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Raoult’s Law become a special case of [Henry’s Law][1] when $K_H^{Px} = P^\circ$, but where do these laws differ from each other?
There’s a statement in my text book which I’m having trouble understanding.
The statement:
> As a real solution approaches the limit of infinite dilution its components behave more ... |
Raoult’s Law ($p_A = \chi_A \cdot p_A^\circ$) becomes a special case of [Henry’s Law][1] ($p_A = K_H^{px} \cdot \chi_A $) when $K_H^{px} = p^\circ_A$, but where do these laws differ from each other?
There’s a statement in my text book which I’m having trouble understanding.
The statement:
> As a real solution ... |
For a fixed amount of a real gas when a graph of Z vs P was plotted then at a very high pressure slope was observed to be 0.01atm^(-1). At the same temperature and pressure if a graph is plotted between PV vs P then for 2 moles of the gas the y intercept is found to be 40 atm-litre. Calculate excluded volume in litres ... |
> For a fixed amount of a real gas when a graph of $Z$ vs $P$ was plotted, then at a very high pressure slope was observed to be $\pu{0.01 atm^-1}.$ At the same temperature and pressure if a graph is plotted between $PV$ vs $P,$ then for $\pu{2 mol}$ of the gas the $y$ intercept is found to be $\pu{40 atm L}.$ Calculat... |
> For a fixed amount of a real gas when a graph of $Z$ vs $P$ was plotted, then at a very high pressure slope was observed to be $\pu{0.01 atm^-1}.$ At the same temperature and pressure if a graph is plotted between $PV$ vs $P,$ then for $\pu{2 mol}$ of the gas the $y$ intercept is found to be $\pu{40 atm L}.$ Calculat... |
What is the stability order of the carbocation and carboanion? |
**TL; DR**: Yes, *perborate* and *peroxoborate* are both the same thing. *Perborate* is just more popular, but *peroxoborate* is a more literate name for the $\ce{[B2(O2)2(OH)4]^2-}$ ion.
----------
A *perborate* is a name attributed historically in XIX century to the compounds containing $\ce{BO3-}$ anion (see e... |
The simple rules don't work with complicated examples. There are non-chiral molecules with "stereocenters", and chiral molecules lacking "stereocenters". The textbook example for your question is 1,4 dichloro cyclohexane:
[![https://chem.libretexts.org/@api/deki/files/8171/14diclc6.gif?revision=1][1]][1]
[1]... |
The simple rules don't work with complicated examples. There are non-chiral molecules with "stereocenters", and chiral molecules lacking "stereocenters". The textbook example for your question is 1,4 dichloro cyclohexane:
[![https://chem.libretexts.org/@api/deki/files/8171/14diclc6.gif?revision=1][1]][1]
>The wa... |
The simple rules don't work with complicated examples. There are non-chiral molecules with "stereocenters", and chiral molecules lacking "stereocenters". The textbook example for your question is 1,4 dichloro cyclohexane (or 1-chloro 4-bromo cyclohexane to get even closer to your example):
[, and [Poynting's correction](https://en.wikipedia.org/wiki/Poynting_effect) is negligible. Then Raoult's la... |
So I've come across this lovely spectrum of a compund where only its chemical formula is given with C5H9NO.
I have made the pictures of the spectrum available below.
obviously there is some pretty hefty coupling going on but I cant really figure out what it could be.
So far I think we definitely have a CH3 group tha... |
Consider a closed binary mixture with constant volume $V$ held at constant temperature $T$. Assume the vapor is an ideal gas mixture, the liquid is an [ideal mixture](https://en.wikipedia.org/wiki/Ideal_solution), and [Poynting's correction](https://en.wikipedia.org/wiki/Poynting_effect) is negligible. Then Raoult's la... |
Consider a closed binary mixture with constant volume $V$ held at constant temperature $T$. Assume the vapor is an ideal gas mixture, the liquid is an [ideal mixture](https://en.wikipedia.org/wiki/Ideal_solution), and [Poynting's correction](https://en.wikipedia.org/wiki/Poynting_effect) is negligible. Then Raoult's la... |
So I've come across this lovely spectrum of a compund where only its chemical formula is given with C5H9NO.
I have made the pictures of the spectrum available below.
obviously there is some pretty hefty coupling going on but I cant really figure out what it could be.
So far I think we definitely have a CH3 group tha... |
As I understand it, if I mix $\ce{[Ag(NH3)2]NO3}$ and $\ce{Na2EDTA}$ the silver will complex much more strongly with the EDTA than the ammonia, and the hydrogen ions will protonate the ammonia, leaving $\ce{AgEDTA^{3-} + 2NH4+ +NO3- + 2Na+}$, preventing the formation of silver nitride. Does that make sense? I'm concern... |
Will disodium EDTA effectively destroy Tollens' reagent? |
What is the osmolarity of a solution that contains 4.00% (m/v) NaCl (fm = 58.44 g/mole) and 3.00% (m/v) glucose (fm = 180.18 g/mole)?
so I know you have to move your percents to mass soultion/Liter solution and multiply by number of moles in NaCL , which is 2 moles
2 osmol NaCl/ 1 mole Nacl
but I'm being thro... |
So I came across a problem in my chemistry textbook that brought up another question. The problem had to do with calculating the mass% composition of chlorine in a certain molecule. So to go about solving this, you could calculate the mass in grams of 1 mole of the molecule and divide the mass in grams of the correspon... |
Why do significant figure rules contradict each other? |
How do precipitation reactions behave in the absence of gravity, say on the International Space Station (ISS)? I have seen water taking the shape of a sphere and not that of the container in space due to its surface tension. It takes a spherical shape in order to minimize the energy due to forces of surface tension. In... |
How do Precipitation Reactions behave in the Absence of Gravity? |
The equilibrium constant at 227 ∘C for the equation
PCl5(g)↽−−⇀PCl3(g)+Cl2(g)
is p=4.50×103 bar . Calculate the value of Δ∘rxn at 227 ∘C .
I calculated this to be -34.97 kJ/mol. Wouldn't it just be -(.0083145kJ*mol^-1*K^-1)(500K)(ln(4.5*10^3))?
The second part of the question asks With the temperat... |
The equilibrium constant at 227 ∘C for the equation
PCl5(g)↽−−⇀PCl3(g)+Cl2(g)
is p=4.50×103 bar . Calculate the value of Δ∘rxn at 227 ∘C .
I calculated this to be -34.97 kJ/mol. Wouldn't it just be -(.0083145kJ*mol^-1*K^-1)(500K)(ln(4.5*10^3))?
The second part of the question asks With the temperat... |
> What is the osmolarity of a solution that contains $4.00\%$ (m/v) $\ce{NaCl}$ $(M = \pu{58.44 g mol-1})$ and $3.00\%$ (m/v) glucose $(M = \pu{180.18 g mol-1})?$
I know you have to convert percentages to mass soultion/Liter solution and multiply by number of moles in $\ce{NaCl},$ which is 2 moles:
$\pu{2 osmol}$... |
How to find osmolarity of a solution contatining salt and glucose? |
> The equilibrium constant at $\pu{227 °C}$ for the equation
> $$\ce{PCl5(g) <=> PCl3(g) + Cl2(g)}$$
> is $K_p = \pu{4.50E3 bar}.$ Calculate the value of $Δ_\mathrm{rxn}G^\circ$ at $\pu{227 °C}$.
> With the temperature at $\pu{227 °C}$ and the partial pressures of the gases of $p(\ce{PCl3}) = \pu{0.286 bar}... |
So I came across a problem in my chemistry textbook that brought up another question. The problem had to do with calculating the mass% composition of chlorine in a certain molecule.
So to go about solving this, you could calculate the mass in grams of 1 mole of the molecule and divide the mass in grams of the correspo... |
Finding a structure with the correct formula that matches the chemical shifts reasonably well is not so difficult.
The multiplet integrals, normalized such that the area corresponding to one H is $\approx 33$ suggests the following number of H (moving upfield): 1,1,2,2,3.
The upfield singlet suggests an uncouple... |
[This comment](https://space.stackexchange.com/questions/39456/rocket-explosion-compared-to-kt-of-tnt-has-one-ever-knocked-something-over-at-a?noredirect=1#comment127560_39456) below the question [Rocket explosion compared to kT of TNT; has one ever knocked something over at a distance?](https://space.stackexchange.com... |
Does the explosion of TNT include oxidation? |
[This comment](https://space.stackexchange.com/questions/39456/rocket-explosion-compared-to-kt-of-tnt-has-one-ever-knocked-something-over-at-a?noredirect=1#comment127560_39456) below the question [Rocket explosion compared to kT of TNT; has one ever knocked something over at a distance?](https://space.stackexchange.com... |
I am having a lot of trouble understanding the influence of volume on relative permittivity/static dielectric constant. I'm not really a chemist, but am using molecular dynamics to calculate relative permittivity for use in other work. This may be a silly question, but I would be very grateful for any pointers!
... |
Molecular dynamics: do I understand correctly that simulation volume influences relative permittivity calculations? If so, how is the result useful? |
I am having a lot of trouble understanding the influence of volume on relative permittivity/static dielectric constant. I'm not a chemist but am using molecular dynamics to calculate relative permittivity for use in other work.
A predecessor used this equation:
relative permittivity = 1 + [4 pi/ (3 kB T V)... |
I am having a lot of trouble understanding the influence of volume on relative permittivity/static dielectric constant. I'm not a chemist, but am using molecular dynamics to calculate relative permittivity for use in other work.
A predecessor used this equation:
relative permittivity = 1 + [4 pi/ (3 kB T V... |
AgNO3+NH4OH=AgOH+NH4NO3
AgOH is used for the reaction with aldehyde. But why can't we use silver hydroxide directly? |
Why don't we use silver hydroxide instead of Tollen's reagent for test of aldehydes? |
Imagine that you are focusing the raman laser right at the center of the vial sample.
For raman 180 degree backscattering sample geometry, can the inelastic scattering photons upon travel to the spectrometer becomes elastically scattered on way to it by the thick sample such that it is scattered outside the area?
... |
Consider a closed binary mixture with constant volume $V$ held at constant temperature $T$. Assume the vapor is an ideal gas mixture, the liquid is an [ideal mixture](https://en.wikipedia.org/wiki/Ideal_solution), and [Poynting's correction](https://en.wikipedia.org/wiki/Poynting_effect) is negligible. Then Raoult's la... |
I am having a lot of trouble understanding the influence of volume on relative permittivity/static dielectric constant. I'm not a chemist, but am using molecular dynamics to calculate relative permittivity for use in other work.
A predecessor used this equation for relative permittivity $ε_\mathrm{r}$:
$$ε_\ma... |
Do I understand correctly that simulation volume influences relative permittivity calculations? If so, how is the result useful? |
Imagine that you are focusing the raman laser right at the center of the vial sample with water (or any liquid) using 532nm laser.
[![enter image description here][1]][1]
[![enter image description here][2]][2]
(from "Photometric Standards for Raman Spectroscopy)
For raman 180 degree backscattering sample geom... |
Which is faster- SN1 or SN2? |
My book says, and I understand, that the $\mathrm{S_N1}$ mechanism is much faster for tertiary alkyl halides than primary. And the opposite for $\mathrm{S_N2}.$ This all makes sense. What I don't get is the conclusion it comes to next: hence, we predict that the primary alkyl halides will react primarily via $\mathrm{S... |
> 23. A given mass of gas expands from state **A** to state **B** by three paths 1, 2, 3 as shown in the figure below.
> [![PV diagram][1]][1]
> If $W_1,$ $W_2$ and $W_3$ are respectively, be the work done by the gas along three paths, then
> (A) $W_1 > W_2 > W_3$
> (B) $W_1 < W_2 < W_3$
> (C) $W_1 = W_2... |
Finding a structure with the correct formula that matches the chemical shifts reasonably well is not so difficult.
The multiplet integrals, normalized such that the area corresponding to one $\ce{H}$ is $\approx 33$ suggests the following number of $\ce{H}$ (moving upfield): 1,1,2,2,3.
The upfield singlet sugges... |
The fundamental question is: which is more acidic, 2-pyrrolidone or 2-pyrrolidinethione?
[![enter image description here][1]][1]
[![enter image description here][2]][2]
[1]: https://i.stack.imgur.com/MI8J5.jpg
[2]: https://i.stack.imgur.com/ymR2w.png
If you took a 50-50 mixture of the two and added... |
I have a flask of silica gel connected to a flask that contains a bit of water, so when I heat the silica gel the water absorbed gets evaporated and I want it to move to the other flask, but it always condenses on the roof of the first flask, so is there any way to force the vapour to move flasks? |
My book says that on dilution, the degree of dissociation of an electrolyte increases.
Consider the reaction:
A---> C+D (Reversible reaction)
Let 'A' be the electrolyte that splits into its ions- C & D.
According to my book, on dilution, the concentration of C and D will decrease. Hence according to the Le Chatliers p... |
As I understand it, if I mix $\ce{[Ag(NH3)2]NO3}$ and $\ce{Na2EDTA}$ the silver will complex much more strongly with the EDTA than the ammonia, and the hydrogen ions will protonate the ammonia, leaving $\ce{AgEDTA^{3-} + 2NH4+ +NO3- + 2Na+}$, preventing the formation of silver nitride. Does that make sense? I'm concern... |
My book says that on dilution, the degree of dissociation of an electrolyte increases. Consider the reaction:
$$\ce{A <=> C + D}$$
Let $\ce{A}$ be the electrolyte that splits into its ions $\ce{C}$ and $\ce{D}$.
According to my book, on dilution, the concentration of $\ce{C}$ and $\ce{D}$ will decrease. Hence ac... |
In the United States, sucralose is sold under the brand Splenda. There is a liquid product with the food label shown below:
[![enter image description here][1]][1]
The low calorie sweeteners containing sucralose come in different form, and they often contain sugars with calories. Here is one example:
[![enter ... |
For what reason is it universally agreed upon that we use $$ H^++OH^-$$ ions in balancing water on either side of the reaction, but not the $$ H_3 O^+$$ ions?
|
Why do we use [H+] and [OH-] in balancing redox reactions instead of using [H3O+] and [OH-]? |
Because what we really need to know here is the concentration of *protons*. The concentration of water is considered to be constant in most of the calculations involving the water autodissociation. Thus, you may hydrate the said *proton* in your equation however you want - or not at all - but $K_w=[\text{H}^+][\text{OH... |
Because what we really need to know here is the concentration of *protons*. The concentration of water is considered to be constant in most of the calculations involving the water autodissociation. Thus, you may hydrate the said *proton* in your equation however you want — or not at all — but $K_\mathrm{w} = [\ce{H+}][... |
For what reason is it universally agreed upon that we use $$\ce{H+ + OH-}$$ ions in balancing water on either side of the reaction, but not the $$\ce{H3O+}$$ ions?
|
Why do we use [H⁺] and [OH⁻] in balancing redox reactions instead of using [H₃O⁺] and [OH⁻]? |
**TL; DR**: Yes, *perborate* and *peroxoborate* are both the same thing. *Perborate* is just more popular, but *peroxoborate* is a more literate name for the $\ce{[B2(O2)2(OH)4]^2-}$ ion.
----------
A *perborate* is a name attributed historically in XIX century to the compounds containing $\ce{BO3-}$ anion (see e... |
Please ELI5; I've never studied chemistry. I read about alkalinity v. basicity [here](https://chemistry.stackexchange.com/q/19778/7952) and on [Sciencing.com](https://sciencing.com/alkaline-vs-basic-6132782.html).
[Lemons and limes are doubtless acidic](https://www.organicfacts.net/health-benefits/fruit/differenc... |
Is it wrong to allege that lemons and limes are alkaline? |
I want to ask a question about the overlap integral.
I was studying about the MO diagram of $\ce{H_2^+}$ and we managed to derive an expression which had the following term:
$$\ce{<1S_A(r_A) | 1S_B(r_B)}>$$
and our lecturer later explained that this is known as the **overlap integral**.
> The overlap inte... |
Grouping of food items into various classes is a very old idea of Ancient Greek, Alchemists & Ancient Indian School of Medicine (Aryuveda). These ideas are perhaps thousands of years old. From a scientific perspective these classifications don't mean anything today. For example, in those schools of thought, fish has a ... |
I want to ask a question about the overlap integral.
I was studying about the MO diagram of $\ce{H_2^+}$ and we managed to derive an expression which had the following term:
$$\langle \mathrm{1s}_\ce{A}(r_\ce{A}) | \mathrm{1s}_\ce{B}(r_\ce{B}) \rangle$$
and our lecturer later explained that this is known as t... |
The figure below shows how vapor pressure of a liquid is measured. Initially the flask is at atmospheric pressure. Then the liquid is dropped in the flask. Once equilibrium is reached, the pressure from the vapor created is recorded. My question is - if the flask were initially at a different pressure - let's say 5 atm... |
Is the vapor pressure of a liquid dependent on the pressure of the atmosphere in which it is measured? |
Yes, in principle it could be different, but the effect would be small unless the increase in pressure was very large.
Let's call your liquid "$X$". At equilibrium, the chemical potential of $X_{(l)}$ equals the chemical potential of $X_{(g)}$. The pressure of $X_{(g)}$ at which that occurs is called the vapor pr... |
Yes, in principle it could be different, but the effect would be very small unless the increase in pressure were very large.
Let's call your liquid "$X$". At equilibrium, the chemical potential of $X_{(l)}$ equals the chemical potential of $X_{(g)}$. The pressure of $X_{(g)}$ at which that occurs is called the va... |
> The question proposed as the best original was useful but did not clarify my doubt completely. I am asking for the relation between the bond angles and the amount of s/p character, whereas that answer/question is about s/p character itself and doesn't derive the formula, **just uses it**.
In *Concise Inorganic Che... |
My question is: what is the best way for extraction microrna from humans plasma? Whether trizol is suitable, or i will should use commercial kits? Thanks |
Will cinnamaldehyde undergo self-aldol condensation?
[![Cinnamaldehyde][1]][1]
My book says it won't, but since it has an α-hydrogen, I'm confused.
[1]: https://i.stack.imgur.com/nhutu.png |
I got values of 5.0*10^-4, 2.5*10^-4, and 183 for the following problems; however, these seem to be inaccurate and I'm not sure what to do.
Thank you in advance!
Here is the procedure:
Obtain 6 disposable test tubes. Label the test tubes 1 through 6. To each of the 6 mm test tubes add 5.0 mL of 2.0 × 10–4 M KSCN... |
Many sources including previous answers on stack exchange, claim that it is anti aromatic.
But in a different yet similar question, I have also seen people saying that a monocyclic ring with 7 or more members can go out of plane to avoid anti aromaticity and become non aromatic.
Should'nt the same rule apply here as we... |
I am having a lot of trouble understanding the influence of volume on relative permittivity/static dielectric constant. I'm not a chemist, but am using molecular dynamics to calculate relative permittivity for use in other work.
A predecessor used this equation for relative permittivity $ε_\mathrm{r}$:
$$ε_\ma... |
It's very confusing that while $\ce{H2SO4}$ has an $n$-factor of 2, whereas $\ce{H3PO3}$ has $n$-factor 2 instead of 3. Many tried explaining it to me by molecular structures, but I don't know how to draw them. Could you please try explaining without the help of molecular structures? |
Many sources including previous answers on Stack Exchange claim that it is antiaromatic.
But in a different yet similar question, I have also seen people saying that a monocyclic ring with 7 or more members can go out of plane to avoid antiaromaticity and become non-aromatic.
Shouldn't the same rule apply here as... |
Many sources including previous answers on Stack Exchange claim that it is antiaromatic.
But in a different yet similar question, I have also seen people saying that a monocyclic ring with 7 or more members can go out of plane to avoid antiaromaticity and become non-aromatic.
Shouldn't the same rule apply here as... |
I want to reduce palladium with silver ([in cellulose](https://unblinkingeye.com/Articles/Kallitype/kallitype.html)): $\ce{Pd^{2+} + 2Ag->2Ag+ +Pd}$. What is a good ligand and spectator ion for both metals? (The pH is not critical.) Ones I have considered:
* $\ce{[Pd(H2O)4](NO3)2}$: **Unstable**; hydrolyzes to insol... |
What's an appropriate ligand for Pd-Ag redox? |
My book says that on dilution, the degree of dissociation of an electrolyte increases. Consider the reaction:
$$\ce{A(aq) <=> C(aq) + D(aq)}$$
Let $\ce{A}$ be the electrolyte that splits into its ions $\ce{C}$ and $\ce{D}$.
According to my book, on dilution, the concentration of $\ce{C}$ and $\ce{D}$ will decrea... |
I want to reduce palladium with silver ([in cellulose](https://unblinkingeye.com/Articles/Kallitype/kallitype.html)): $\ce{Pd^{2+} + 2Ag->2Ag+ +Pd}$. What is a good ligand and spectator ion for both metals? (The pH is not critical.) Ones I have considered:
* $\ce{[Pd(H2O)4](NO3)2}$: **Unstable**; hydrolyzes to insol... |
This is the plot of the Van der Waals equations:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/Dsk4h.png
As you can see, the Van der Waals equation predicts a "stretched liquid" area (MNS). Is this physically feasible and what exactly happens there? Are there any intuitive explanat... |
I have NaOH pellets at my disposal. Some of the pellets [are degraded][1], but most are not, and I can provide a new batch if needed.
I would like to test several humidity sensors in an environment with a humidity value around 10%. NaOH should be able to reach [about 7% humidity when pure][2].
How should I procee... |
How can I make a reference humidity environment with NaOH pellets? |
When explaining the mathematics behind calculating HOMO-LUMO energies using quantum chemistry, Chainer Chemistry documentation states that
> From mathematical viewpoint it requires a solution of an internal
> eigenvalue problem for a Hamiltonian matrix.
1. I have never heard of internal eigenvalue problem in m... |
Currently I studying about the Lewis dot structure for different compounds and my textbook says that the Lewis structure for ozone may be drawn as(as shown in the image):
And then it goes on to calculate the formal charges on dif... |
What is the Lewis dot structure for ozone? |
I am now confused whether solids flow or not. Some people say solidity is only a time scale notion. Some others say solids do not flow at all. While some authors say there is a threshold stress below which solids do not flow at all.
I came to know that glass do not flow which is against the common myth that old chur... |
Do solids flow? |
Why is CO2 + Ca(OH)2 an acid-base reaction? |
I want to reduce palladium with silver ([in cellulose](https://unblinkingeye.com/Articles/Kallitype/kallitype.html)): $\ce{Pd^{2+} + 2Ag->2Ag+ +Pd}$. What is a good ligand and spectator ion for both metals? (The pH is not critical.) Ones I have considered:
* $\ce{[Pd(H2O)4](NO3)2}$: **Unstable**; hydrolyzes to insol... |
Is chirality a property of molecules with exactly 1 chiral centre? |
If the $n$-factor is what I assume it is (the basicity, or ‘how many moles of sodium hydroxide can one mole of acid neutralise?’) then …
It is really hard to explain this without molecular structures. Sum formula are of little help to chemists once you reach more than four or five atoms or if there are two types of ... |
When explaining the mathematics behind calculating HOMO-LUMO energies using quantum chemistry, [Chainer Chemistry documentation](https://chainer-chemistry.readthedocs.io/en/latest/tutorial.html#homo-prediction-by-nfp) states that
> From mathematical viewpoint it requires a solution of an internal
> eigenvalue prob... |
What about this ?
$$\ce{CO2(aq) + H2O <=> H2CO3}$$
$$\ce{H2CO3 <=> H+ + HCO3-}$$
$$\ce{HCO3- <=> H+ + CO3^2-}$$
$$\ce{Ca(OH)2 <=> Ca(OH)+ + OH-}$$
$$\ce{Ca(OH)+ <=> Ca^2+ + OH-}$$
$$\ce{H+ + OH- <=> H2O}$$
$$\ce{Ca^2+ + CO3^2- <=> CaCO3 v}$$
|
In the United States, sucralose is sold under the brand Splenda. There is a liquid product with the food label shown below:
[![enter image description here][1]][1]
The low calorie sweeteners in solid (powder) form containing sucralose come in different form, and they often contain sugars with calories. Here is on... |
I know zero about chemistry, and Google has not offered up a plain answer, so I beeseech thee; Is it safe to mix calcium carbonate and sodium chloride to make a simple mouthwash? Calcium carbonate for the acid neutralizing, and sodium chloride for disinfectant. |
Is it safe to mix calcium carbonate and sodium chloride? |
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