The state in which both reactants and products are present at concentrations which have no further tendency to change with time.
0
votes
0answers
27 views
I need the mathematical equations that represent the absorption of CO2 in a column
I want to mathematically model a carbon dioxide absorption column using the equilibrium model (not rate based or dynamic) but I am having trouble finding the same number of numerical equations as I ...
1
vote
2answers
38 views
What does it mean for a reaction to favor the reactants/products?
(This example is purely hypothetical.)
You have the reaction $$\ce{H2(g) + O2(g) <-> H2O2(g)} \text{(500K)}$$
The reaction reaches equilibrium at the following concentrations:
$$\ce{[H2]} = ...
1
vote
1answer
48 views
Why x in equilibrium calculations can be “ignored”
You don't need to work out anything for me. I am just giving an example so you can explain something to me.
For example:
$$\ce{ClF3(g) <=> ClF(g) + F2(g)}\\ \ \ K_c=8.77\times10^{-14} \ \ @\ ...
2
votes
3answers
74 views
Le Chatelier's Principle: How can the equilibrium shift, while Kc remains constant?
The answer is D.
I understand that when more H+ ions are added, the reaction shifts in reverse.
So I've understood that this is known as having the equilibrium shift to the left, toward the ...
1
vote
2answers
70 views
The reasoning behind predominance diagrams
Consider a one dimensional predominance diagram for a simple acid-base reaction:
$$\ce{AH <=> A^- + H^+}$$
With equilibrium constant:
$$K_a = \frac{[A^-]_{eq}[H^+]_{eq}}{[AH]_{eq}}$$
If I ...
2
votes
1answer
55 views
$K_c$ expression for heterogeneous equilibrium
Consider this reaction. :-
$CaCO_3(s) \rightleftharpoons CaO(s) + CO_2(g)$
for this, Kc=[ $CO_2$ g)]
For a given temperature, Kc will remain fixed. That means, the amount of $CO_2$ released ...
2
votes
2answers
55 views
Equilibrium constant
I know that equilibrium constant depends on temperature and pressure. But according to Le Chatelier's principle when we change pressure of reagents the equilibrium is the same. Why?
1
vote
2answers
71 views
how many anions, acid molecules, hydronium cations, and water molecules in a certain volume of aqueous solution of an acid
The acid in question has pKa about 1.29. Density of 98% w/w solution is $d=1.323 \,\rm{g/cm}^3$. I would like to find the number of undissociated acid molecules ($\ce{HX}$), water molecules ...
0
votes
0answers
42 views
Salt Hydrolysis
Referring to this, when "hydrolysis of a salt" is its reaction with water:
How is it that both the cation and anion of the salt are reacting in an equal amount with water?
To state this specifically ...
0
votes
1answer
31 views
Ksp of Manganese Phosphate
I can't find the $K_{sp}$ value for Manganese Phosphate ($Mn_3(PO_4)_2$) anywhere online. Has it been measured? What is it?
0
votes
1answer
73 views
Spontaneous inequilibrium in a gas in an isolated system?
Can an isolated system(of several phases) in equilibrium by itself move out of equilibrium?
if a system contains for example an inflammable gas dispersed with another combustible gas such that the ...
1
vote
1answer
46 views
At equilibrium, the mass of reactants and products are equal. Does that mean the reaction stops?
This one is troubling me, and I even got it wrong in my exam:
at equilibrium the mass of reactants and products are equal, does that mean the reaction stops?
...
0
votes
1answer
70 views
How do you find the pH of a solution with a known pKa and Molarity?
How do you find the pH of a solution with a known pKa and Molarity?
3
votes
1answer
48 views
$K_{eq} $ vs $K_c$
I was wondering if there was a difference between $K_{eq}$ and $K_c$. I think they both refer to the Equilibrium Constant. If I'm wrong, could you please tell me the difference between the two? ...
3
votes
2answers
64 views
Interpreting equilibrium equations correctly
I've watched over this Khan video titled "Reactions in Equilibrium" and am still confused on the interpretation of equilibrium. Reactions in Equilirbium
$\ce{N2(g) + 3H2(g) <=>2NH3(g)}$
...
3
votes
1answer
68 views
Influence of solubility at different pHs on the complexation constants
Given some small chemical compounds whose solubility varies with pH, and in the case of compounds that can form complexes, I have seen that the complexation constant varies with pH. I think there ...
1
vote
0answers
45 views
Selectivity Coefficients of Ion Exchange Resins - Selectivity Reversal with TDS / Ionic Strength
I'm currently studying ion exchange resins and generally getting a bit stuck on some points of information which I do not fully understand / are not very well explained within the literature.
I ...
4
votes
1answer
45 views
Chemical Equilibrium - Why do changes in pressure cause a shift in the ratio of products and reactants?
I understand Le Chatelier's principle and how every change to an equilibrium system causes an opposing reaction from the system. I also understand how, when pressure is increased, the equilibrium ...
3
votes
1answer
132 views
Simultaneous equilibria
Rephrasing:
The following reactions are a small example of my big system
$$(1)\ \ce{A + B <=> AB}$$
$$(2)\ \ce{AB -> CB}$$
$$(3)\ \ce{A -> C}$$
$$(4)\ \ce{C + B <=> CB}$$
with
...
1
vote
1answer
83 views
How do I calculate partial pressure here?
I need some help with partial pressures of reactions for a fuel cell project. The overall reaction for a fuel cell is
$$\ce{H_{2} +\frac{1}{2}O_{2}->H_{2}O}$$
Which means that the mole fraction ...
0
votes
0answers
40 views
Determine Keq for a solution that has equal activities for H₂S and SO₄-? [closed]
I know that I need to first calculate the redox half reactions for the reduction of sulfate to find log k... but I'm stuck even there! Help please!
6
votes
1answer
71 views
Are redox half-reactions “real”?
Are the half-reactions used in analyzing redox reactions a real thing or are they a conceptual shortcut?
Is there a way to, however briefly, run a half-reaction by itself without the corresponding ...
0
votes
0answers
36 views
How much of the anion species is left over after the first precipitation?
I've figured out the first part of this problem, that barium phosphate is the first to precipitate (due to lower $K_{sp}$) but I can't seem to figure out the other part. I even read about selective ...
4
votes
4answers
234 views
Why are equilibrium constants unitless?
I haven't quite reached the point where I can read a full-fledged text on chemical kinetics and thermodynamics yet, so bear with me, please.
I'm wondering why a value like $K_{eq} = ...
6
votes
1answer
276 views
How to calculate the equilibration time of two connected chambers of salt solution, initially at different concentrations?
I am trying to build a system of two connected chambers, one of which is also connected to a cuvette, so I can perform a spectrometry experiment with different concentrations of KNO3 solution. In its ...
1
vote
2answers
2k views
Degree of dissociation in equilibrium problem
In my textbook, for calculating the percentage dissociation of $HF$ for the given equation:
$$\ce{HF + H2O <-> H3O+ + F-}$$
The solution is:
Initial Concentrations
$$[\ce{HF}] = 0.08M, \: ...
0
votes
2answers
483 views
Problems in the concept of ionic equilibrium
While trying to understand the solution of a problem given in my text book, I realized I'm having some difficulty with the solution. The problem is as folows:
The ionization constant of HF is $3.2 ...
5
votes
3answers
711 views
Reaction between Silver Nitrate and Aluminium Chloride
I googled a bit about what $\ce{AgNO3 + AlCl3}$ will become and found out the following:
$\ce{3AgNO3 + AlCl3 -> Al(NO3)3 + 3AgCl}$
But why? I know that $\ce{Ag}$ is higher up in the Reactivity ...
3
votes
1answer
105 views
Why is it that the bigger the side-chain is, its hydrogen atoms tend to be more equatorial?
The most stable cyclohexane form is the chair conformation but on the other hand, the bigger the side-chain of the cyclohexane is, its hydrogen atoms become more equatorial rather than axial, which ...
8
votes
3answers
263 views
What software can calculate aqueous solution equilibria?
What software is available out there to calculate the equilibrium in a set of reactions in aqueous solution? In particular, I'm interested in software general enough to simulate things like titration ...
8
votes
2answers
255 views
Gibbs free energy-minimum or zero?
A reaction proceeds towards the direction of lesser Gibbs Free energy (at constant T and P). So, we could say that Gibbs free energy at equilibrium is minimum.
On the other hand, we have $$\Delta ...
