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What exactly is the requirement (in terms of saturation) for a reaction to be at equilibrium? |
If you add solid sodium chloride to a saturated sodium chloride solution, it is still at equilibrium. If you increase the sodium ion concentration of the chloride ion concentration (by e.g. adding a high concentration of NaOH or LiCl), then the solution is supersaturated and will not be at equilibrium.
> What exactl... |
To my understanding, M. Farooq correctly address the OP's problem. As noted in his answer:
>$\pu{mMol}$ is not an acceptable notation, it better be $\pu{mmol}$ to be read as millimole. This is not the same as $\pu{mM}$, which is read as millimolar. The former is an amount unit, the latter is a concentration unit.
... |
If you add solid sodium chloride to a saturated sodium chloride solution, it is still at equilibrium. If you increase the sodium ion concentration or the chloride ion concentration (by e.g. adding a high concentration of NaOH or LiCl), then the solution is supersaturated and will not be at equilibrium.
> What exactl... |
This is part of my homework. Given the chemical equation :
$$\ce{Sb2S3_{(s)} + 3H2_{(g)} <=>2Sb_{(s)} + 3H2S_{(g)}}\text{ }K_{p}=0,429\text{ at }713\text{K}$$
What is the value of $K_c$ for the reaction?
I used the formula : $K_p = K_c(RT)^{\Delta n}$, but I know that $\Delta n$ considers only the coeffici... |
How to find the value of $K_c$? |
I thought that the structure will be aromatic and stabilised because[![enter image description here][1]][1] one of the lone pairs being delocalised with the help of conjugated double bond system but still only 3 pi bonds will be present at a time and 2 lone pairs so the answer should be 6 but the book says the answer i... |
How many pi electrons are there in the molecule? |
How many π-electrons are there in 2-methylene-2H-pyran? |
When silver nitrate and hydrochloric acid are put together in a container, they form silver chloride. If you're given information about the reactants (including temperature change, heat capacity, and mass of reactant aqueous molecules), then you can find the kinetic energy change of the system.
What I want to know ... |
Is the Kinetic Energy Change of a system (q) equal to the Enthalpy Change of a system (delta_H)? |
How to name the following compound? |
What textbook states about the formation of electric double layer:
> When silver nitrate solution is added to potassium iodide solution the precipitated silver iodide adsorbs iodide ion from dispersion medium and negatively charged colloidal solution results. Having acquired a negative charge by selective adsorption o... |
What textbook states about the formation of electric double layer:
> When silver nitrate solution is added to potassium iodide solution the precipitated silver iodide adsorbs iodide ion from dispersion medium and negatively charged colloidal solution results. Having acquired a negative charge by selective adsorption o... |
When silver nitrate and hydrochloric acid are put together in a container, they form silver chloride. If you're given information about the reactants (including temperature change, heat capacity, and mass of reactant aqueous molecules), then you can find the kinetic energy change of the system.
What I want to know ... |
Is the Kinetic Energy Change of a system (q) equal to the Enthalpy Change of a system (∆H)? |
When silver nitrate and hydrochloric acid are put together in a container, they form silver chloride. If you're given information about the reactants (including temperature change, heat capacity, and mass of reactant aqueous molecules), then you can find the kinetic energy change of the system.
What I want to know ... |
Is the kinetic energy change of a system (q) equal to the enthalpy change of a system (∆H)? |
What textbook states about the formation of electric double layer:
> When silver nitrate solution is added to potassium iodide solution the precipitated silver iodide adsorbs iodide ion from dispersion medium and negatively charged colloidal solution results. Having acquired a negative charge by selective adsorption o... |
What textbook states about the formation of electric double layer:
> When silver nitrate solution is added to potassium iodide solution the precipitated silver iodide adsorbs iodide ion from dispersion medium and negatively charged colloidal solution results. Having acquired a negative charge by selective adsorption o... |
I am designing a machine that uses paper-thin sheets of silver. I am trying to find a material that can cover the silver to prevent it from tarnishing over time. The material does not have to be abrasive-resistant, as the silver will be placed in a controlled environment. Because of this, appearance does not matter. Pe... |
I am trying to design a machine that can convert carbon dioxide into methanol and/or hydrocarbons. My design requires PdZn-Ag foam (nanoparticles), which is made by depositing palladium-zinc vapor onto a silver base, but this seems to be very costly. So is there is a cheap and effective way of producing a measurable am... |
Is there a cheap and effective way to make PdZn-Ag foam? |
How do I find out if quinine or in generel if a compound is more more soluble in an acidic aqueous solution than an basic aqueous solution?
Here is the structural formula for quinine:
[![][1]][1]
[1]: https://i.stack.imgur.com/GUFI0.png |
Why is quinine more soluble in an acidic aqueous solution than an basic aqueous solution? |
How do I find out if Quinine or in general if a compound is more more soluble in an acidic aqueous solution than an basic aqueous solution?
Here is the structural formula for quinine:
[![][1]][1]
[1]: https://i.stack.imgur.com/GUFI0.png |
Why is Quinine more soluble in an acidic aqueous solution than an basic aqueous solution? |
To the best of my knowledge, the effective nuclear charge $Z_\mathrm{eff}$ is usually defined such that the potential energy of an electron in an atom, $\langle V \rangle$, can be expressed as
$$\langle V \rangle =
-Z_\mathrm{eff}\langle\psi|\frac{1}{|r - r_a|}|\psi\rangle$$
The Hartree-Fock expression for $... |
Out of the side chains of **aspartic acid**, **methionine**, **threonine**, and **tyrosine**, which is the least nucleophilic? |
how will the dielectric constant of water change when ethyl acetate is added?
The pKa value of weak acids in aprotic solvents will be lower than in protic solvents because the dielectric constant does not favor ionization. If I increase the % concentration of ethyl acetate in water and gradually increase it to nearly ... |
how will the dielectric constant of water change when ethyl acetate is added? |
How will the dielectric constant of water change when ethyl acetate is added?
The pKa value of weak acids in aprotic solvents will be lower than in protic solvents because the dielectric constant does not favor ionization. If I increase the % concentration of ethyl acetate in water and gradually increase it to nearl... |
How will the dielectric constant of water change when ethyl acetate is added? |
I often read that reactive organometallics must be handled under an inert atmosphere because they react with oxygen in the atmosphere. This applies to grignard reagents, organolithium reagents, and organozinc reagents.
What is the reaction of these organometallics with oxygen? I don't see how oxygen can be electroph... |
[![enter image description here][1]][1]
**Source:
Jonathan Clayden, Nick Greeves, Stuart Warren, Organic Chemistry 2th Edition, 339.**
The general idea I got so far, is that, carbocation will be more stable if the + charge at central C is dispersed.
How can a very electronegative atom bonded to C bearing le... |
>How will the dielectric constant of water change when ethyl acetate is added?
The $\mathrm{p}K_a$ value of weak acids in aprotic solvents will be lower than in protic solvents because the dielectric constant does not favor ionization. If I increase the $\mathrm{\text{%}}$ concentration of ethyl acetate in water and... |
Is sodium percarbonate the safest and by weight the most efficient oxygen generator? |
Aspartic acid < Tyrosine < Threonine < Methionine is the order of nucleophilicity of the amino acid side chains. So, Aspartic acid (neutral form) is the answer. Every side chain has a Oxygen or Sulphur (Methionine) group available for electron pair donation, but in Aspartic acid the Oxygen group has lesser inclination ... |
> For which pair of species is the difference in radii the
greatest?
>
>(A) $\ce{Li}$ and $\ce{F}$
>
>(B) $\ce{Li+}$ and $\ce{F^-}$
>
>(C) $\ce{Li+}$ and $\ce{O^2-}$
>
>(D) $\ce{O^2-}$ and $\ce{F^-}$
I am pretty sure it is not (D) as $\ce{O}$ and $\ce{F}$ are quite close to each other on the periodic... |
In the context of automobile repair work, assume a metal surface has rust on it. Does it matter if all of the rust is removed before the metal surface is painted? If it does matter, then why?
It appears that at least some will claim you can do this, e.g. the company [Krylon](http://www.krylon.com/how-to/faqs/product... |
> Changes in which factors affect both the rate and the rate
constant of a first order reaction?
>
I. temperature
>
>II. concentration
>(A) I only (B) II only
(C) Both I and II (D) Neither I nor II
I would think that the answer would be (C), both temperature and concentration.
Concentration would ... |
Just read https://chemistry.stackexchange.com/questions/35734/what-property-allows-ozone-to-absorb-uv-light together with excellent answers.
The driver here, i.e. the source of both the short and long wave UV, is of course sunlight. This is notably absent for six months of the year at the poles, so can anyone explain... |
Ozone Layer - why shouldn’t there be holes at the poles? |
> For which pair of species is the difference in radii the
greatest?
>
>(A) $\ce{Li}$ and $\ce{F}$
>
>(B) $\ce{Li+}$ and $\ce{F^-}$
>
>(C) $\ce{Li+}$ and $\ce{O^2-}$
>
>(D) $\ce{O^2-}$ and $\ce{F^-}$
I am pretty sure it is not (D) as $\ce{O}$ and $\ce{F}$ are quite close to each other on the periodic... |
>How will the dielectric constant of water change when ethyl acetate is added?
The $\mathrm{p}K_a$ value of weak acids in aprotic solvents will be lower than in protic solvents because the dielectric constant does not favor ionization. If I increase the $\mathrm{\text{%}}$ concentration of ethyl acetate in water and... |
Questions like these always appear simple, when in fact they are not. First of all it has to be clear that stability is no absolute concept. In this case one could ask which of the cations is most persistent, in other words is least reactive towards nucleophiles. With the exception of the tert-butyl cation, one could a... |
Importance of zinc blende and wurzite crystal structures for semiconductors? |
When I was a kid, I used to go to the pharmacy to buy sulfur and iron powder, then mix it together and heat it until it starts to react into iron sulfide. Put a chunk of iron sulfide into some vinegar, and you get a room smelling badly of rotten eggs. This experiment was also described in some "chemistry for kids" boxe... |
Producing hydrogen sulfide at home - how dangerous is it? |
What's the difference between the two molecules? I can always read about β-D-fructofuranose in the chemistry books, but unfortunately, I've never found any info concerning β-D-fructopyranose. Is there a big difference between them (apart from their ring structure)? |
Just read "https://chemistry.stackexchange.com/questions/35734/what-property-allows-ozone-to-absorb-uv-light" together with excellent answers.
The driver here, i.e. the source of both the short and long wave UV, is of course sunlight. This is notably absent for six months of the year at the poles, so can anyone explai... |
Ozone layer: why shouldn’t there be holes at the poles? |
My Space Exploration SE question [Are Mars' atmospheric CO₂, O₂ and CO in equilibrium? Are sunlight or chemical reactions involved?](https://space.stackexchange.com/q/41094/12102) begins:
>According to the NASA JPL video linked below the top five gases comprising the martian atmosphere include CO₂, O₂ and CO. Do the... |
would the same equilibrium concentration of carbon dioxide, carbon monoxide and oxygen always result for a given initial atomic carbon fraction? |
I found [here](https://en.m.wikipedia.org/wiki/Ionization_energies_of_the_elements_(data_page)) that the ionization energy of hydrogen is $1312 \;\text{kJ}/\text{mol}$ and for fluorine, it is $1681 \;\text{kJ}/\text{mol}$. Now clearly, from the data, we can see that hydrogen has a lower ionization enthalpy when compare... |
Why does hydrogen have a lower ionization energy than fluorine? |
**Chemistry SE Question:** Starting with a gas mixture of some combination of gases containing carbon and oxygen with a total carbon atomic fraction $f$, would it always reach the same equilibrium proportions of $\ce{CO2 + O2 + CO}$?
For example if I had an equal number of $\ce{CO2}$ and $\ce{O2}$ molecules then $f=... |
Would the same equilibrium concentration of carbon dioxide, carbon monoxide and oxygen always result for a given initial atomic carbon fraction? |
How many possible isomers (including optical/geometric ones) of C4H8O are there? |
I found [here](https://en.m.wikipedia.org/wiki/Ionization_energies_of_the_elements_(data_page)) that the ionization energy of hydrogen is $1312 \;\text{kJ}/\text{mol}$ and for fluorine, it is $1681 \;\text{kJ}/\text{mol}$. Now clearly, from the data, we can see that hydrogen has a lower ionization energy when compared ... |
I'm no expert but i think of it like this- there is a shortage of electrons, when the electrons try to satisfy two carbons in a double bond(in the empty p orbital), there is always a shortage somewhere else no matter what the electrons do, we can see this in the resonating structures, so finally they try to partially s... |
As we have seen that when we pour salt in water then it gets dissolved that means it is soluble in water.But when we pour sand into water then it doesn't dissolve in water that means it is insoluble but still sand gets wet.But there are certain substances which doesn't get wet by water for example sulphur particle does... |
> does the q value you find for the system equal to the ΔH value for the system?
It seems that the reaction is undergoing at constant pressure. In that case, q value is indeed equal to the ΔH value for the system.
> Worded differently, does the kinetic energy change of the system equal to the enthalpy change of t... |
I was wondering whether or not the reason some noble gases, like neon, fluoresce at particular frequencies of the visible spectrum is because of a Stokes effect? I mean, do the neon dimers get stretched out dramatically at a more LUMO state, resonating with high energy electricity due to the high stability of noble gas... |
Do Neon Lights Work Do To Stokes Shift? |
Wikipedia defines a cluster as an ensemble of bound atoms or molecules that is intermediate in size between a molecule and a bulk solid. What is meant by a bulk solid? I can't find a definition anywhere? Further, is this a good enough definition? |
> Given the two reduction half-reactions for the following fuel cell, determine the standard cell potential $E^\circ_\mathrm{cell}$,
$$\ce{CH4 (g) + 2 O2 (g) + 2 OH- (aq) -> CO3^2- (aq) + 3 H2O}.$$
Reduction half-reactions:
\begin{align}
\ce{CO3^2- (aq) + 7 H2O (l) + 8 e- &-> CH4 (g) + 10 OH- (aq)}&
E^\circ &= \pu... |
Why is francium not included in the reactivity series?
Why is potassium considered more reactive than francium?
I know that reactivity increases down the group, but why does it not apply here? |
> I know that reactivity increases down the group, but why does it not
> apply here?
Francium has a $\ce{[Rn] 7s^1}$ electron configuration. It is a relatively heavy element with atomic number $Z=87$. In such heavy elements, **relativistic effects become significant** and impact the reactivity and other physical ch... |
Recently my teacher asked us which of the following has the largest number of molecules? He gave us two options:
1. $\pu{36 g}$ of $\ce{H2O}$
2. $\pu{54 g}$ of $\ce{N2O5}$
I'm stuck, because both of them are having two moles of each of the respective molecules. And technically, the number of molecules equa... |
> I'm stuck, because both of them are having two moles of each of the respective molecules.
Are you sure?
\begin{align}
M(\ce{H2O}) &= \pu{18 g mol^-1} &
\implies \pu{36 g} &\mathop{\hat{=}} \pu{2 mol} \\
M(\ce{N2O5}) &= \pu{108 g mol^-1} &
\implies \pu{54 g} &\mathop{\hat{=}} \pu{0.5 mol} \\
\end{align} |
How do I balance the combustion reaction of butene? |
[![enter image description here][1]][1]
For compound D (shown in the figure attached above), how can I deduce its structure?
I undersand CO2 has been produced and thus the compound will no longer have the CO2H group attached, but what I do not understand is why the double bond will be affected and why an nitr... |
How could I deduce what this organic compound would be? |
Actually, here is a modification of your procedure involving some advanced radical chemistry with sulfur (see [Scheme 1 graphics and pages 6 to 7](https://pdfs.semanticscholar.org/533e/9a0b2e5d938abc555e267f2f9b1a6a29f720.pdf)) and the use of a photocatalyst with sunlight and oxygen from air.
My scheme is to burn a ... |
What's the difference between the two molecules? I can always read about β-D-fructofuranose in the chemistry books, but unfortunately, I've never found any info concerning β-D-fructopyranose. Is there a big difference between them (apart from their ring structure)?
And where can the furanose and the pyranose form be f... |
We have seen that, when we pour salt in water then it gets dissolved, that means it is soluble in water. But when we pour sand into water then it doesn't dissolve in water, that means it is insoluble, but still sand gets wet. But there are certain substances which doesn't get wet by water for example, sulfur particles ... |
I found [here](https://en.m.wikipedia.org/wiki/Ionization_energies_of_the_elements_(data_page)) that the ionization energy of hydrogen is $\pu{1312kJ/mol}$ and for fluorine, it is $\pu{1681kJ/mol}$. Now clearly, from the data, we can see that hydrogen has a lower ionization energy when compared to fluorine.
I did no... |
I bought an alcohol hydrometer (scale 0 to 40%) to measure the alcohol in my home made beer, at the end of fermentat.ion and prior to bottling. While it is accurate on pure water @ 0, home made wine @ 8% and gin at 40%. It will not do beer? Ive even tried it on canned beer of 5% and then it shows a negative figure of... |
**Chemistry SE Question:** Starting with a gas mixture of some combination of gases containing carbon and oxygen with a total carbon atomic fraction $f$, would it always reach the same equilibrium proportions of $\ce{CO2 + O2 + CO}$?
For example if I had an equal number of $\ce{CO2}$ and $\ce{O2}$ molecules then $f=... |
>[![enter image description here][1]][1]
For compound **D** (shown in the figure attached above), how can I deduce its structure?
I understand $\ce{CO2}$ has been produced and thus the compound will no longer have the $\ce{-COOH}$ group attached, but what I do not understand is why the double bond will get af... |
Ed has already explained the main ideas. Stokes shift is associated with the concept when you excite a substance with light (or electromagnetic radiation). In neon discharge tubes you are using electrical energy to excite the neon atoms. All the emission you see is from neon atoms. Also recall, that molecular emission ... |
Molecule with reversible exothermic confirmational change? |
Careful, as sodium percarbonate (basically $\ce{3Na2CO3.2H2O2}$) is usually marketed as a chlorine-free bleach. However, it has an additive, TAED, which acts as a key activator (see, for example, [Wikipedia on OxiClean](https://en.m.wikipedia.org/wiki/OxiClean), which is not even listed on the label, namely, TetraAcety... |
Careful, as sodium percarbonate (basically $\ce{3Na2CO3.2H2O2}$) is usually marketed as a chlorine-free bleach. The latter usually has an additive, TAED, which acts as a key activator (see, for example, [Wikipedia on OxiClean](https://en.m.wikipedia.org/wiki/OxiClean), which is not even listed on the label, namely, Tet... |
Careful, as sodium percarbonate (basically $\ce{3Na2CO3.2H2O2}$) is usually marketed as a chlorine-free bleach. The latter usually has an additive, TAED, which acts as a key activator. See, for example, [Wikipedia on OxiClean](https://en.m.wikipedia.org/wiki/OxiClean), where not even listed on the label is TetraAcetylE... |
During the weekend, I wanted to conduct a kid experiment - the copper dendrite formation. I was (partially) successful and now I would like to know „what went wrong” ;)
The procedure was taken from the weird science page (unfortunately in polish only): https://weirdscience.eu/Dendryty%20miedzi.%20Prawie%20jak%20%C5%... |
A kids experiment. Why dendrites formed during dilute CuSO4 electrolysis are black? |
When I was a kid, I used to go to the pharmacy to buy sulfur and iron powder, then mix it together and heat it until it starts to react into iron sulfide. Put a chunk of iron sulfide into some vinegar, and you get a room smelling badly of rotten eggs. This experiment was also described in some "chemistry for kids" boxe... |
An Oxidizing agent pulls the electron cloud of the substance being oxidized towards itself, for example:
$$\ce{F2 + 2 X- → 2F^- + X2}\qquad (\ce{X} = \ce{Cl}, \ce{Br}, \ce{I})$$
We also know that Fluorine has very high charge/mass ratio as it is very small in size,
its electron gain enthalpy is very high.
... |
The use of "bi" for 'two" denotes that there are *two different* cations (e.g. $\ce{Na+, H+}$ in the examples), but it is confusing, because it could imply that there are two of a *single* cation, so its use is deprecated. Similarly, in English, [biweekly][1] can mean either *twice a week* or *every two weeks*.
The... |
During the weekend, I wanted to conduct a kid's experiment - the copper dendrite formation. I was (partially) successful and now I would like to know "what went wrong” ;)
The procedure was taken from the [weird science page](https://weirdscience.eu/Dendryty%20miedzi.%20Prawie%20jak%20%C5%BCywe.html) (unfortunately i... |
A kids experiment: Why dendrites formed during dilute CuSO4 electrolysis are black? |
During the weekend, I wanted to conduct a kid's experiment - the copper dendrite formation. I was (partially) successful and now I would like to know what went wrong.
The procedure was taken from the [weird science page](https://weirdscience.eu/Dendryty%20miedzi.%20Prawie%20jak%20%C5%BCywe.html) (unfortunately in po... |
Why are dendrites formed during dilute CuSO4 electrolysis black? |
I have tried to detect tylosin tartrate from the mixture of doxycycline hyclate using $\pu{0.01 M}$ $\ce{HCl}$ as solvent, at $\pu{290 nm}$ the method fails only specificity was good.
Can you suggest any other method? |
An oxidizing agent pulls the electron cloud of the substance being oxidized towards itself, for example:
$$\ce{F2 + 2 X- -> 2F- + X2}\qquad (\ce{X} = \ce{Cl}, \ce{Br}, \ce{I})$$
We also know that fluorine has very high charge/mass ratio as it is very small in size, its electron gain enthalpy is very high.
**Al... |
An oxidizing agent pulls the electron cloud of the substance being oxidized towards itself, for example:
$$\ce{F2 + 2 X- -> 2F- + X2}\qquad (\ce{X} = \ce{Cl}, \ce{Br}, \ce{I})$$
We also know that fluorine has very high charge/mass ratio as it is very small in size, its electron gain enthalpy is very high.
**Al... |
I am trying to determine how much Sodium dichloro-s-triazinetrione dihydrate powder I should add to water to create a dilution that can be injected into my water supply to react with the Hydrogen Sulfide and remove it.
I have a system in my home that uses Sodium hypochlorite (Bleach) and water. There is a 30 gallon... |
How much of Sodium dichloro-s-triazinetrione dihydrate should i use? |
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