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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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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10 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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24 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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1answer
13 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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28 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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1answer
10 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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9 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 $N_2 +O_2 = NO_2$. Increasing temperature caused this reaction to shift in the forward direction ...
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11 views

Electrochemical Equilibrium with molar mass [on hold]

The electrochemical cell described by the cell notation has an $\mathrm{E^o\ of\ 0.10 V}$. Calculate the maximum electrical work (kJ) the cell has done if $\mathrm{157.41 g}$ of $\ce{H+(aq)}$ (Molar ...
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1answer
43 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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22 views

How do I get the solubility from the solubility product? [closed]

The solubility product, $\mathrm{K_{sp}}$, of iron(III) hydroxide is $4 \cdot 10 ^{-38}$ at $\mathrm{25 ^\circ C}$. Calculate the solubility of $\ce{Fe(OH)3}$ in $\mathrm{mol/L}$
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17 views

How do I find the concentration of HF in the equilibrium system under the conditions listed below? [closed]

The equilibrium constant for the reaction H2(g) + F2(g) <===> 2HF(g) has the value 2.1 x 10 ^3 at a particular temperature, the concentrations of both H2 and F2 are found to be 0.0021 M. What is ...
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1answer
28 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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12 views

Will the 'equilibrium constant' of ionic liquid phase reaction remain constant at constant temperature? [closed]

In an aqueous electrolyte reacting system, based on the definition of equilibrium constant as the ratio of activities of products to reactants, can we state that: (1) equilibrium constant at ...
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2answers
28 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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61 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
76 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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1answer
67 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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3answers
60 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
29 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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1answer
25 views

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
15 views

Is it possible to normalize $K_c$ 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
40 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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36 views

How do I calculate the molar mass of an unknown gas?

A piston is placed in a closed tube. To the left, there is Hydrogen Gas at 400K and 4 atm. To the right, there is an unknown gas at 200K and 2 atm. At equilibrium, the piston is at 1/3 of the length ...
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42 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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48 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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53 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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2answers
27 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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39 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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50 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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2answers
50 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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23 views

Actual meaning of equilibrium

What is actually meant by that concentration of reactants and products remain constant in equilibrium?
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72 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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124 views

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
62 views

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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13 views

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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37 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 + ...
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1answer
40 views

Why is the water column empty in ICE table

In the ICE table pure solids and liquids have a value of one in the equilibrium expression but when we create an ICE table, why is the $\ce{H_{2}O}$ column empty? Should it not have a value of one?
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595 views

Determining if reaction is endothermic or exothermic using equilbrium constant

For the following reaction: $$W_{(s)}+4\,Br_{(g)}\rightleftharpoons WBr_{4(g)}$$ At 900 K, $K_{p}=100$ and at 2800 K, $K_{p}=5$. At higher temperatures, the equilibrium has shifted towards the ...
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1answer
76 views

Applying the Le chateliers principle

I am an issue understanding the changes that take place when we decrease the pressure of a reaction. I have understood that when we increase the pressure the side having more number of moles wants ...
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1answer
34 views

Where can I find Equilibrium Constants?

When trying to develop mathematical models to show the concentration in a reaction, where can one find a database or good source of known equilibrium constants if it is not necessarily very convenient ...
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1answer
68 views

Why is the equilibrium constant given in litre per mole?

At $800\:\mathrm{K}$ a reaction mixture contained $0.5\:\mathrm{mol}$ of $\ce{SO2}$, $0.12\:\mathrm{mol}$ of $\ce{O2}$ and $5\:\mathrm{mol}$ of $\ce{SO3}$ at equilibrium. $K_c$ for the equilibrium ...
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50 views

Name the equation $\Delta G=\Delta G^{\circ}+RT \ln Q$

As the title states, what is the name of the equation $$\Delta G=\Delta G^{\circ}+RT \ln Q$$ My textbook does not explicitly state the name and I could not find anything on google.
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1answer
47 views

Determining vapor pressure from equilibrium constant

The reaction is $$CoCl_{2(s)}+6\,H_{2}O_{(g)}\rightleftarrows [Co(H_{2}O)_{6}]Cl_{2(s)}$$ Note that the reaction is at equilibrium. I have determined the value of $K_{p}=5.5\times10^{12}$. The next ...
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1answer
35 views

What does (heated) mean in a chemical equation?

I'm supposed to balance the following equation: $\text{Potassium chlorate (heated) --> Potassium chloride + Oxygen}$ But I don't understand what the (heated) means in front of the first element. ...
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26 views

Analytically combining Dynamic Equilibria that have a two way affect?

Lets say I want to model a water system as the following set of equilibria: $\ce{H2O <=> OH- + H3O+}$ | $\ce{A=[OH^{-}][H3O+]}$ $\ce{CO2 + H2O <=> H2CO3}$ | ...
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1answer
260 views

Acid-base equilibrium of NH4CN

I'm having difficulties understanding this problem. We have in the problem that $K_a$ for $\ce{HCN} = 6.2\cdot10^{-10}$ and $K_b$ for $\ce{NH3} = 1.8\cdot10^{-5}$. Write chemical equations to ...
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3answers
102 views

Why is the equilbrium constant expressed the way it is?

Why are the two molarity's multiplied and not added and why is each raised to the power of the coefficient rather than multiplied by it? What is the reasoning behind this form? Was it simply ...
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2answers
27 views

Finding the value of stoichiometric coefficient x

$\ce{2A_{(s)} + xB_{(g)} <=> 3C_{(g)}}$ $K_p=19.3, K_c=0.45, T=523K$ I work $\Delta n$ to be 1, So would $x$ be 1 or 2? I'm not sure if the coefficient is part of $\Delta n$.
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1answer
77 views

Relationship between rate equation and equilibrium constant

I have read mannaia's answer on the question of 'rate order and confusion', as well as Nicolau Saker Neto's answer to a related question. They have both been very helpful. As I understand, the ...
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2answers
33 views

Find the color of the solution

The acid-base indicator methyl red has a $K_{a}$ = $1 \times 10^{-5}$. Its acidic form is red while its alkaline form is yellow. If methyl red is added in a colorless solution with a $pH = 7$, the ...