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The electron affinity of a neutral oxygen atom is −142 kJ (it releases this energy). The electron affinity for the now anionized oxygen is 710 kJ (work must be done on the atom).
My question is, why the large jump in electron affinity? We are taught that the electrons do not interact much with each other in the way ... |
Why does oxygen not like to be doubly anionized? |
How exactly is ammonium sulfate formed in a Kjeldahl analysis? |
Is it possible to add copper nitrate solution and lead so that a single displacement reaction occurs to yield lead nitrate. I recently melted lead and added cooper nitrate to the molten lead. I then collected the copper nitrate solution I had poured and repeated the process of melting the lead and pouring the solution ... |
How will the cyclobutane ring behave in the following case?
![enter image description here][1]
[1]: https://i.stack.imgur.com/jwtlZ.png
I initially thought there would be ring expansion to a five membered ring so that there may be less angle strain and a secondary carbocation instead of a primary one. But ... |
$\Delta H$ for the reaction below is −126 kJ
$$\ce{2Na2O2(s) + 2 H2O(l) ->4 NaOH(s) + O2 (g)}$$
What is the amount of heat released by the reaction of 25.0 gram of $\ce{Na2O2}$ with water? |
We are making an electrochemical research on supercapacitors that involves checking stability of our material. That requires repeated writing of cyclic voltammetry curves. Our goal is to write at least 2000 of them, but there is a problem with Nova software (version 1.8, to be specific): if we want to write even 50 cyc... |
How do I write many cyclic voltammetry curves in Nova? |
Suppose I have the reversible reaction:
$$A+B⇌ C $$
The reaction is at equilibrium with equilibrium constat $K$
I am told that if I increase the concentration of $B$, the rate for the forwards reaction will exceed the backwards one. Fair enough.
I am also told that $K$ will necessarily increase. Why though... |
Why is ketone not capable of hydrogen bonding among themselves? |
I was looking at substances that produce the highest flame temperatures upon combustion. I note that the equations for combustion are producing carbon monoxide rather than carbon dioxide.
[1]: http://oxygen.atomistry.com/cyanogen_flame.html
$$\ce{(CN)2 + O2 -> 2CO + N2}$$
Why isn't carbon dioxide produced? W... |
Why is a ketone not capable of hydrogen bonding among themselves? |
In all the reactions I saw online, dichlorotriazine is shown to form only one bond with cellulose ([example 1][1], [example 2][2]; [paper][3]).
But cellulose has [many potential sites for bonding][4]. Can dichlorotriazine actually give up both Cl atoms for forming two bonds with cellulose?
[1]: https://en.wik... |
Can one dichlorotriazine molecule form two bonds with cellulose? |
We know from basic chemistry that a reaction reaches equilibrium as described by [Le Châtelier's principle][1]. What's the quantum mechanical explanation to this principle? How a change in temperature/concentration causes an equilibrium to shift, from the point of view of wave functions?
[1]: https://en.wikipedi... |
Quantum mechanical explanation for Le Chatelier's principle? |
Does the Battery Bounce Test actually work? |
How to figure out which solutions evolve the largest heat? |
Suppose I have the reversible reaction:
$$A+B⇌ C $$
The reaction is at equilibrium with equilibrium constat $K$
I am told that if I increase the concentration of $B$, the rate for the forwards reaction will exceed the backwards one. Fair enough.
I am also told that $K$ will necessarily increase. Why though... |
An electrolyte can be electrolysed by a voltage higher than the reverse reaction's cell potential, while conducting a current in the process. But what happens at the electrodes when the applied voltage is below this cell potential, such as below 1.23V for water or 4.07V for NaCl? Does the reverse reaction occur simulta... |
How does an electrolyte react to voltages below its electrolysis potential? |
I'm really confused about it. So I hope to ask it here to clear my doubt!.
Then let's assume that there is four pairs of solutions given
![enter image description here][1]
[1]: https://i.stack.imgur.com/BwVEQ.png.
So which would be emit more heat if mix same volumes of given pairs ? |
How to figure out which two solutions which emit largest heat when they are mixed in same volumes? |
How to figure out which two solutions will emit largest heat when they are mixed in same volumes? |
I'm really confused about it. So I hope to ask it here to clear my doubt!.
Then let's assume that there is four pairs of solutions given
![enter image description here][1]
[1]: https://i.stack.imgur.com/BwVEQ.png.
So which would be emit more heat if we mix same volumes of given pairs ? |
Bulk carbon is an insulator, but at nanoscale (e.g. carbon nanotubes) carbon may become a good electrical conductor. If I am correct this means carbon nanotube band structure is metal-like. E.g. it has partly filled valence band (like in the rightmost case in the figure below).
![enter image description here][1]
... |
Why carbon nanotubes can act as a good electrical conductor? |
This seems to be a very specific case. I would say that you should start with a standard Ni electroplating solution and see the result. You could then adjust the parameters of your plating operation and the concentrations of the additives in the solution.
However, I have a bigger concern. How stable is your liquid c... |
Carbohydrate like glucose undergoes peridic cleavage by HIO4 and forms respective products are five moles of formic acid and one mole of formaldehyde. Here is my question , what is mechanism and what are the products by fructose with the same? Do we have any specific rules for that? |
Do only outer electron shells take part in forming chemical bonds? Or could an inner shell create a bond under some conditions? |
Do only outer electron shells take part in forming chemical bonds? |
An electrolyte can be electrolysed by a voltage higher than the reverse reaction’s cell potential, while conducting a current in the process. But what happens at the electrodes when the applied voltage is below this cell potential, such as below 1.23 V for water or 4.07 V for NaCl? Does the reverse reaction occur simul... |
Carbohydrate like glucose undergoes periodic cleavage by $\ce{HIO4}$ and forms respective products are five moles of formic acid and one mole of formaldehyde.
Here is my question , what is mechanism and what are the products by fructose with the same? Do we have any specific rules for that? |
I'm really confused about it. So I hope to ask it here to clear my doubt!.
Then let's assume that there is four pairs of solutions given
![enter image description here][1]
So which would be emit more heat if we mix same volumes of given pairs ?
These are the balanced reaction occur above mixtures are mix... |
First, I’m a high school student and I wonder why every textbook just tells you how to set up those equations and cancel them to get the entropy change but never tells you why you can cancel the same species on both sides.
Second, for example,
$\ce{2B + 3H2O -> B2H6 + 3/2O2} \tag{ $\Delta H= 762~\mathrm{kJ}$}$... |
I know that most of the double displacement reactions form some kind of precipitates in their products. But do all of the double displacement reactions form precipitates? I have searched on this site as well as on Google, I've found answers, but they are not clarifying my doubts. Maybe I need a simpler explanation.
... |
I'm really confused about it. So I hope to ask it here to clear my doubt!.
Then let's assume that there is four pairs of solutions given
![enter image description here][1]
So which would be emit more heat if we mix same volumes of given pairs ?
These are the balanced reaction occur above mixtures are mix... |
I've been struggling with this problem that I can't seem to figure out. I think I know how to solve it but I think there's missing information.
>The combustion of 1 mole of glucose $\small\ce{C6H12O6}$ releases $2.82\times10^3$ kJ of heat. If 1.25 g of glucose are burnt in a calorimeter containing 0.95 kg of water a... |
How to figure out which two solutions will emit the largest heat, when they are mixed in same volumes? I'm really confused about it.
Then let's assume that there is are five pairs of solutions given:
![enter image description here][1]
So which one emits the most heat, when we mix same volumes of given pairs?... |
Will the sulfur-iodine cycle and Haber Method work at lower pressures and temperatures? |
The solution is Emerald green in colour.
When added with water, it gives a pale blue solution
When reacted with BaCl2, it gives a sky blue solution and a white precipitate.
When reacted with AgNO3, it gives a sky blue solution and a white precipitate.
This does not make any sense to me. The BaCl2 is used to te... |
The solution is emerald green in colour.
When added with water, it gives a pale blue solution
When reacted with $\ce{BaCl2}$, it gives a sky blue solution and a white precipitate.
When reacted with $\ce{AgNO3}$, it gives a sky blue solution and a white precipitate.
This does not make any sense to me. The $\ce{... |
You already determined the $\Delta S$ for benzene at 353 K by dividing the $\Delta H$ at 353 K by the temperature 353 K. Now all you need to do is determine the $\Delta H$ at 343 K using Hess' law? Once you do that, you can get the $\Delta S$ at 343 K. |
How to figure out which two solutions will emit the largest heat, when they are mixed in same volumes? I'm really confused about it.
Then let's assume that there is are five pairs of solutions given:
So which one emits the most heat, when we mix same volumes of given pairs?
These are the balanced reactio... |
I can find in literature what the density is for untreated viscose, but not for viscose that is bleached. Does this change the density? And what is the density for bleached viscose?
|
What is the rationalization for calling reactions with rates independent of pH but dependent on the concentration of a particular acid catalyst under "general" acid catalysis, and pH dependent reactions under "specific" acid catalysis ?
It would seem to me that the pH-independent reactions would be better considere... |
If you extract energy from a substrate (e.g. glucose) step-wise, a lot more free energy is released that can be used. However, if you were to do this in one single step, very little useful energy could be harnessed. Why is that? |
Why is it that less useful energy can be extracted in explosive reactions? |
What are side chain order parameters? |
Can gold recovery with ap (acid peroxide) method be done under vacuum or left in sealed chamber, as opposed to placement in open air? |
Can gold recovery with acid peroxide (ap) method be done under vacuum or left in sealed chamber, as opposed to placement in open air? |
> Dilution of the solvent adds new energy states to the liquid, but does
> not affect the solid phase.
[The above line appeared on the following page under the section "5: Colligative properties and entropy" and the last paragraph][1]
[1]:http://www.chem1.com/acad/webtext/solut/solut-3.html#SEC5
Actually,... |
Why the dilution of solvent doesn't affect the solid phase, in comparison to the liquid phase? |
An effective way to disperse rioters & looters would be to send an armored vehicle in to spray them with a very stinky liquid. Is there a chemical that stinks but is not a health risk and that breaks down after a few hours, or could be neutralized with another solution after a few hours? |
Is there a very stinky chemical solution that isn't a health hazard? |
I am looking to calculate the minimum heat needed to create vapor from a specific mixture. I have a mixture of 60 % $\ce{C3H8O3}$ (glycerine) and 40 % $\ce{C3H8O2} $ (propylene glycol, propane-1,2-diol). Total volume of the mixture is 3 ml. Here are some facts that I know
C3H802
Density = 1.04 g/cm³
... |
During a chemical reaction, equal moles of two diatomic molecules X and Y are allowed to react to form one gaseous compound XnYm. After the reaction is complete, it was observed that the density of the product formed is 1.50 greater than the density of the reactant mixture.
Here is my work:
Xm + Yn -> XnYm
... |
During a chemical reaction, equal moles of two diatomic molecules $X$ and $Y$ are allowed to react to form one gaseous compound $X_{n}Y_{m}$. After the reaction is complete, it was observed that the density of the product formed is 1.50 greater than the density of the reactant mixture.
Here is my work:
$X_{m} +... |
How does the atomic structure of crystals determines its shapes? |
That's a good, concise statement of Bent's rule. Of course we could have just as correctly said that p character tends to concentrate in orbitals directed at electronegative elements. We'll use this latter phrasing when we examine methyl fluoride below. But first, let's expand on the definition a bit so that it is cle... |
The thermodynamic definition of entropy is expressed as
$$dS = \frac{dq_{rev}}{T}$$
I understand that it depends on amount of heat transferred because heat transfer can be understood as the degree of dispersion of energy but what does the temperature dependence actually mean? |
Does vinyl or secondary butyl have higher priority, and why? |
Which has higher priority according to Cahn-Ingold-Prelog priority rules? |
Salts can bind with some water to form hydrates. For example, we can call $CoCl_2\cdot 6H_2O$ cobalt chloride hexahydrate. There is no reason that water should be the only solvent that can bind with salts though. Dimethyl sufloxide is pretty polar and can dissolve some salts, so I might hypothesize that we could make s... |
Name for analog of salt hydrate with non-water solvents? |
Does vinyl or secondary butyl have higher priority, and why?
According to my textbook, vinyl has higher priority than isopropyl, because an atom which is connected by a double bond can be treated as two identical atoms(one of them is just an imaginary atom).
How about vinyl and secondary butyl? Should the imaginary a... |
So looking at the Wikipedia pages of [sulfur tetrafluoride][1] and [silicon tetrafluoride][2], the melting points are −121 °C and −90 °C respectively, and so $\ce{SiF4}$ has the higher melting point. However, their boiling points are −38 °C and −86 °C, respectively, giving $\ce{SF4}$ the higher boiling point.
I can... |
Salts can bind with some water to form hydrates. For example, we can call $\ce{CoCl_2\cdot 6H_2O}$ cobalt chloride hexahydrate. There is no reason that water should be the only solvent that can bind with salts though. Dimethyl sufloxide is pretty polar and can dissolve some salts, so I might hypothesize that we could m... |
![enter image description here][1]
Regarding the above picture, why is the $\ce{C-C}$ $\sigma$ bond composed of two $\ce{sp^2}$ orbitals while the $\ce{C-H}$ $\sigma$ bonds composed of $\ce{sp^3}$ hybrid orbitals? I don't see why; I thought the geometry around the carbons was trigonal planar. Why does hybridizatio... |
Its all about minimizing the energy of the system. Imagine a 2D example:
![2D example][1]
You can imagine the green circles as the cations/$Na^+$ and the blue ones as anions/$Cl^-$. Where is the next chloride you add going to go?
1. Not a great choice- it doesn't really balance. The nearest blue ion is already ... |
A tertiary alcohol has a pka of 18 while a primary alcohol has a pka of 16.
Shouldn't the tertiary alcohol be more acidic since its conjugate base is more stabilized due to induction? |
What is reason tertiary alcohol pka is higher than primary alcohol pka? |
![enter image description here][1]
[1]: https://i.stack.imgur.com/FXtRw.jpg
The above are the reactions given in my book for the qualitative analysis of nitrate ion (formation of the brown ring complex). I think that the reactions above are incorrect. The first one shows formation of $\ce{Fe^3+}$ , which shou... |
- The original ["Rutgers' reference"][1] deploys $2\,\mbox{mmol}$ aldehyde in $20\,\mbox{mL}$ solvent (i.e. starting at $0.1\,\mbox{mol/L}$, or $0.1\,\mbox{M}$) and recommends a stirring of $3\,\mbox{h}$.
Subsequently, you mention $1\,\mbox{mmol}$ per $20\,\mbox{mL}$ solvent (i.e. starting at $0.05\,\mbox{M}$), but... |
I want to calculate the activity coefficients of mixed solvent salt solutions. I am seeing very strange behavior when I try calculating the activity coefficient of salts in non-polar solvents using Debye-Huckel theory though and its messing up my down-stream calculations.
In a simple example, let's compare the activ... |
A tertiary alcohol has a $\mathrm{p}K_\mathrm{a}$ of 18 while a primary alcohol has a $\mathrm{p}K_\mathrm{a}$ of 16.
Shouldn't the tertiary alcohol be more acidic since its conjugate base is more stabilized due to induction? |
What is the reason that tertiary alcohol pKa is higher than primary alcohol pKa? |
How can I figure out which two solutions will emit the largest heat, when they are mixed in same volumes?
Then let's assume that there is are five pairs of solutions given:
\begin{align}
\ce{2NaOH + H2SO4 &-> Na2SO4 + 2H2O}\\
\ce{Ba(OH)2 + H2SO4 &-> BaSO4 + 2H2O}\\
\ce{2NH4OH + H2SO4 &-> (NH4)2SO4 + 2H2O}\\
\c... |
I’m stuck on a particular problem which I can’t work my head around:
Information has been given that: The boiling point of benzene at atmospheric pressure is $353~\mathrm{K}$ and the enthalpy of vaporization of benzene is $30.8~\mathrm{kJ~mol^{−1}}$ at this temperature. The molar heat capacities of the liquid and va... |
I'm having trouble determining if sugars are D/L in their chair forms. My textbook has generously provided this image of D-Glucose. ![enter image description here][1]
[1]: https://i.stack.imgur.com/IjNqQ.png
So I know that from the fischer, when I put everything into a chair view, the things on the left point... |
How can you tell if a sugar is D/L in its chair form? |
I'm having trouble determining if sugars are D/L in their chair forms. My textbook has generously provided this image of D-Glucose. ![enter image description here][1]
[1]: https://i.stack.imgur.com/IjNqQ.png
So I know that from the fischer, when I put everything into a chair view, the things on the left point... |
There was a question in one of my exam papers to draw the resonance structures for $\ce{N2O}$. But the resonance structures I drew were not given marks.
The top 2 structures are the ones I drew and the bottom 3 are the ones in the marking scheme.
I have a doubt that whether my structures are unstable (like $\ce{N}... |
Now A transition element is one which forms one or more stable ions which have partially filled d-orbitals. Manganese (Mn) could have an oxidation state of 7+ which means that it will lose all of the $3d^5$ and $4s^2$ electrons. So how could make a 7+ ion in that case (which means that it will lose all of the $4s^2$ an... |
Between ethene and propene which is more acidic and why?If they are they are the same then why so?
I googled their pKa and both have pKa as ~44 |
Between ethene and propene which is more acidic and why? |
Between ethene and propene which is more acidic and why? If they are they are the same then why so?
I googled their $pK_a$ and both have $pK_a$ as ~44 |
The percent dissociation of a base $\ce{X}$ in a $0.002\ \mathrm{M}$ solution is $4.7 \cdot 10^{-3}\ \%$. What is the pH of the solution and what is the $\mathrm{p}K_\text{b}$ of base $\ce{X}$? The autoionization of water may not be neglected.
**Attempt at solution:** We have the following reactions: $$ \ce{X + H2O(... |
I live in the tropics, and have a water tank that sits in the sun, forming algae. Every year, I need to scrub the thing out. The plumber I’ve hired for the job wants to flush my water pipes with HCl to kill any residual algae. The pipes are mostly PVC, with braided metal hose and metal fittings here and there. Should I... |
Does HCl kill algae? |
Does vinyl or secondary butyl have higher priority, and why?
According to my textbook, vinyl has higher priority than isopropyl, because an atom which is connected by a double bond can be treated as two identical atoms (one of them is just an imaginary atom).
How about vinyl and secondary butyl? Should the imaginary ... |
Smoke alarms are a necessary part of many modern day buildings, especially in laboratories and of course, the family home.
According to the World Nuclear Association page [Smoke Detectors and Americium][1] (2014), a major part of the operation of a smoke detector is when the Americium-241 emits alpha particles colli... |
A transition element is one which forms one or more stable ions which have partially filled d-orbitals. Manganese (Mn) could have an oxidation state of 7+ which means that it will lose all of the $3d^5$ and $4s^2$ electrons. So how could make a 7+ ion in that case (which means that it will lose all of the $4s^2$ and $3... |
I was wondering about molecular orbitals of methylene different states 1B1 3B1 1A1
and how are they connected to symmetry point group lower case 1a1, etc orbitals what those numbers and alphabets mean?
it would be great if someone can derive those orbitals from symmetry and show me which states 1B1, 3B1 and 1A1 are r... |
From [this](https://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=9&ved=0CFAQFjAI&url=http%3A%2F%2Fwww.ismtii2011.org%2Farticle%2Fxml%2Fsub%2Ffile_download.kin%3Fmain_no%3D202%26mode%3Dpdf&ei=4mBDVZGhNY63uQS8toHYCQ&usg=AFQjCNH4KEifjFcA8P6pE9KxmsMyLXjbyA&sig2=hgnbBozls-uaDFqTWlOHew&bvm=bv.92189499,d.c2E&cad=rj... |
From [this](https://books.google.co.in/books?id=o-YTN9aXAeIC&pg=PA334&lpg=PA334&dq=non+ferrous+alloy+showing+martensite+structure&source=bl&ots=sNzLxrp5PF&sig=crkye7yrKb3m65JpZkdKQHTaagg&hl=en&sa=X&ei=VHJDVZSrNdOJuwTy0IHACg&ved=0CEAQ6AEwCA#v=onepage&q=non%20ferrous%20alloy%20showing%20martensite%20structure&f=false) li... |
I was wondering about molecular orbitals of methylene different states 1B<sub>1</sub> 3B<sub>1</sub> 1A<sub>1</sub>
and how are they connected to symmetry point group lower case 1a<sub>1</sub>, etc orbitals what those numbers and alphabets mean?
It would be great if someone can derive those orbitals from symmetry a... |
The energy level of a hydrogen atom in its ground state is $-13.6\ \mathrm{eV}$.
How is this value calculated and how can we calculate the same for different orbits? |
Between ethene and propene, which is more acidic and why? If they are they are the same then why so?
I googled their $\mathrm{p}K_{\mathrm{a}}$ and both have $\mathrm{p}K_{\mathrm{a}}$ as ~44. |
If we have the dissociation's energies of hydrogen molecule $\ce{H_{2}}$($D_{0}$) and the corresponding molecule ion $\ce{H_{2}^{+}}$ ($D_{1}$) together with the first energy of ionization of hydrogen atom ($E_{I}$), how can we estimate the first energy of ionization of hydrogen molecule? |
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