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I understand how the protons and electrons move around through various carriers, shuttles and proteins...But there's this talk of electrons being in "lower in energy" at the end. What does that mean? How is an electron lower in energy?
Also why do they need an electron acceptor? What would happen if there was no O2 ... |
1. What order of reactivity do you predict will b observed when each alkyl halide is mixed with sodium iodide in acetone?
1-Chlorobutane
1-Bromobutane
2-Chloro-2-methylpropane
Bromobenzene
2-Chlorobutane
1-Chloro-2-butene
2. What order of reactivity do you predict will b observed when each ... |
I read in Russian popular articles that it is allowed to preserve herring/fish with [Hexamethylenetetramine][1] in Europe. Since Soviet times, I like to buy salty herring and [marinade][2] it with Vinegar. The food-safety article says that ***Hexamethylenetetramine + Vinegar = Formaldehyde***, which is a serious poison... |
In my textbook there is the following problem:
>How many moles of $\ce{NH4Cl}$ must be added to $2.0~\mathrm{L}$ of $0.10~\mathrm{M}$ $\ce{NH3}$ to form a buffer with $pH=9$? Assume the addition does not change the volume of the solution significantly.
The solution given is as follows:
The equilibrium between ... |
1. What order of reactivity do you predict will b observed when each alkyl halide is mixed with sodium iodide in acetone?
1-Chlorobutane
1-Bromobutane
2-Chloro-2-methylpropane
Bromobenzene
2-Chlorobutane
1-Chloro-2-butene
2. What order of reactivity do you predict will b observed when each ... |
If I had a beaker of water (i.e. many molecules), at exactly 0 °C and at atmospheric pressure, what phase would be encountered?
And would the answer to this also apply to other substances at their freezing/melting point, and out of interest, would the same effect be observed at their other "phase intercepts" too? |
Compounds of silver form particularly strong bonds which is accounted for by the significant covalent character of the bonding. Furthermore, is the tendency to form covalent bonds linked to the fact that $Ag^+$ is a soft acid? |
Why does Silver form bonds with covalent character? |
In my textbook there is the following problem:
>How many moles of $\ce{NH4Cl}$ must be added to $2.0~\mathrm{L}$ of $0.10~\mathrm{M}$ $\ce{NH3}$ to form a buffer with $pH=9$? Assume the addition does not change the volume of the solution significantly.
The solution given is as follows:
The equilibrium between ... |
This weekend I accidentally left a glass of water on my kitchen table for a few days while I was out of town. Unsurprisingly, bubbles formed on the walls.
As I understand from the last time I attended a chemistry class quite a while ago, this happens due to water self-ionizing (at about a ratio of $10^{-14}$ if I ... |
Is it possible to obtain pure, precipitated iron with no oxidation by some chemical process?
Alternatively is it possible to electrically purify iron using an anode and cathode?
|
Obtain precipitated iron? |
In organic chemistry I was told that the magnesium ion which is part of Grignards is coordinated to several ether molecules. The overall structure around the magnesium is *tetrahedral*, which implies that *two* ether molecules have coordinated to the magnesium center. The professor said something about fulfilling magne... |
Does the magnesium 2+ ion prefer an octet or more? |
What are the possible resonance structures for ${ClO_2}^{-}$? Assigning one double bond to the structure makes for formal charges of O (-1) - Cl (0) = O (0) $\leftrightarrow$ O (-1) = Cl (0) - O (-1). It appears that the same set of formal charges can be achieved with two double bonds (expanding the octet on Cl to 12 e... |
After running a TD-DFT , we can calculate the HOMO-LUMO difference and then calculate the the excitation energy.
Another approach is just simply pick the energies calculated in the TD-DFT and use them.
For me the latter makes more sense as that's the reason we do TD-DFT , otherwise we could access the HOMO-LUMO d... |
Which is most reliable excitation energy: LUMO-HOMO energy or TD-DFT excitation energies? |
A problem in my textbook:
Solid $AgCl$ is placed in $1$ $L$ of $0.55$ $M$ $NaCl$. Find the mass of$AgCl$ which dissolves.
I know the method to solve the problem. But is the problem malformed? We get an answer, say $x$ grams $AgCl$ dissolves. But what if we placed less than $x$ grams solid $AgCl$ in the solution i... |
I've noticed that chalcogens never form binary acids, and instead end up like water, little to no pH value. Why is this? Or am I wrong and there's a counterexample, if so please give it. |
chalcogens as acids? |
A shortage of a given chemical (sodium thiopendal) has prompted Utah to allow [firing squads for executions](http://www.cnn.com/2015/03/23/us/utah-death-penalty-firing-squad/). This shortage is due to mostly European chemical factories [refusing to export the drug to the US](http://www.theatlantic.com/international/arc... |
Why does the US not manufacture sodium thiopental themselves? |
Here is a problem a made up:
We have some aqueous $HCl$. What is the maximum possible molarity of the HCl?
How do I solve this? I don't have any good ideas. |
What is the maximum molarity of aqueous HCl? |
I've always assumed that the bubbles formed because they're coming out of solution after the water pressure drops. Inside your plumbing, the pressure is high and the water can hold a lot of gas, and then after you pour it into the glass, the pressure is lower and you have a supersaturated solution, and the gas graduall... |
**How exactly is energy created by oxidative phosphorylation?**
Energy is "created" by the syntesis of ATP. The ATP molecule is considered an energy carrier, because it is used in other reactions as a source of energy. The released energy comes from the loss of one or two phosphate gropus to form ADP or AMP.
Reme... |
CaCO3 + 2H20 + Pb2+ -> Pb(CO3) + Ca(OH)2 + H2
Does this equation balance?
On the right you have lead with 2+ charge, whereas on the right its completely neutral. So my question is do you need to balance the charges in order to make the equation correct?
If that equation is wrong, whats the right equation? |
Does this equation balance? |
CaCO3 + 2H20 + Pb2+ -> Pb(CO3) + Ca(OH)2 + H2
Does this equation balance?
On the right you have lead with 2+ charge, whereas on the right its completely neutral. So my question is do you need to balance the charges in order to make the equation correct?
If that equation is wrong, whats the right equation?
... |
$$\ce{CaCO3 + 2H2O + Pb^{2+} -> Pb(CO3) + Ca(OH)2 + H2}$$
Does this equation balance?
On the right you have lead with 2+ charge, whereas on the right its completely neutral. So my question is do you need to balance the charges in order to make the equation correct?
If that equation is wrong, whats the right e... |
> 1. What order of reactivity do you predict will be observed when each alkyl halide is mixed with sodium iodide in acetone?
>- 1-Chlorobutane
- 1-Bromobutane
- 2-Chloro-2-methylpropane
- Bromobenzene
- 2-Chlorobutane
- 1-Chloro-2-butene
I know that $\ce{I-}$ is the best leaving group, followed by $\ce{Br-}$... |
I had following question on my quiz and but I answer it wrong because I can't seem to solve it. It is related to finding equilibrium constant.
Question:
For the following reaction, at 1 bar and 300 K, partial pressures of NO2 and N2O4 are both 0.5 bar. If pressure is increased to 2 bar (this is the final pressure),... |
> I […] can't help wondering why USA […] can not manufacture this chemical themselves.
**They can and they did!**
Back in the nineteen thirties, *Ernest H. Volwiler* and *Donalee L. Tabern* filed a couple of patents on sedative thiobarbituric acid derivatives for the Illinois-based *Abbott Laborato... |
I had following question on my quiz and but I answer it wrong because I can't seem to solve it. It is related to finding equilibrium constant.
Question:
For the following reaction, at $1~\mathrm{bar}$ and $300~\mathrm{K}$, partial pressures of $\ce{NO2}$ and $\ce{N2O4}$ are both $0.5~\mathrm{bar}$. If pressure is i... |
How to find partial pressures from a given equilibrium constant Kp? |
> I […] can't help wondering why USA […] can not manufacture this chemical themselves.
**They can and they did!**
Back in the nineteen thirties, *Ernest H. Volwiler* and *Donalee L. Tabern* filed a couple of patents on sedative thiobarbituric acid derivatives for the Illinois-based *Abbott Laborato... |
Are there any fuel-air bombs / thermobaric weapons that utilise ammonium nitrate as a fuel?
I know that BLU-82 is often mistakenly referred to as fuel-air bomb, so I became curious as to whether or not there were any *actual* fuel-air bombs that used ammonium nitrate. |
Consider:
![enter image description here][1]
So, the reaction of nitric acid with sodium hydroxide and zinc oxide is simple because I know that acid + base = salt + water. Therefore:
![enter image description here][2]
It makes sense. In the second part for example, ZN is 2+ and H is -1 so using the criss-... |
How do I write out a chemical reaction? |
> How am I supposed to know this equation?
You have to *memorise* it. In aqueous solution, $\ce{NH3}$ deprotonates a small fraction of the water to give ammonium and hydroxide
$$
\cee{NH3 + H2O <=> NH4+ + OH−} \, ,
$$
and while it is usually impossible to isolate $\ce{NH4OH}$ itself, the above mentioned ... |
> In the second part for example, ZN is 2+ and H is -1 so using the criss-cross method, you get ZN(NO3)2 and water. I understand this.
I don't agree on the -1 for hydrogen, let's look again at that example:
$$\ce{2HNO3(aq) + ZnO(s) -> Zn(NO3)2(aq) + H2O}$$
**Metal oxides**, such as zinc oxide, **are basic anhy... |
I am writing my bachelor thesis about alternative materials for feminine hygiene products and for testing I need to know what the viscosity is of menstruation blood. Can I use water as replacement for menstruation blood because this kind of blood exists out of a big part of water? And what is the composition of menstru... |
What is the viscosity of menstruation blood? |
It is difficult to give a typical value as the composition and hence the physical properties of menstrual blood varies over the course of a woman's period. [This reference][1] has a good discussion which you may find useful; you can find on p. 159:
> It is fair to say that a large proportion of menses samples are co... |
I notice that Gd has a second ionization potential which is significantly higher than would be expected from the general trend in the lanthanides (see [this paper p. 945 for a graph][1]). What is the reason for this effect ?
The transition corresponds to $[Xe] 4f^{7} 5d^{1} 6s^{2} => [Xe] 4f^{7} 5d^{1}$. I understa... |
Consider:
![enter image description here][1]
So, the reaction of nitric acid with sodium hydroxide and zinc oxide is simple because I know that acid + base = salt + water. Therefore:
![enter image description here][2]
It makes sense. In the second part for example, ZN is 2+ and H is -1 so using the criss-... |
I know how to derive the expression for the equilibrium constant starting from $dG=0$,
$$\ln(K)=-\frac{\Delta g ^o}{RT}$$
However, if we are not at equilibrium, $dG$ is not necessarily zero. In this case:
$$\frac{\partial g}{\partial \epsilon} = \sum \mu_i \nu_i = \Delta g ^o + RT \ln \left( \prod a_i ^{\nu_i} \ri... |
I know how to derive the expression for the equilibrium constant starting from $dG=0$,
$$\ln(K)=-\frac{\Delta g ^o}{RT}$$
However, if we are not at equilibrium, $dG$ is not necessarily zero. In this case:
$$\frac{\partial g}{\partial \epsilon} = \sum \mu_i \nu_i = \Delta g ^o + RT \ln \left( \prod a_i ^{\nu_i} \ri... |
Chalcogens' hydrides as acids? |
I know how to derive the expression for the equilibrium constant starting from $dG=0$,
$$\ln(K)=-\frac{\Delta G ^o}{RT}$$
However, if we are not at equilibrium, $dG$ is not necessarily zero. In this case:
$$\frac{\partial G}{\partial \epsilon} = \sum \mu_i \nu_i = \Delta G ^o + RT \ln \left( \prod a_i ^{\nu_i} \ri... |
The Frost diagram for sulfur shows the relative stability (in terms of cell potentials) of the possible aqueous oxidation states. What is the reason for the instability of higher oxidation states in the acidic regime and their stability in the basic regime ? Something I have always noticed but never been able to apply ... |
An initial concentration of biomass is represented by the density of wood as:
$$700\; kg/m^3$$
If that biomass is assumed to be beech wood, it's ultimate analysis is (by weight):
$$C=49.05\%,\; H=5.83\%,\; O=45\%,\; N=0.12\%\;$$
Using the ultimate analysis values and the molecular weight of each element, a represe... |
$$NaCl+H_2SO_4 \to NaHSO_4 + HCl$$
The above reaction happens, but why doesn't the following happen? Or does it but only when one of the reactants is in excess?
$$2NaCl+H_2SO_4 \to Na_2SO_4 + 2HCl$$
The second reaction seems plausible to me. How can I predict whether a similar type of reaction will be like the... |
After creating a solution of copper(II)-sulfate-pentahydrate, water and concentrated ammonia, the newly formed complex (tetraamminecopper(II)-sulfate-monohydrate) is completely dissolved in water. By adding ethanol, one is able to decrease the solubility of that complex in water and have crystals percipitates out of so... |
An initial concentration of biomass is represented by the density of wood as:
$$700\; kg/m^3$$
If that biomass is assumed to be beech wood, it's ultimate analysis is (by weight):
$$C=49.05\%,\; H=5.83\%,\; O=45\%,\; N=0.12\%\;$$
Using the ultimate analysis values, the molecular weight of each element, and assuming... |
I am finding different equations for the synthesis. My lecture handout suggests a reaction with Sodium tetrafluroborate and Sulfuric acid. This is fine but I have to remember this for an exam and that reaction looks extremely hard to remember/balance in an exam. A second way seems to be reaction of boron oxide with Cal... |
I am finding different equations for the synthesis. My lecture handout suggests a reaction with Sodium tetrafluroborate and Sulfuric acid. This is fine but I have to remember this for an exam and that reaction looks extremely hard to remember/balance in an exam. A second way seems to be reaction of boron oxide with Cal... |
An initial concentration of biomass is represented by the density of wood as:
$$\cee{700 kg/m^3}$$
If that biomass is assumed to be beech wood, it's ultimate analysis is (by weight):
$$\ce{C}=49.05\%,\; \ce{H}=5.83\%,\; \ce{O}=45\%,\; \ce{N}=0.12\%$$
Using the ultimate analysis values, the molecular weight of each... |
Why does $H_2Se$ have a bigger $Ka_2$ than both $H_2S$ and $H_2Te$? |
Why does $\ce{H2Se}$ have a bigger $K_\text{a2}$ than both $\ce{H2S}$ and $\ce{H2Te}$? |
An initial concentration of biomass is represented by the density of wood as:
$$\cee{700 kg/m^3}$$
If that biomass is assumed to be beech wood, its ultimate analysis is (by weight):
$$\ce{C}=49.05\,\%,\; \ce{H}=5.83\,\%,\; \ce{O}=45\,\%,\; \ce{N}=0.12\,\%$$
Using the ultimate analysis values, the molecular weight ... |
> Would adding some organic phase like petrol ether or a non-soluble solid such as ceramic pellets do the same?
No. But adding other organic solvents which are miscible with water would.
The idea behind the "trick" is to reduce the polarity of the **aqueous** phase. With other words, you're making water more etha... |
Is it possible to chemically convert Methane into Propane? If so what is involved and is it economical.
Thanks,
Brad |
Yes, it can be done by mimicking the conditions in the earth's mantle.
It was shown by *Alexander Goncharov* and coworkers by placing methane in a diamond anvil cell, applying a pressure of more than 2 GPa and heating everything to a temperature around 1000-1500 K with a laser. ([Source](http://dx.doi.org/10.1038/ng... |
Is it possible to chemically convert Methane into Propane? If so what is involved and is it economical?
Thanks. |
An initial concentration of biomass is represented by the density of wood as:
$$\cee{700 kg/m^3}$$
If that biomass is assumed to be beech wood, its ultimate analysis is (by weight):
$$\ce{C}=49.05\,\%,\; \ce{H}=5.83\,\%,\; \ce{O}=45\,\%,\; \ce{N}=0.12\,\%$$
Using the ultimate analysis values, the atomic weight of ... |
In titrating 25 mL of a 0.2 M weak acid, HA, with 0.5 M of a strong base, say NaOH, the equivalence point is reached after 10 mL of base is added. I can calculate the pH by first setting up an ICE table to calculate the moles of A- remaining at the equivalence point, and then setting up an additional ICE table for the ... |
How can I determine the pH of a solution when I add more analyte after the equivalence point? |
Are the thermal decomposition products of polyurea polymers known, especially of the urea group, in the absence of water?
Looking at the formula
R-NH-C=O
|
HN-R
there appears to be no obvious candidate for a decomposition product - not enough oxygen for CO2, not enough hydrogen for Ammonia... |
Thermal decomposition products of polyurea? |
Are the thermal decomposition products of polyurea polymers known, especially of the urea group, in the absence of water?
Looking at the formula
R-NH-C=O
|
HN-R
there appears to be no obvious candidate for a decomposition product - not enough oxygen for CO<sub>2</sub>, not enough hydrogen ... |
For the (E)-2-pentene, there was no C=C reading, about 1600. For the (Z)-2-pentene, there is a C=C. Why is there a reading on the Z but not on the E? |
In infrared spectroscopy, why is there no C=C reading for E alkenes? |
I've noticed that chalcogens never form binary acids, and instead end up like water, with very little acidity. Why is this? Or am I wrong and there's a counterexample, if so please give it. |
while comparing the relative stabilities of acetic acid and formic acid why don't we consider the 3 possible hyper conjugative structures which would stabilize the positive charge on carbon thus making conjugate of acetic acid more stable.
My professor told me hyper conjugation does not operate here. But whats the r... |
hyper conjugation in acetic acid? |
At the beginning of a Weak Acid/Strong Base titration curve there is a sharp decrease in [H+] and a sharp increase in pH before the ratio between the weak acid and it's conjugate base becomes low enough that we have a buffer solution.
![enter image description here][1]
![enter image description here][2]
What's hap... |
What's happening at the beginning of a weak acid titration? |
At the beginning of a Weak Acid/Strong Base titration curve there is a sharp decrease in $[\ce{H+}]$ and a sharp increase in pH before the ratio between the weak acid and it's conjugate base becomes low enough that we have a buffer solution.
![enter image description here][1]
![enter image description here][2]
Wha... |
Why is p-Methoxyphenol more acidic than p-Methylphenol?
According to me, inductive effect really doesn't matter at para positions and p-Methoxyphenol should be less acidic due to the high mesomeric effect of the $\ce{-OCH3}$ group in comparison to the weak hyperconjugative effect of the $\ce{-CH3}$ group.
[p-Meth... |
Why is p-Methoxyphenol more acidic than p-Methylphenol? |
I'm reading about water models and their dispersion coefficients, and going back to S. C. Wang's work according to the citation of an equation (Google books [here](https://books.google.co.uk/books?id=Apyi_FXKnSkC&lpg=PA236&ots=3R_BmUrJsx&dq=s%20c%20wang%20u(r)%20c6r%206&pg=PA236#v=onepage&q=s%20c%20wang%20u(r)%20c6r%20... |
Why are C6 dispersion forces named C6? |
I'm reading about water models and their dispersion coefficients, and going back to S. C. Wang's work according to the citation of an equation (Google books [here](https://books.google.co.uk/books?id=Apyi_FXKnSkC&lpg=PA236&ots=3R_BmUrJsx&dq=s%20c%20wang%20u(r)%20c6r%206&pg=PA236#v=onepage&q=s%20c%20wang%20u(r)%20c6r%20... |
For an experiment, I'm adding several substances (as powders) to hydrogen chloride, and measuring the temperature changes to calculate enthalpy. What is a container I could perform it in (other than a styrofoam cup) that would minimise the heat lost to the surroundings?
I looked up using a vacuum flask of some sort... |
How to lose as little heat as possible to the surroundings from an endothermic reaction? |
1. What is the scale?
2. What is the budget?
[Reactors are available](http://shop.faust.ch/QSRCH.HTM?UID=550055125b5d000000000000&KEYVAL=9.142+106) from 250 mL up.
It might be cheaper to place a flask in a cut-off bottom of a suitable PE bottle and insulate it with PU foam from a DIY market.
|
We will be buying methanol by a about 200 liters at a time, I was wondering what I should consider when storing it.
So far I know that it should be
- in the shade
- earthed with a copper stake
- in a secondary plastic container
- wash empty containers and drain them
But I am wondering what else should... |
I'm reading about water models and their dispersion coefficients, and going back to S. C. Wang's work according to the citation of an equation (Google books [here](https://books.google.co.uk/books?id=Apyi_FXKnSkC&lpg=PA236&ots=3R_BmUrJsx&dq=s%20c%20wang%20u(r)%20c6r%206&pg=PA236#v=onepage&q=s%20c%20wang%20u(r)%20c6r%20... |
1. What is the scale?
2. What is the budget?
[Reactors are available](http://shop.faust.ch/QSRCH.HTM?UID=550055125b5d000000000000&KEYVAL=9.142+106) from 250 mL up.
It might be cheaper to place a flask in a cut-off bottom of a suitable PE bottle and insulate it with PU foam from a DIY market.
**UPDATE**
... |
In the uncertainty principle , whats the significance of the inequality sign ?
Why is it not equal to over there ?
Why do we say greater than equal to instead of just equal to ?
|
I'm reading about water models and their dispersion coefficients, and going back to S. C. Wang's work according to the citation of an equation (Google books [here](https://books.google.co.uk/books?id=Apyi_FXKnSkC&lpg=PA236&ots=3R_BmUrJsx&dq=s%20c%20wang%20u(r)%20c6r%206&pg=PA236#v=onepage&q=s%20c%20wang%20u(r)%20c6r%20... |
There's a [murder trial ongoing in Ireland at the moment][1] and one of the pieces of evidence is a spade found at the scene along with the skeletal remains. It was contended by the prosecution that this spade was belonging to the defendant but while they were similar
> "forensic evidence found the paint splatters o... |
Can weathering change the composition of something so that it appears different? |
There's a [murder trial ongoing in Ireland at the moment][1] and one of the pieces of evidence is a spade found at the scene along with the skeletal remains. It was contended by the prosecution that this spade was belonging to the defendant but while they were similar
> "forensic evidence found the paint splatters o... |
Can someone of you tell me, which of the following terms should be used or avoided? (Google shows the presence of all the candidate terms.)
- synthesis route
- synthetic route
- route of synthesis
- synthesis pathway
- synthetic pathway
Imagine for example a sentence such as "A new ... was developed." |
To start off, all chalchogens are knowns to form binary hydrides of the form $\ce{H2X}$ which can then behave as binary acids, however weak or strong, by the equation $\ce{H2X -> HX^- + H+}$.
Now to compare the strength of the acids. The most straightforward way of doing this is comparing gas phase acidities, which... |
2-Chloro-3,3-dimethylbutane or 3-Chloro-2,2-dimethylbutane...
My teacher first one is correct but why is the second one not correct in terms of locant rule ?? Pls help |
To start off, all chalcogens are knowns to form binary hydrides of the form $\ce{H2X}$ which can then behave as binary acids, however weak or strong, by the equation $\ce{H2X -> HX^- + H+}$.
Now to compare the strength of the acids. The most straightforward way of doing this is comparing gas phase acidities, which ... |
2-Chloro-3,3-dimethylbutane or 3-Chloro-2,2-dimethylbutane...
My teacher first one is correct but why is the second one not correct in terms of locant rule ?? Pls help![enter image description here][1]
[1]: https://i.stack.imgur.com/n3s0A.jpg |
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