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I've noticed that when adding lemon juice to carbonated water, large 'soapy' bubbles appear on the surface. Since I'm adding another acid to a solution of carbonic acid, I would maybe expect a faster release of CO2, but the bubbles I'm seeing do not resemble the usual fizzy drink bubbles. What's going on? |
Does citric acid react with carbonated water? |
I've read entire *Chapter 14: Organometallic Compounds* of Francis Carey's "Organic Chemistry" but I still didn't get an answer to my question.
Quote from the book:
>Because of their basicity *organolithium compounds* and *Grignard reagents* cannot be prepared or used in the presence of any material that bears ... |
I was thinking back to my chemistry major days and remembering the bunch of cool spectra we produced by various means (HNMR, IR, UV/Vis) and I remember all the cool 'self-interference' like couplets, triplets doublets, etc.
My question is basically motivated by the complexity of spectra, and the reductionist instin... |
Fourier transform for spectroscopy spectra? |
I've noticed that when adding lemon juice to carbonated water, large 'soapy' bubbles appear on the surface. Since I'm adding another acid to a solution of carbonic acid, I would maybe expect a faster release of $\ce{CO2}$, but the bubbles I'm seeing do not resemble the usual fizzy drink bubbles.
What's going on? |
Chemical energy is really nothing but electric potential energy.
The crucial difference is that chemical energy involves energy that can be extracted by breaking/making bonds.
For example, we say that the reaction $\ce{2H2 + O2->H2O}$ is accompanied by a release of energy. This energy is the difference of potenti... |
I would say that acids are better.
Why? Bases and acids dissolve flesh pretty easily (I'm thinking of $\ce{NaOH}$ and $\ce{HCl}$ here, weaker acids/bases -- not so much). Most of our body is made up of proteins, which are overall _pretty much_ neutral (generally). Both acids and bases can dissolve protein.
On the... |
What will be the product when 3,4-Dibromocyclohexene is reacted with sodium followed by heating with selenium? |
How to find whether there is oxygen present inside a well of diameter 1m at depth 50m ? Many people in Nepal are killed during cleaning wells because of lack of oxygen.. |
How to find whether there is oxygen present inside a well of diameter 1m at depth 50m? |
The ideal solution would be a single gas personal detector, such as [this one](http://catalog.enmet.com/compare/l-detector-for-co-h-sub-2-sub-s-o-sub-2-sub-or-l-2/l-detector-for-co-h-sub-2-sub-s-o-sub-2-sub-or-lel?forward=1&itemids=1002+1003+1004+1005+) (it's only the first example I found, I don't know this brand, but... |
I was thinking back to my chemistry major days and remembering the bunch of cool spectra we produced by various means (HNMR, IR, UV/Vis) and I remember all the cool 'self-interference' like couplets, triplets doublets, etc.
My question is basically motivated by the complexity of spectra, and the reductionist instin... |
How can one find whether or not there is oxygen present inside a well of diameter 1m at depth of 50m ?
Many people in Nepal are killed during cleaning wells because of lack of oxygen.. |
I would like to know how you synthesise glycosides of flavonoids and stilbenoids from the respective sugars and flavonoids/stilbenoids? |
How do you Synthesise Glycosides of flavonoids and stilbenoids? |
As per title, how would you go about synthesising amines from sugars? e.g. How would you synthesise the compound below from D-glucose?
![enter image description here][1]
[1]: https://i.stack.imgur.com/GySO2.png
Would glucose and ammonia work? |
How would you go about synthesising amines from sugars? |
First, the anwer is *“Would glucose and ammonia work?”* is: **no, definitely not**. The OH group is a poor leaving group, and alcohol + ammonia definitely won't yield an amine. Moreover, in your case, you have many hydroxyl groups and you only want one transformed into an amine, which is tricky.
I don't know how the... |
If it is possible, how would you estimate a substance's water solubility from data like its partition coefficient, $ \log P $, its dissociation constant, $pK_a $, its molar mass, etc.? |
Is it possible to estimate a substance's water solubility from data like the substance's partition coefficient, dissociation constants, etc.? |
The chemical structure of the compounds in question are:
![Hyperforin][1]
**Figure 1: Hyperforin**
![enter image description here][2]
**Figure 2: Tetrahydrohyperforin**
![enter image description here][3]
**Figure 3: Octahydrohyperforin**
[1]: https://i.stack.imgur.com/ZBy9N.png
[2]: https://i.... |
How would you synthesise tetrahydrohyperforin and octahydrohyperforin from hyperforin? |
How can one find whether or not there is enough oxygen for breathing present inside a (dry) well of diameter 1m at depth of 50m?
Many people in Nepal are killed during cleaning wells because of lack of oxygen.. |
How would you go about synthesising amino sugars from sugars? e.g. How would you synthesise the compound below from D-glucose?
![enter image description here][1]
[1]: https://i.stack.imgur.com/GySO2.png
Would adding ammonia (NH<sub>4</sub>) to it work? |
How would you go about Synthesising Amino Sugars from Sugars? |
If it is possible, how would you estimate a compound's water solubility from data like its partition coefficient, $ \log P $, its dissociation constant, $pK_a $, its molar mass, etc.? |
If I understand correctly, H<sub>2</sub> in the presence of Pd readily dissociates as it dissolves into the metal. With the dissociation energy for the H—H bond being so large, how is this possible?
At first I thought that the H atoms were falling to a lower energy level in the Pd that was somehow only available if... |
I'm tutoring few students for Chemistry. During the course, I many times use the phrase "Out of these possibilities this one is stable. So it is formed". I get questions like, "How do the molecules know?"
Honestly I don't know. How do the molecules know the future? How do they proceed to form "Most Stable" compound?... |
How do the molecules know the future? How do they proceed to form "Most Stable" compound? |
I'm new to Chemistry and in my textbook, it describes the Law of Definite Proportions and then goes on to describe the Law of Multiple Proportions.
The example they give is carbon monoxide and carbon dioxide, where the mass ratio of oxygen to carbon in carbon dioxide is 2.67:1 and the mass ratio of oxygen to carbon ... |
Law of Multiple Proportions: What is the significance of small whole numbers? |
I'm new to Chemistry and in my textbook, it describes the Law of Definite Proportions and then goes on to describe the Law of Multiple Proportions.
The example they give is carbon monoxide and carbon dioxide, where the mass ratio of oxygen to carbon in carbon dioxide is 2.67:1 and the mass ratio of oxygen to carbon ... |
I'm new to Chemistry and in my textbook, it describes the Law of Definite Proportions and then goes on to describe the Law of Multiple Proportions.
The example they give is carbon monoxide and carbon dioxide, where the mass ratio of oxygen to carbon in carbon dioxide is 2.67:1 and the mass ratio of oxygen to carbon ... |
I'm looking into building an absorption chiller as a decidedly non-professional DIY project. For safety reasons and because temps. > 0°C are sufficient, I won't be usiong ammonia but some saline solution as absorber and water as cooling agent.
The obvious choice for the salt would be LiBr, as this is used in comercial... |
What are alternatives to LiBr for use in absorption chillers? |
I'm looking into building an absorption chiller as a decidedly non-professional DIY project. For safety reasons and because temps. > 0°C are sufficient, I won't be using ammonia but some saline solution as absorber and water as cooling agent.
The obvious choice for the salt would be LiBr, as this is used in comercial ... |
What commonly availible salts are strong dessicants? |
When an electron absorbs energy and is in a higher energy orbit (I guess the atom would be in an unstable state), when the electron releases this energy, would all of this energy be released at the same time, or could it release energy one "level" at a time?
So for example if a Hydrogen atom absorbed a lot of energy... |
Does an "excited atom" lose energy gradually? |
Why is there a max radius for an orbit of an electron around a nucleus ?
I had a course in electromagnetism but I do not get this. |
Why is there a max radius for an orbit of an electron around a nucleus? |
What is needed to measure distance between two electrodes imersed in seawater ?
I have tried measuring the voltage across the path (a suposed resistance) with a constant current source (about 10uA) passing the water to GND of circuit. (the resistance is suposed proportional to distance of electrodes) The probes are... |
If I understand correctly, H<sub>2</sub> in the presence of Pd readily dissociates as it dissolves into the metal. With the dissociation energy for the H—H bond being so large, how is this possible?
At first I thought that the H atoms were falling to a lower energy level in the Pd that was somehow only available if... |
I just [read][1] that saturated palladium hydride, $\ce{PdH}$<sub>0.7</sub>, when exposed to oxygen will generate heat and water on it's surface, $\ce{4 H}$<sub>(Pd)</sub> $\ce{+O2}$<sub>(g)</sub> $\ce{\to 2 H2O}$<sub>(g, l)</sub>.
What is going on?
[1]: http://mattson.creighton.edu/H2-Uptake.pdf |
I'm guessing that when the $\ce{H}$ atoms leave the palladium are they still monatomic for an instant, but without the $\Delta H^0_f = 436 kJ/mol$ extra energy that free $\ce{H}$ atoms would normally have, as bypassed by the $\ce Pd$ somehow. Most of the $\ce{H}$ atoms simply fall in step with one another, reforming $... |
So I have been freezing ice a lot recently, and I will come out and say it, as it turns out it is, albeit unlikely, it is sometimes possible for ice to "explode." I was not so aware of this before, but from now on I consume my ice beverages with deliberate care.
The first action I have taken is to make sure no bubbl... |
How might one reduce the concentration of bubbles in their ice, from ice cube trays? |
(Further description would help. The following is a preliminary answer.)
There are several possible reasons for your unstable results:
Possibility 1: Wrong electrodes
-------------------------------------
Ag|AgCl pellets seem like an odd choice of electrodes for this application. What are the reasons for usi... |
What is needed to measure distance between two electrodes imersed in seawater ?
I have tried measuring the voltage across the path (a suposed resistance) with a constant current source (about 10uA) passing the water to GND of circuit. (the resistance is suposed proportional to distance of electrodes) The probes are... |
Have you looked into silica gel or zeolites? Both are non-toxic, and thus likely obtainable by private persons. Zeolites are used in self-refrigerating beer kegs. |
On our chemistry exam, a question asks "Which force is present between Fe particles? a) Van der Waals b) Metallic"
At first it seemed obvious that it was metallic; however, upon closer reading, it seemed like a trick question. First of all, there's no such thing as a metallic force. In addition, I'm not sure if Van ... |
Do metallic bonds contain London dispersion forces? |
Are there any simple at-home experiments to test the relative viscosity of alcohol to water?
If they are the same or practically the same, are there any household liquids that are less viscous than water? If so, how can I demonstrate this to first-graders? |
How to compare viscosity of alcohol to water? |
A common experiment would be to have two concentric cylinders. The outer one can rotate almost freely (with some slight and constant retardation/breaking applied), while the inner one is driven by a motor, [like so][1]. Between them is a layer of the liquid that you wish to determine the viscosity of. The speed of the ... |
I want to study what happen in a Internal combustion engine when mixing fossil fuel whit other chemicals, for ex:
Acetone drastically reduces the surface tension. Most fuel molecules are sluggish with respect to their natural frequency. Acetone has an inherent molecular vibration that "stirs up" the fuel molecules,... |
Any suggestions on diagramming the chemical structure for [cummingtonite][1]?
$$ (Mg,Fe)_7 Si_8 O_{22} (OH)_2 $$
As I understand it, the $(Mg,Fe)_7$ says the molecule has seven atoms that could be either Magnesium or Iron, with probably more Magnesium than Iron, meaning the structure isn't precisely defined, i.e. a ... |
Chemical diagram for cummingtonite? |
It says that the mass of Carbon and Hydrogen are 8:45. We are talking about an alkane here.
General formula is C<sub>n</sub>H<sub>2n+2</sub>. What is the particular formula? |
How to find the formula of this alkane? |
Crystalline structures of inorganic materials aren't usually represented by diagrams, but rather by 3D renderings. First, you need to find a crystallographic structure file, which are usually in CIF format. A Google search leads to [this one](http://www.crystallography.net/information_card.php?cif=9000141) for cummingt... |
(Initial, preliminary answer, here.)
There are several possible reasons for your unstable results:
Possibility 1: Wrong electrodes
-------------------------------------
Ag|AgCl pellets seem like an odd choice of electrodes for this application. What are the reasons for using them as electrodes? What is their... |
How do you add a benzene group to cyclic compounds like piperidine, piperazine and phenyl derivatives? |
How do you Benzylate (add a benzene group to) cyclic compounds? |
To my knowledge, metalic ions only precipitate from a solution as salts & and a process that could possibly produce monocristalline metal would be very interesting indutrially - I've never heard of one, so I don't think it is possible.
But: is it not conceivable to dissolve a metal in an acid (or maybe base), and th... |
Is it possible to crystallize a solid ingot of metal from an (acidic) aquaous solution? |
(How) Can you calculate the pH of a acetate buffer after adding 0,1mol of oxonium ions? |
I think you've just described the general concept of [Electrowinning?](http://en.wikipedia.org/wiki/Electrowinning)
There are a large number of ways to recover metals from solutions or molten salts.
Producing monocrystalline metals is a different matter - crystal grains in metals tend to be microscopic, but there... |
I want to study what happens in a internal combustion engine in which fossil fuels are mixed along with other chemical additives.
###Example:
Acetone drastically reduces surface tension.
Most fuel molecules are sluggish when it comes to their natural frequency. But acetone has inherent molecular vibration th... |
How do you add a benzene group to cyclic compounds like piperidine, piperazine and phenyl derivatives?
###Piperidine
![enter image description here][1]
###Piperazine
![enter image description here][2]
[1]: https://i.stack.imgur.com/GDXPC.png
[2]: https://i.stack.imgur.com/37jKD.png |
Formaldehyde has the formula CH<sub>2</sub>O, and the ratio of atoms in a simple carb is 1C:2H:1O. This fits the formula of formaldehyde. When I researched this, I found some sources saying that formaldehyde is the simplest carb, but other sources saying it is glycolaldehyde (C<sub>2</sub>H<sub>4</sub>O<sub>2</sub>). I... |
Is formaldehyde a carbohydrate? |
I'm tutoring few students for Chemistry. During the course, I many times use the phrase "Out of these possibilities this one is stable. So it is formed". I get questions like, "How do the molecules know?"
Honestly I don't know. How do the molecules know the future? How do they proceed to form "Most Stable" compound?... |
I was hoping there'd be someone who studies pesticides here.
Are they water soluble? Do they get absorbed in to the fruit? How well do you have to wash them? Etc.
Thanks in advance!
PS I had no idea how to tag this. |
Are pesticides used on fruit easily washed off? |
I'm not an expert. In simple words how do they differ `HHO` and `H2O` molecules? |
I was trying to isolate elemental bismuth from pepto bismal (bismuth subsalicylate) using the process seen [here](http://www.youtube.com/watch?v=Hp1fYtYEfoQ) but after I added the HCl, instead of getting a pink foamy substance I got a white liquid with some white foam. The only reason I can think of, for why this would... |
I was hoping there'd be someone who studies pesticides here.
- Are they water soluble?
- Do they get absorbed in to the fruit?
- How well would you have to wash the fruit to fully remove the residue?
|
I'm looking for more information on the composition of a <a href="http://www.rubbermaid.com/Category/Pages/ProductDetail.aspx?Prod_ID=RP091418">Rubbermaid Roughneck container.</a> The description says "Roughneck containers are made with a durable polyethylene material for a lifetime of durability and strength." Wikipe... |
What is the chemical composition of a Rubbermaid Roughneck container and is it feasible for me to make my own molds? |
For example how to write equation between methanoic acid and water.
How to find it? What is the methodology? How do H2O and methanoic acid change into general ion formulas with + and -? What's is the technique to find it?
I read the equation solved and i don't know how did the chemists do to find that H20+?=?... |
How to write an equation of an acid with water? |
I'm looking for more information on the composition of a <a href="http://www.rubbermaid.com/Category/Pages/ProductDetail.aspx?Prod_ID=RP091418">Rubbermaid Roughneck container.</a> The description says "Roughneck containers are made with a durable polyethylene material for a lifetime of durability and strength." <a hre... |
So, I have 1 litre of acetate buffer, and 0,1mol of oxonium ions/H3O+ is added. The task is to calculate the pH of this solution.
What I was thinking:
$$\ce{CH3COOH + H2O <=> CH3COO- + H3O+}$$
$$pH = pK_s + log\frac{c(\ce{Ac-})}{c(\ce{HAc})} = pK_s + log\frac{n(\ce{Ac-})}{n(\ce{HAc})}$$
$$pH = 4.74 + log\frac{n... |
I'm looking for more information on the composition of a <a href="http://www.rubbermaid.com/Category/Pages/ProductDetail.aspx?Prod_ID=RP091418">Rubbermaid Roughneck container.</a> The description says "Roughneck containers are made with a durable polyethylene material for a lifetime of durability and strength." <a hre... |
For example how can one write the equation between methanoic acid and water?
How does one find it? What is the methodology? How do $\ce{H2O}$ and methanoic acid change into general ion formulas with + and -? What's is the technique to find it?
I read the equation solved and I don't know what the chemists did to ... |
I'm looking for more information on the composition of a <a href="http://www.rubbermaid.com/Category/Pages/ProductDetail.aspx?Prod_ID=RP091418">Rubbermaid Roughneck container.</a> The description says "Roughneck containers are made with a durable polyethylene material for a lifetime of durability and strength." <a hre... |
Carbon with 5 bonds? |
Say you have two compounds with their own unique chemical structures and you know the environment (e.g. temperature, pressure, presence of enzymes) could you then, using this information, approximate the rate of reaction? And if so, how would you? |
Could you estimate the rate of reaction from the chemical structure of the reactants? If so, how? |
Say you have two compounds with their own unique chemical structures and you know the environment (e.g. temperature, pressure, presence of enzymes) could you then, using this information, approximate the rate of reaction? And if so, how would you? Please provide a mathematical answer, not just use some software. |
I'm going to use an example ; i could have used an other one ;
If understand with this equation i'll can understand others.
CH3COOH + H2O =CH3COO- + H3O+
what i know/understand:
this is the equation of methanoic acid with water
i understood why general formula of methanoic acid is CH3COOH
what i want to k... |
How to find products when you know reagents? |
I'm going to use an example (I could have used a differrent one)
If I understand with this equation I'll be able to understand others.
$\ce{CH3COOH + H2O ->CH3COO- + H3O+}$
Here is what I already understand:
- This is the equation of methanoic acid with water
- I understood why the general formula of methano... |
How can one find products when one knows the reagents? |
Is it possible to achieve an optical mirror coating to a flexible plastic part?
If vacuum metalization is possible, would the reflective coating layer be durable enough to withstand the bending of a flexible plastic such as polyurethane or a thermoplastic elastomer, without cracking over time?
Apologies if this i... |
Can flexible plastics have reflective coating (vacuum metalized)? |
Is it possible to achieve an optical mirror coating to a flexible plastic part?
If vacuum metalization is possible, would the reflective coating layer be durable enough to withstand the bending of a flexible plastic such as polyurethane or a thermoplastic elastomer, without cracking over time?
|
I'm going to use an example (I could have used a different one);
On the document it is about the study of the chemical balance of an acid-basic solution.
The chemists have written the chemical reaction equation to make a table of the evolution of pH during the reaction.
If I understand with this equation I'll b... |
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