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Can a battery powered by Iron and Air really provide a feasible power source for automobiles? |
I'm referring to the Shuttle Battery recently announced (read more on it [here](http://www.connexxsys.com/en/en_shuttle.html)) that suggests that:
> The energy density of the device is up to 7,700 Wh/L. It is more than 5 times
higher than state-of-the-art (SOA) Li-ion (550Wh/L), and comparable to fossil
fuel (10... |
Can a battery powered by iron and air really provide a feasible power source for automobiles? |
In [this paper][1] on page 1985 they say:
>Fluorescence analysis confirmed that enhanced protein binding
at higher electron dose depends only to a small extent on the
slight increase in the lateral dimensions of the nanodeposits but
to a much larger degree on their height (Figure 4E).
and:
![ente... |
Both have a carbonyl group. Since the carbonyl group of ketone is between alkyl groups it would be difficult for it to form hydrogen bonds compared to aldehydes.Then, aldehydes should have a higher boiling point compared to ketones. Why is it the other way? |
Why is the boiling point of aldehydes less than that of ketones? |
I have been going through reduction of aldehydes uding LiAlH4 and NaBH4. If there is a double bond in the compound LiAlH4 doesn't affect it but in 40% of the reduced product using NaBH4 the double bond too will be reduced.Why is it so?
I know that LiALH4 produces hydrogen in a controlled manner and nothing more abou... |
Why NaBH4 affects double bonds while LiALH4 doesn't? |
It is well known that the usage of the Gaussian basis set, in contrast to Slater basis set, leads relative simple semi-analytical expressions for the two electron repulsion integral $(ab|cd)$. Could you propose any other basis sets allowing simple computations of two-electron integrals? This is quite general questions ... |
I have been going through reduction of aldehydes uding $\ce{LiAlH4}$ and $\ce{NaBH4}$. If there is a double bond in the compound $\ce{LiAlH4}$ doesn't affect it but in 40% of the reduced product using $\ce{NaBH4}$ the double bond too will be reduced.Why is it so?
I know that $\ce{LiALH4}$ produces hydrogen in a cont... |
I use filtered water to make my coffee.
If I mix a few drops of said coffee with our tap water, it turns a grayish color; it's much darker than the coffee would turn the water by itself (I compared by doing a side by side comparison and adding an equal amount of coffee to filtered water, resulting in a much lighter ... |
Can you split carbonate ions into their constituent elements? (or at least into Carbon monoxide (not carbon dioxide) and oxygen?)
<img src="https://i.stack.imgur.com/pQShX.png" width="130" height="100">
|
Split carbonate ions? |
To extract essential oils from plant matter (amongst other purposes), steam distillation is often used. I've seen a lot of different glassware setups for this. I've sometimes seen them broken into two categories:
* Internal steam distillation
* External steam distillation
Here's my (admittedly shaky) understandi... |
My question is related to the edge between Subatomic Physics and Chemistry, but I decided that here is the best place to discuss it.
As we all know, Theoretical Physics is a well developed field of knowledge, able to describe the very tiny forms of interactions. However, after some researches for some kind of **for... |
My question is related to the edge between Subatomic Physics and Chemistry, but I decided that here is the best place to discuss it.
As we all know, Theoretical Physics is a well developed field of knowledge, able to describe the very tiny forms of interactions. However, after some researches for some kind of **for... |
Are there any two distinct types of atom or molecule that have identical emission or absorption spectra? |
Are there any molecules with the same spectrum? |
Isoelectric pH of colloids? |
Can you split carbonate ions into their constituent elements? (or at least into Carbon monoxide (not carbon dioxide) and oxygen?)
<img src="https://i.stack.imgur.com/pQShX.png" width="130" height="100">
(edit:)
I know that when running electricity through an aqueous solution containing carbonate ions and othe... |
I have a question about electrolysis. How do we know what will be on anode and cathode if we have for example NaCl diluted in water. How do we know if it's gonna be Na+ or H+?? |
So, I lately asked this question:
Is a pH value outside 0 - 14 possible?
My teacher responded with: yes, it is, but very difficult to achieve.
Then on the internet, I found multiple answers, one saying it is but because of a fault in the pH glass measurer we cant be sure, the other said that it is not possible becau... |
I'm going to be aliquoting out ethanol-stabilized chloroform into smaller containers. It's presently in a large bottle sealed with a rubber(y) sheet so I can only draw it out with a needle.
My question is:
How do I seal them?
- If I'm aliquoting to minimize exposure of the full bottle to air, can I get rid of the ... |
As transition elements have partially filled d orbitals
we also know that when electron jump from one orbital to another light is emited due to which the compounds of transion elements are seemed to be colour coppounds.
Satisfied?
03469099784 |
To understand the commonly quoted magnetic values of coordination complexes (central ion) we use
$$m_l=\sqrt{n(n+2)} \text{BM where BM}=\frac{e\hbar}{2m_e}\text{JT}^{-1}$$
$n$=number of unpaired electrons.
> ***How did we derive this equation?***
I know the orbital angular momentum of electron is given by... |
To explain the [characteristic X-ray][1] emission peaks for various elemental targets, a formula was developed which was similar in construct to the rydberg equation for H-atom as derived by the Bohr-model.
$$\bar \nu=R(\frac{1}{n_f^2}-\frac{1}{n_1^2})(Z-\sigma)^2$$
where $\bar \nu$ is the wave number, $\sigma=... |
I'm having difficulty understand the relative stabilities of these compounds
1,1-diisopropylethene < (Z)-1,2-diisopropylethene < (E)-1,2-diisopropylethene
The compounds are listed in order of increasing stability.
Also, what does the C=C-C bond angle have do to with stability? |
I've been researching sodium polyacrylate, which normally comes as those "aqua gems" for plants, or fake snow. Specifically, I've been hoping to find information on molding, casting, or otherwise giving shape to the material - nothing terribly complex, just things like simple stars for example (while hoping no one mist... |
Molding/shaping sodium polyacrylate? |
Can these changes be reversed by changing temperature? |
What are the crystallisation conditions for Equine Myoglobin?
I've tried repeating some from the PDB but no success.
|
What conditions to use to crystallise Equine Myoglobin? |
On the periodic table, period 2 and 3, 4 and 5, 6 and 7 and so on have similar blocks, identical length and groups. What are such pairs of analogous periods called? |
Hi im searching for atmospheric data on the following:
Air quality, Dust Particle Concentration, Pollution, Average Temperature etc
for various cities such as Frankfurt, London, Hong Kong, Bangkok...
Are there any websites that can give me this data (or similar atmospheric measurements) for each city? |
Can you split carbonate ions into their constituent elements **directly** in the carbonate form? (so not first producing CO2 and then decomposing the carbon dioxide)
<img src="https://i.stack.imgur.com/pQShX.png" width="130" height="100">
(edit:)
I know that when running electricity through an aqueous solutio... |
How do I keep hydrogen or oxygen in a test tube when pulling them out of water? I have a styrophome cup with two metal thumbtacks pushed though the bottom and about 100 ml of distilled water mixed with 6 grams of Sodium Hydroxide in the cup. the cup is setting on a 9 volt battery which separates the hydrogen and oxygen... |
How do I keep hydrogen or oxygen in a test tube when pulling them out of water? I have a styrofoam cup with two metal thumbtacks pushed though the bottom and about 100 ml of distilled water mixed with 6 grams of sodium hydroxide in the cup. The cup is setting on a 9 volt battery which separates the hydrogen and oxygen ... |
How do I keep hydrogen or oxygen in a test tube when pulling them out of water? I have a styrofoam cup with two metal thumbtacks pushed though the bottom and about 100 ml of distilled water mixed with 6 grams of sodium hydroxide in the cup. The cup is setting on a 9 volt battery which separates the hydrogen and oxygen ... |
I was wondering if anyone had any experience with PFBS or PFOS (perflurooctane sulfonic acid)?
I am thinking about trying to purchase some of these fluorosurfactants in bulk in order to (hopefully) use as a solvent. However, I have read that PFOS is now banned due to the bad effects on people's health and the environ... |
It seems that all wave functions studied in physical chemistry are orthogonal (e.g. particle in a box, hydrogen atomic orbitals). Does this come about because we purposefully make them orthogonal, or are they derived that way naturally? Can there be useful wave functions that are not orthogonal?
Thank you! |
Why are wave functions orthogonal? |
Anaerobic digestion and methanisation of organic feedstocks is a complex series of processes that result in biogas. One way to look at this is a very top-down, stociometric approach as in the Buswell equation
$$
C_aH_bO_c + (a-\frac{b}{4}-\frac{c}{2})H_2O \rightarrow (\frac{a}{2}+\frac{b}{8}-\frac{c}{4})CH_4+(\frac{a... |
When and how in anaerobic digestion is water dissociated? |
Charcoal (also activated charcoal) is known to adsorb a huge variety of substances including a variety of paints, dyes and many different kinds of ions. Moreover, the amount of adsorption at normal pressure and temperature is high. I know physisorption requires high capacity of Van-der-waal bonding with the adsorbate w... |
Why is Charcoal such an excellent adsorbent? |
I was reviewing the thermodynamics of micelle formation from the [Wikipedia page][1] and [this book][2]. I understood most of the arguments but micellization is supposed to be an entropy driven process with a positive entropy change in the process of micellization. But isn't this a bit counter-intuitive?
> In t... |
Thermodynammics (Entropy change) of micellization? |
It seems that all wave functions studied in physical chemistry are orthogonal (e.g. particle in a box, hydrogen atomic orbitals). Does this come about because we purposefully make them orthogonal, or are they derived that way naturally? Can there be useful wave functions that are not orthogonal? |
Is it not just because of the fact that $[aa|bb]$ is in chemists notation, meaning that $[aa|bb] = [a(1)a(1)|b(2)b(2)]$ and so you can just switch them around? |
Assume that we have a space with just two H atoms and their distance to each other is $d$. Let's say they don't have initial velocity. What is the force they will act to each other?
This question might have some mistakes in itself. But, the main thing I'm trying to learn is how an atom of element $X$ interact with a... |
How This Hydrogen Atoms Will Interact? |
How much explosive is Chlorine Methane substitution reaction in direct sunlight is it able to cause any injury? |
Why do some solutions not making any injuries at pH 2 while HCl does? |
what are the Difference between various solutions at pH <2 towards injury? |
Injury is not solely related to how strongly acidic a solution is, as there are several mechanisms by which organic matter is damaged from exposure to acids, not just protonation. It is also highly dependent on the type and length of exposure. Aqueous $\ce{HF}$ is likely considerably corrosive after skin contact even a... |
I'm new to chemistry stack exchange(not stack exchange) so please bear with any mistake regarding tags and anything else...
So my teacher gave me a shortcut regarding calculation of resultant pH if the solutions are mixed and if the difference between the pH of individual solutions is 1.
(i)if there are two solutio... |
Why this shortcut always works (proof required)? |
My teacher explained it as restricted rotation between the double bonds. But I think there is more to it. After all, what is the basic need to mark it as a type of isomerism itself? Cis trans only depends on how you make the structure on paper. So what is the basic idea behind it? |
What is the actual reason for geometrical isomerism? |
What does "Anal. Calcd." stand for written out? |
A mixture weighing $4.08g$ of $\text{BaO}$ (molar mass of $\text{Ba}$ = $138g mol^{-1}$) and an unknown carbonate $\text{XCO}_3$ was heated strongly. The residue weighed $3.64g$. This was dissolved in $100ml$ of $1M\;\text{HCl}$. The excess acid required $16ml$ of $2.5M\;\text{NaOH}$ solution for complete neutralizatio... |
What are the safety concerns with performing a chlorine methane substitution reaction in direct sunlight? |
Assume that we have a space with just two $\ce{H}$ atoms and their distance to each other is $d$. Let's say they don't have initial velocity. What is the force with which they will act on each other?
This question might have some mistakes in itself, but the main thing I'm trying to learn is how an atom of element $X... |
How will these hydrogen atoms interact? |
For example, why do some solutions not cause any injuries at pH 2 while HCl does? |
What are the properties of various solutions at pH <2 that may cause injuries? |
My teacher gave me a shortcut regarding calculation of resultant pH if the solutions are mixed and if the difference between the pH of individual solutions is 1.
1. If there are two solutions, the pH is their mean - 0.24.
2. If there are three solutions, mean + 0.56.
But what is the logic behind it? |
Why does this shortcut work for calculating pH (proof required)? |
What technology has the radioisotope Cobalt 60 replaced in medicine?
E.g.,PET preferred over CT scans |
Ok, so let's say I have raw silver which is polluted with a bit of gold, copper and lead.
So through electrorefining I want to make pure silver out of it.
Let's say I have it all in an acidic solution. What happens when I turn on the Voltage?
How would I prevent the other elements from getting electrolyzed?
Becau... |
So a teacher at school told me that strong acids do not create an equilibrium in general, while weak acids do (thats the difference, strong acids namely ionize completely). However, I lately stumbled upon a passage reporting that when experimenting with extreme pH, so extreme concentrations of acids, strange things sta... |
When we want the bad smell in toilet to go away we use a toilet spray to clean the air.
But does it really cleans it, or just the elements in that spray have better effect on our smell sense. And we think that the bad smell went away while it is not, and the air contains a mix of bed and good smells? |
![enter image description here][1]My teacher explained it as restricted rotation between the double bonds. But I think there is more to it. After all, what is the basic need to mark it as a type of isomerism itself? Cis trans only depends on how you make the structure on paper. So what is the basic idea behind it?
... |
I need some help here.
--
The figure is a portion of the titanium copper phase diagram for which only single-phase regions are labeled. Specify all temperature composition points at which eutectics, eutectoids, peritectics and congruent phase transformations occur.
I _think_ i've found the eutectic and congrue... |
I conducted a lab in which different concentrations of HCl were used and Sodium Carbonate was added. The pressure change was measured for a reaction with the different concentrations.
Now I am going to find the reaction rate for the reactions. I am thinking that using the pressure data, I can find the reaction rate... |
![enter image description here][1]
It's from the start of part 3 / chapter 19 in Lewin's Genes X (see [this page in Google Books][2])...
Looks a bit like a Ramachandran plot(?) but the axes only go to 100 / 70ish, but I don't even know what molecule it is since it doesn't say and there's no image attribution page... |
Can anyone identify this uncaptioned diagram? |
The figure is a portion of the titanium copper phase diagram for which only single-phase regions are labeled. Specify all temperature composition points at which eutectics, eutectoids, peritectics and congruent phase transformations occur.
I _think_ i've found the eutectic and congruent point. (aprox 960 and 980 ce... |
Some toilet sprays can be classed as deodorizers (or air sanitizers in the US?), while others call themselves air fresheners. So it may depend on which brand you are using, but generally the deodorizer spray is working a little harder than the air freshener.
Odor control products can work through a number of diffe... |
What triggers sodium to convert from elemental Na to Na+? I know that it wants to have a full valence shell and all that, but how does it just eject the electron out? |
What prompts sodium to give up an electron? |
Thermodynamics (Entropy change) of micellization? |
How could you test that there's oxalic acid in potatoes.For example,
> what chemical reacts to oxalic acid and then what will happen if it
> reacts? |
What is the group number or name for elements between group 3 and 4 (F-block) on the periodic table? I noticed when I look at a periodic table of elements, the elements of the F-block between group 3 and 4 doesn’t have a group number. Are they just refer as Lanthanide,and Actinide or Inner Transition Elements, But ... |
What is the group number or name for elements between group 3 and 4 (F-block) on the periodic table? |
What explains why electronegativity increases as you move across a period? Does it have something to do with the shielding effect of added electrons? |
>The electronegativity is the tendency of an atom or a functional group to attract electrons (or electron density) towards itself.
This is because the attraction of bonding electrons by an atom increases with nuclear charge (Atomic Number) and decrease of atomic radius. Both these factors operate as we move to the r... |
What pressure difference must be generated across the length of a $15$ cm vertical drinking straw in order to drink a water-like liquid of density $1.0$ g cm$^{−3}$?
I am really unsure how to proceed on this one. I was thinking of using the ideal gas law for the air inside the straw initially, and then to increase ... |
What pressure difference is needed across the length of a $15$ cm vertical drinking straw in order to drink a liquid of density $1.0$ g cm$^{−3}$? |
There is supposedly a joke shown in this picture relating to periodic trends.
Does anyone know what it is? And could they also explain where the elements on the eye exam came from?
![The joke][1]
[1]: https://i.stack.imgur.com/z0QYZ.png |
What is the joke that is shown in this picture? |
Why does electronegativity increase across a period? |
I have been given pK values of a-amino group , a-carboxyl group and side chain of Cysteine.
How can I find the ionic charge on it at different pH ? |
How to calculate charge from pK? |
I want to do some spectrometry experiments with glow in the dark paints. The red paints I've read product details for all seem to require a uv light to charge. Are there any red glow in the dark paints that can be charged with visible light?
I was also wondering why most red fluorescent pigments don't have the abili... |
For this you can use the [Henderson-Hasselbalch equation][1]. Using the degree of dissociation, $\alpha$, this can be written as
$$pH=pK_a+\log\frac{\alpha}{1-\alpha}$$
Rewriting to solve for $\alpha$:
$$\alpha=\frac{1}{10^{~pK_a-pH}+1}$$
As stated above, $\alpha$ is the degree of dissociation, meaning the degree a... |
For this you can use the [Henderson-Hasselbalch equation][1]. Using the degree of dissociation, $\alpha$, this can be written as
$$pH=pK_a+\log\frac{\alpha}{1-\alpha}$$
Rewriting to solve for $\alpha$:
$$\alpha=\frac{1}{10^{~pK_a-pH}+1}$$
As stated above, $\alpha$ is the degree of dissociation, meaning the degree a... |
Is there any substance that's a 0-0-0 on the NFPA diamond? Basically a perfectly safe chemical. |
Is there any substance that's a 0-0-0 on the NFPA diamond? |
I have been given pK values of a-amino group, a-carboxyl group and side chain of cysteine. How can I find the ionic charge on it at different pH values? |
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