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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30 views

How to calculate the Gibbs energy for the vaporisation of solid ammonia?

Given that $P_{\ce{NH3}}=\mathrm{10~atm}$ at $298\ \mathrm K$, calculate the $\Delta G^\circ$ of the reaction $$\ce{NH3(s) <=> NH3(g)}$$ I'll begin solving the problem... I'm using the formula ...
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2answers
23 views

Henderson-Hasselbalch Question

I am struggling with what appears to be an extremely easy pH problem that uses the Henderson-Hasselbalch equation. The problem and answer provided by the book is given below. I understand where the ...
1
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0answers
18 views

Precipitation of multiple ions in solution

I'm trying to figure out what exactly happens if you have 2 salts dissolved and then slowly evaporate the water: I have a solution containing 1 mol each of $\ce{Na+}$, $\ce{K+}$, $\ce{Cl-}$ and ...
-1
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0answers
15 views

What is the equilibrium equation for this reaction? [on hold]

For a Chemistry assignment I was asked to find the equilibrium equation for the following: When Potassium Thiocyanate ($\ce{KSCN}$) is mixed with Iron (III) Nitrate ($\ce{Fe(NO3)3}$ in solution, ...
0
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0answers
13 views

Addition of inert gas to equilibrium mixture under constant pressure [duplicate]

Adding inert gas under constant volume will not disturb equilibrium. But I want to know what would happen if inert gases are added at constant pressure. If total pressure remains constant and inert ...
6
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0answers
42 views

Which graph shows Chemical Equilibrium?

So my teacher started the explanation of Chemical Equilibrium saying.. The concentration does not change with time. And, gave us certain graphs asking which ones show chemical equilibrium. I cannot ...
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21 views

Chemical Equillibria Comparisons

In which of the following reactions is the equilibrium farthest to the left? a) $\ce{P4O10 + $x$ H2O <=> 4 H3PO4(aq)}$ b) $\ce{AlCl3 + $x$ H2O <=> [Al(H2O)6]^3+ + 3 Cl- (aq)}$ c) ...
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1answer
13 views

Get K for a weak acid equilibrium when given the ionization percentage

There is some weak acid with a concentration of $0.0284$ M, which is ionized by $6.70$%. What is the value of $K_a$? So we got $$\ce{HA <=> H+ + A-}$$ The formula for the ionization ...
3
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1answer
19 views

Find the stoichiometric coefficient of a reactant given Kp, Kc, and the stoichiometric coefficient of the product

Have an hypothetical equilibrium reaction: $$\ce{2A(s) + $X$B(g) <=> 3C(g)}$$ With the constants $$K_p = 0.0105\\K_c=0.45$$ Both at $250\ \mathrm{^\circ C}$. What is the ...
3
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1answer
15 views

Calculating [HI] given Kc, [H2], and [I2] for the reaction 2HI <-> H2+I2

In the reaction in equilibrium $$\ce{2HI} \leftrightarrow \ce{H2 + I2}$$ The value $K_c$ is $0.0198$ at $721$ K. Calculate $\ce{[HI]}$ at $721$ K if $\ce{H2} = 0.0120$ M and $\ce{I2} = ...
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0answers
23 views

If you remove product from an equilibrated system, won't the system be equilibrated anyway?

Have a system in equilibrium. The reagents cause the substance to be color blue. The products make it green. On equilibrium, the substance is yellow. What happens when you remove product? ...
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2answers
40 views

Can acid concentration be determined from Ka values in a titration? [duplicate]

Say I have a sample of vinegar and I want to find the concentration of ethanoic acid in it. So I perform a titration using a $\mathrm{pH}$ meter, and using that data I can draw a $\mathrm{pH}$ curve ...
4
votes
2answers
44 views

Why does equilibrium exist?

I've read an article that equilibrium exists when $G$ (Gibb's free energy) becomes minimum. If formation of products decreases Gibb's free energy, why won't the reaction proceed to completion so that ...
0
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1answer
26 views

Why are the reactants in the solubility product constant multiplied by their coefficients and raised to the power of their coefficients?

It is probably easiest for me to explain the question in an example. Consider the following chemical reaction: $\ce{MgF2(s) -> Mg^{2+} (aq) + 2F- (aq)}$ Plugging this into the formula for the ...
3
votes
2answers
55 views

Le Chatelier's Principle and Rate constants

I am confused about the application of Le Chatelier's principle to reaction systems. Consider the reaction: $$\ce{H2O2(g) <=> 2OH{.}(g)}\quad\text{(i)}$$ to be at at equilibrium. As the pressure ...
3
votes
1answer
61 views

Le Chatelier's Principle: What does temperature do gas concentrations?

I am confused about a specific part of Le Chatelier's Principle. My question revolves around a homework assignment question: $$\ce{2SO2(g) + O2(g) <=> 2SO3(g)} \qquad\Delta H^\circ = ...
2
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0answers
62 views

kinetic reaction rate greater than extent of reaction for equilibrium

I'm comparing a model with chemistry at equilibrium versus a kinetic one. I take a network of two reactions: methane steam reforming (MSR) and water gas shift (WGS) at 700°C. I calculated extent of ...
0
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1answer
28 views

How does Le Chatelier's principle work in a gaseous system?

My textbook said Le Chatelier's principle applies normally to gases but there is no explanation. I did some googling and it said if you increase the pressure, it will shift to the side with less moles ...
0
votes
1answer
23 views

percent ionization explanation [duplicate]

Using a weak acid as an example: $$\ce{HOAc <=> AcO- + H+}$$ The position of this equilibrium shifts to the right with increasing dilution. I have found textbooks that say this, but do not ...
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0answers
16 views

The reason for bicarbonate acting as a buffer

My question is: what is the primary reason that bicarbonate ($\ce{HCO3^-}$) can act as a buffer in a solution? The two (possibly) relevant equations that I can think of are $$ \ce {H2CO3 + H2O ...
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0answers
25 views

Belousov–Zhabotinsky Reaction

An experiment in my lab was about the Belousov–Zhabotinsky reaction and we measured 2 times - the induction period, which was the amount of time it took for the solution to change color and back for ...
0
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0answers
21 views

Using equilibrium constant in gibbs equation [duplicate]

In my chemistry textbook, it is written that : Gibbs energy for a reaction in which all reactants and products are in standard state, $\Delta_\mathrm{r}G^\circ$ is related to the equilibrium ...
0
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1answer
27 views

Finding the equilibrium constant

I have tried to solve it algebraically, using the data I'm provided with, but still, I'm not capable of proving that in this particular case, the equilibrium constant is independent from the volume, ...
2
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2answers
94 views

Equilibrium of more than two inter reacting species

We know that equilibrium in a chemical system is attained when forward and backward reaction rates are equal. What if the reaction mixtures involve more than one reaction? For example, consider three ...
2
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1answer
94 views

How would you describe this?

This equation has been described as an equilibrium in an article, how would you explain it to someone with not a lot of understanding of it. The equation is: $\ce{CH3COOH <-> CH3COO- + H+}$ ...
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1answer
22 views

calculate the pressure at equilibrium

Given that $K=18$ for the equilibrium below, calculate the total pressure in a sealed vessel initially containing only $\ce{NH4I(s)}$, that reaches equilibrium. $$\ce{NH4I(s) ...
5
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0answers
52 views

A doubt on phase equilibrium?

Below is a transcript of this doubtful question: A weak monobasic organic acid HA issoluble in both solvents, water and $\ce{CHCl3}$. 500.0 cm$^{3}$ of a solution of $\ce{HA}$ is 0.057 mol ...
2
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2answers
107 views

About pH of an aqueous solution of SO2

How can I compare pH of an aqueous solution of $\ce{SO2}$ with that of pure water qualitatively? And I want to know what happen to the pH of an aqueous solution of $\ce{SO2}$ if I aerate it by ...
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1answer
56 views

A doubt on equilibrium question?

To be honest this is a homework question. Below you can see a screenshot of it . Below you can see what I have tried , This is what I have got as the answer for Roman number one \begin{align}K_a ...
1
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1answer
36 views

When is equilibrium analysis appropriate?

What is a good rule of thumb to use to determine if equilibrium is the appropriate assumption? I assume it is mainly to do with the time scales of the problem, meaning if the reaction time scales are ...
5
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2answers
144 views

How will the equilibrium partial pressure of carbon dioxide be affected?

\begin{equation}\ce{CaCO3(s) -> CaO(s) + CO2(g)}\quad\Delta H^\circ = +556\ \mathrm{kJ/mol} \tag{endothermic}\end{equation} How will the equilibrium partial pressure of $\ce{CO2}$ be affected if ...
3
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1answer
55 views

Equilibrium constant in terms of mole fractions

$$\ce{CO + H2O <=> CO2 + H2}$$ A stoichiometric mixture of $\ce{CO(g)}$ and $\ce{H2O(g)}$ is allowed to reach equilibrium. $x$ is the mole fraction of $\ce{H2(g)}$ present. I am meant to ...
3
votes
1answer
64 views

Temperature dependence of equilibrium constant

On looking over the usefulness of quantity enthalpy change, I found that it can also be used to calculate temperature dependence of equilibrium constant, and I was wondering how could it be done, it ...
-1
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1answer
61 views

Final concentration … How to calculate it? [closed]

My question is here but i just want to find out how to go about it? If 50.0 mg of $\ce{CO3^2-}$ and 50.0 mg of $\ce{Ca^{2+}}$ are present in 1 liter of water, what will be the final ...
2
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2answers
47 views

What is the difference between these equations for the Contact process?

Some webpages describe the contact process as this (I left out $\ce{SO2}$, $\ce{SO3}$ production): $\ce{SO3 + H2SO4 -> H2S2O7}$ After this, it is controllable to add water to the oleum therefore ...
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0answers
28 views

How the heat a large amount of water that is safe to use?

I would like to know how heat up a large amount of water ( assumption : 100 liter ) that people could use to take their bath and also it would not be dangerous even if they accidentally ingested it ? ...
5
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1answer
843 views

How to find pH by mixing two solutions of different concentrations?

A mixture is made by combining 110 mL of 0.15 M $\ce{HCl}$ and 215 mL of 0.055 M $\ce{HI}$. What is the pH of the solution? $$\ce{HCl -> H+ + Cl-}$$ $$\ce{HI -> H+ + I-}$$ According to ...
4
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3answers
257 views

Which of the following compounds would result in the reaction being more active in the reverse direction?

$\ce{Fe(OH)2 (s) <=> Fe^{2+} + 2OH-}$ The reaction will be more active in the reverse direction if .......... is added a) $\ce{KOH}$ b) $\ce{Na2S}$ c) $\ce{Fe(OH)2}$ ...
2
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1answer
68 views

Chemical equilibrium and Le Chatelier's principle

Choose: $$\ce{Energy + 2KClO3 (s) <=> 2KCl(s) + 3O2 (g)}$$ The reaction will be more active in the reverse direction if: 1) $\ce{O_2}$ is added 2) more $\ce{KCl}$ salt is added. 3) More ...
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1answer
76 views

How to calculate the mass of phosgene in the equilibrium mixture of carbon dioxide and dichloride? [closed]

I'm stuck on the last question of my homework and I really need some help! How much $\ce{COCl2}$ grams is in the equilibrium mixture? Consider the reaction: $$\ce{CO(g) + Cl2(g) <=> ...
2
votes
1answer
54 views

Approximating the concentration of ions when a salt dissociates

In my textbook written that: Given that $K_\mathrm{sp}(\ce{Ag2CrO4})=9.0\times 10^{-12}$, consider the solubility of $\ce{Ag2CrO4}$ in a $0.100\:\mathrm{M}$ solution of $\ce{AgNO3}$. Initial ...
2
votes
1answer
78 views

Is solubility in Qsp affected by coefficient?

Related to my previous question: Is solubility coefficient affected if ion data is given in Ksp? $200\,\mathrm{mL}$ solution of $0.02\,\mathrm{M}\,\ce{AgNO3}$ is added to $200\,\mathrm{mL}$ ...
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50 views

Keto Enol Equilibrium for Claisen Condensation Products

Do Claisen Condensation products prefer the di-keto form, or a keto/enol form due to increased conjugation and hydrogen bonding?
2
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1answer
51 views

Why does raising the temperature affect the mass of dissolved solute? [closed]

Consider a solution of $\ce{KOH}$ which is in equilibrium with undissolved $\ce{KOH}$ at $25\ \mathrm{^\circ C}$. After raising the temperature to $50\ \mathrm{^\circ C}$, the mass of undissolved ...
10
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2answers
214 views

How to calculate the pH of a saturated solution from its solubility constant Ksp and acidity constant Ka?

Given that $K_{\mathrm{sp}}(\ce{CaF2})=3.2\cdot 10^{-11}$, $K_{\mathrm{a}}(\ce{HF})=10^{-5}$, and $K_{\mathrm{w}}=10^{-14}$. Calculate $\mathrm{pH}$ of saturated $\ce{CaF2}$. Edit: Since my ...
3
votes
1answer
41 views

Is solubility coefficient affected if ion data is given in Ksp?

Recently I've been looking at this website, which says: The $K_{\mathrm{sp}}$ of $\ce{Cr(OH)3}$ is $6.70 \times 10^{-31}$ Problem 1: What is the minimum $\mathrm{pH}$ at which $\ce{Cr(OH)3}$ ...
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1answer
56 views

Need help with some equilibrium questions [closed]

I don't understand why the answer to this questions is A. I thought that the answer should be B since reaction 2 is just the reverse of reaction 1, and as such the position of products and reactants ...
2
votes
1answer
76 views

What is the effect of the temperature on the no of moles in an equilibrium system?

Here's something that makes me confuse. What will happen to the total no of moles in a system if the temp is raised. Will it increase? If so how is that possible.? Say we have an equlibrium, $$\ce{2P ...
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1answer
44 views

What is the value for the reverse reaction?

My question deals with the reaction $\ce{2NO(g) + O2(g) -> 2NO2(g)}$ with $K_c = 1752$. This is what I have so far; $K_c$= products over reactants, so is the reverse reaction reactants over ...
1
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1answer
41 views

Do all the precipitates undergo an equilibrium with its respective ions, why can't they dissociate fully?

I’m really confused about this. If we consider $\ce{Ca3(PO4)2}$, it can be seen it undergoes an equilibrium. But why it’s an equilibrium? This is the equilibrium it undergoes ...