_{c} = \frac{\ce{[AB]}}{\ce{[A][B]}}$$ and $$\frac{\mathrm{d}\ce{[AB]}}{\mathrm{d}t} = k\ce{[A][B]}.$$ If I let the reaction reach ...
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13 views

Exothermic reactions at high temperature and the chemical equilibrium

Why are many exothermic reactions, like Haber process, conducted at high temperature, thus their unfavourable equilibrium position?
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27 views

Trouble to predict the effect of pressure and temperature for a reaction in equilibrium

I have trouble to predict the effect of decreasing pressure and increasing temperature on the reaction $\ce{N2 + 2O2 <=> 2NO2}$. Increasing temperature caused this reaction to shift in the ...
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1answer
52 views

Why is CO a major species only in fuel-rich combustion?

In fuel-rich combustion, my understanding is that enough fuel reacts and consumes all of the oxygen present. The combustion products $\ce{CO2}$ and $\ce{H2O}$ undergo dissociation until equilibrium is ...
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1answer
32 views

Why do strong acids dissociate (almost) fully on a molecular level?

In the Brønsted-Lowry theory, strong acids $\ce{HA}$ dissociate using water and react into hydronium ions and the conjugate bases $\ce{A-}$. However I never understood in the strong acids case what ...
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2answers
31 views

Balancing Ionic and Net Ionic equations

I am currently taking a chemistry course about acids and bases. One of the things I am a bit confused about, is the acid and base neutralization reaction, and how to balance it. For Example: ...
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69 views

If the equilibrium constant in a reaction is greater than 1 is it possible that there are more moles of reactants than products?

I'm wondering if this is possible because could there not be a situation in which the reactants were pure solids/liquids and would therefore not contribute to the value of k but still contain more ...
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2answers
98 views

Can Ketones next to a Nitrogen hetero atom tautomerise?

I worry that the electronegative N will stabilise keto form so much that equilibrium will be so far towards keto it would be unreasonable to call the enolisiation process a factor
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72 views

Redox Question: Concentration of Pb2+ is unknown

What is the concentration of $\ce{Pb^{2+}}$ in a lake that has a pH of 6.0 and is in equilibrium with $\ce{PbO2(s)}$ and atmospheric oxygen? $\ce{PbO2(s) +4H+ +2e- -> Pb2+ +2H2O}$ log K = 49.2 ...
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100 views

Filling a buret tip before an experiment

I have a question that asks if the buret tip is not filled before the experiment what would happen (effect on molarity for acid/base titration). The way I'm thinking about it, it's not like you're ...
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1answer
32 views

can i calculate equilibrium constant of this reaction?

Good day, i had organic chemistry labs. And we had this reaction: $$\ce{(CH3)3COH + HCl -> (CH3)3CCl + H2O}$$ My question is: how do i explain my yield of reaction is only 40%? My theory is: ...
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How do I calculate equilibrium partial pressures of $\ce{H2}$, $\ce{N2}$, and $\ce{H2O}$ and $K_{eq}$ for this problem?

This is the complete problem: A mixture of $0.10$ mol of $\ce{NO}$, $0.050$ mol of $\ce{H2}$, and $0.10$ mol of $\ce{H2O}$ is placed in a $1.0$ L vessel at $300$ K. The following equilibrium is ...
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1answer
25 views

Is it possible to normalize the concentration equilibrium constant between different reactions for comparison?

A follow up question from this answer: Compare: $\ce{A(aq) +B(aq)->AB(aq)}$ $\ce{2A(aq) +B(aq)->A2B(aq)}$ We have two similar reactions but the equilibrium constants can vary by a ...
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1answer
49 views

Does Combining Solid/Liquid Concentration with $K_c$ Matter when Comparing $K_c$ of Different Reactions?

I know it is convention to take liquid/solid concentrations as constants and lump it with the equilibrium constant. However, if we were trying to compare the equilibrium constants of two different ...
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1answer
53 views

In a reaction if the equilibrium constant K was infinity, could you produce an infinite number of products at equilibrium?

It's impossible to produce an infinite amount products if the k constant was infinity? no right?
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56 views

Finding initial pressure in a chemical equilibrium

Consider the equilibrium below. If $K = 4$ and initial pressures of $\ce{CO}$ and $\ce{H2O}$ are equal, giving a total pressure of $1.5~\mathrm{bar}$ at equilibrium. What was the initial pressure of ...
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230 views

Effect of addition of inert gas in reaction at equilibrium

Can anyone please explain dissociation reaction increases with the addition of an inert gas? I am still new to the topic equilibrium so please explain in simple words.
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35 views

Effect of temperature on equilibrium

Why is exothermic reactions are favoured by low temperature while endothermic reactions are favoured by high temperature?
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45 views

Equilibrium constant and reaction Quotient

does reaction quotient After equilibrium has been achieved make any sense? At equilibrium point rates of forward and backward reaction are same and the system is in dynamic equilibrium.The graph of ...
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56 views

Are there actually any reactions during which STATIC equilibrium is reached, as opposed to dynamic?

Static would be where a set amount of both products and reactants is formed. Dynamic would be where both the forward and backward reactions occur at equal rates, meaning no change in the overall ...
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60 views

Why is equilibrium achieved at different stages of a reaction?

In other words, I want to know why some reactions attain equilibrium early in the reaction while some reactions obtain equilibrium at the end of the reaction. Why is this the case?
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26 views

Actual meaning of equilibrium

What is actually meant by that concentration of reactants and products remain constant in equilibrium?
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92 views

Buffer action of borax

How does a mixture of borax and boric acid act as an acidic buffer? Please also describe the mechanism of its buffer action.
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How can a protein folding transition state have zero lifetime?

I'm doing a module on my Biochemistry course looking at protein folding, and in a discussion of [folding] transition states I was a little confused at the thought of a zero-lifetime transition state - ...
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2answers
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Can assumptions made during calculation of ka of buffer solutions be justified?

We make many assumptions in sciences which are not always true but as they make little difference we ignore them for simplicity. But today I have decided that I can no longer be lured into using ...
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How do you calculate the proportion of ammonia produced from different pressures in the Haber process using the equilibrium equation?

I tried to write a increase in pressure to twice as much like this: $$\frac{2(x+1)^2}{(0.5-0.5x)2(1.5-1.5x)^3}=K$$
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41 views

Finding the equilibrium constant Kₚ, when temperature is given

At $1000~\mathrm{K}$, $K_p = 1.85$ for the reaction. $$\ce{SO_2 + \frac{1}{2}O_2 <=> SO_3}$$ What is the value of $K_p$ for the reaction $$\ce{SO_3 <=> SO_2 + ...