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Generally, diketo compounds can react to form an enol-keto form and back again. This tautomery can **not** be considered a [1,3] proton shift due to orbital chemistry and has to be thought of as a combination of deprotonation/reprotonation or protonation/deprotonation steps — ask another question if you’re interested i... |
This is kind of like two questions but since they're related I have put them together.
Consider a monomer under a hopefully anatomically correct name 'Phenyl Carbolithia Divinylene Oxide [$\ce{C11H9LiO4}$] (For ease of understanding.)
![Skeletal Formula for molecule PCDO][1]![An image of the 3D structure][2]
W... |
For thing like 8× dilution, that would be like 1 ml of a solution and then 7 ml of something like water to dilute right? Would 50 ml solution and 50 ml water be a 2× dilution? I’m a bit unsure about the terminology. If I an OD of 0.123 from a sample diluted 5×, would multiply 0.123 by 5 to get the real OD? |
I have a couple of big barrels with a $50\,\mathrm{L}$ demi-water solution of the following nutrients:
$$
\begin{array}{rl}
200~\mathrm{\mu M} & \ce{NH4NO3} & +\\
30~\mathrm{\mu M} & \ce{KCl} & +\\
10~\mathrm{\mu M} & \ce{CaCl2} & +\\
10~\mathrm{\mu M} & \ce{KH2PO4} & +\\
\\
10~\mathrm{\mu M} & \ce{Fe-EDTA} &... |
I’ve attempted to solve this problem with percent composition, but it says the answer is wrong. Is it a $pV=nRT$ problem, and if so, can I use the units as they are given?
>A 0.02867 g sample of gas occupies 10.0 ml at 290.0 K and 1.10 atm. Upon further analysis, the compound is found to be 38.734 % $\ce{C}$ and 61.... |
Via percent composition, what is the molecular formula of the compound? |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
Relevance and Determination of the reflection symmetry +/- in Spectroscopy? |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
> May I manipulate the equation as though $T$ and $B$ were the kinds of symbols that we learned to manipulate in math class?
Yes, you can and *should* (that is, never leave out the units when you plug values into an equation: a quantity is always the product of a numerical value and a unit, and leaving out units is ... |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
So I just finished my final paper yesterday and I *tried* to attempt this **8 mark** question. I am not sure how to do it.
>$25\,\mathrm{ml}$ of $0.5\,\%~\mathrm{w/v}$ lactic acid ($\ce{C3H6O3}$, molecular mass $90.1\,\mathrm{g\,mol^{-1}}$, $\mathrm{p}K_{\mathrm{a}} = 3.86$ was neutralised by $13.1\,\mathrm{ml}$ of ... |
what kind of solvent would you use to remove an oil based stain?
I need help for a chemistry lab report and I tried to llok it up but nothings seems to be helping me |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
What kind of solvent would you use to remove an oil based stain?
I need help for a chemistry lab report and I tried to look it up but nothing seems to be helping me |
What solvents can get rid of oil stains? |
C, Rb, Ga, Ge
I am confused in the sense that i don't know what it means by released the smallest about of energy upo gaining? would it be Rb because the shell is so big that when it looses an electron the overall NRG doesn't really matter?
|
Which of the following releases the smallest amount of energy upon gaining an electron? |
$\ce{C}$, $\ce{Rb}$, $\ce{Ga}$, $\ce{Ge}$
I am confused in the sense that I don't know what it means by "released the smallest about of energy upon gaining?" would it be $\ce{Rb}$ because the shell is so big that when it loses an electron the overall energy doesn't really matter?
|
I know a little bit about unknown compounds but I am still new to the topic here. I know that you could use filtration, chromatography and distillation. You can also combine the unknown with others to form a compound. And you can measure properties and such and such to figure out what the compound is.
If I were to d... |
What are some general tests that would determine an unknown compound? |
If there are two electrons located in a shell (which contains two subshells) the molecule can either have a singlet state (if both electron are in the same subshell; because of the Pauli principle) or a triplett (if the two electrons are in the two different subshells).
The sign + or - means symmetric or antisymmetr... |
Alright this is similar to a question that I have answered before but I will just give you the reasoning for this phenomenon. I will **not** give you the answer since this appears to be a homework question.
**Why an atom gains energy when you take off an electron?**
Well for this, think of the attractions between t... |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect on other liquids inside the container? Is there a feasible scenario where the above can actually happen? |
Alright, this is similar to a question that I have answered before but I will just give you the reasoning for this phenomenon. I will **not** give you the answer since this appears to be a homework question.
**Why an atom gains energy when you take off an electron?**
Well for this, think of the attractions between ... |
This is kind of like two questions but since they're related I have put them together.
Consider a monomer under a hopefully anatomically correct name 'Phenyl Carbolithia Divinylene Oxide [$\ce{C11H9LiO4}$] (For ease of understanding.)
![Skeletal Formula for molecule PCDO][1]![An image of the 3D structure][2]
W... |
>Which of the following planar structures would be aromatic?
![molecules][1]
Could someone help me determining the aromaticity of the compounds?
My Attempt:
(i) Not an aromatic compound since it only has 4 pi electrons that does not satisfy Hückel's (4n+2) rule.
(ii) Not aromatic because it only has 4 p... |
I'm going to take a shot at this question from a different angle, aiming for a more objective analysis. For that, I wish to bring up several concepts. Bear with me!
First of all, what do we mean when asking if something is relevant or not to Chemistry? A precise and exact definition is not trivial, but let us consid... |
Is anything about the material known? And how much of it do you have?
If you think the material might be inorganic, an adsorption, emission, or mass spectroscopy might be the first step, as that will tell you what elements are in it. If the sample is large enough, and can be formed into crystals, then x-ray diffract... |
I am asked determine whether the following process is likely to involve a carbocation rearrangement or not.
![enter image description here][1]
I think it is possible through the rearrangement below (though the rearrangement cannot become a secondary or primary carbocation). Can someone please clarify if the carb... |
![three molecules][1]
The textbook states that a) has 2 gauche interactions, b) has 3 gauche interactions and c) has 3 interactions.
But how do we determine this? I thought a gauche interaction would occur when two methyl groups are side by side, however I'm unsure where these answers are coming from.
[1]: h... |
How were the absolute masses of atoms calculated before the mass spectrometers? |
> Suggest a synthetic route to amide C from the alkyl chloride B (reaction mechanisms are _not_ required). Standard reagents and solvents may also be used.
![molecules][1]
In this question immediate reaction is to make a grignard reagent with B by reacting it with magnesium and have it attack $\ce{COX(N(Me)2)}$ t... |
If I have three aqueous ionic solutions in which I know that the cation is $\ce{Al^3+}$, $\ce{Mg^2+}$, or $\ce{Zn^2+}$, and that how do I find out which is which?
I was thinking to add $\ce{OH-}$ in the form of $\ce{NaOH}$, or perhaps some other thing to produce a precipitate, and testing these precipitates in othe... |
Related to my previous question: http://chemistry.stackexchange.com/questions/31135/is-solubility-coefficient-affected-if-ion-data-is-given-in-ksp
> $200\,\mathrm{mL}$ solution of $0.02\,\mathrm{M}\,\ce{AgNO3}$ is added to $200\,\mathrm{mL}$ $\ce{CrO4^{2-}}$ and $\ce{PO4^3-}$ ions. Find out both of $Q_{\mathrm{sp}}... |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect (even on the position of the molecules in the container) on other liquids inside the container? Is there a feasible scenario where the above can actually happen? |
In our chemistry lab we performed the following experiment below.
> Given that $\mathrm{K_{sp}\:(\ce{AgCl}) = 8.2 \cdot 10^{-11}}$ and $\mathrm{K_{sp}\:(\ce{PbCl_{2}}) = 1.7 \cdot 10^{-5}}$
>Procedure:
0.2 mL each of $\mathrm{0.05\: M \: \ce{Ag+}}$ ions and $\mathrm{ 0.05\: M \: \ce{Pb^{2+}}}$ ions were added i... |
In our chemistry lab we performed the following experiment below.
> Given that $K_\mathrm{sp}(\ce{AgCl}) = 8.2 \times 10^{-11}$ and $K_{\mathrm{sp}}(\ce{PbCl_{2}}) = 1.7 \times 10^{-5}$
>Procedure:
$0.2\,\mathrm{mL}$ each of $\mathrm{0.05\: M \: \ce{Ag+}}$ ions and $\mathrm{ 0.05\: M \: \ce{Pb^{2+}}}$ ions were... |
The $K_\mathrm{D}$ (distribution coefficient) of coffee water at $25°\mathrm{C}$ is $7.8$ in a methylene chloride/water system. If there is $2.0\,\mathrm{g}$ of caffeine in $200\,\mathrm{mL}$ of water, calculate the grams and the % of caffeine that can be extracted with a single $100\,\mathrm{mL}$ portion of methylene ... |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect (even on the position of the molecules in the container) on other liquids inside the container? Is there a feasible scenario where the above can actually happen? I am interested in... |
This is snapshot from **LG Wade Organic Chemistry**.I have a doubt with a particular statement in the book.**It says that Grignard reagent does not displace halides as easily as acetylide ions do**.
*But should'nt it be the other way round. Acetylide ions having sp carbon is much more electronegative compared to sp3... |
Why do Grignard reagents or Organolithium compounds not displace halides as easily as acetylide ions do? |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect on other liquids inside the container? Is there a feasible scenario where the above can actually happen? I am interested in a scenario where the two liquids only separates themselv... |
I'm measuring buffer capacity by titrating $\ce{NaOH}$ into a buffer of $\ce {H_3PO_4}+{NaH_2PO_4}$. I'm measuring buffer capacity by recording the amount of $\ce{NaOH}$ required to increase the pH of the buffer by 2 units, and then taking the ratio.
My problem is that I have no idea how much $\ce{NaOH}$ I'll need ... |
I'm measuring buffer capacity by titrating $\ce{NaOH}$ into a buffer of $\ce {H_3PO_4 + NaH_2PO_4}$. I'm measuring buffer capacity by recording the amount of $\ce{NaOH}$ required to increase the pH of the buffer by 2 units, and then taking the ratio.
My problem is that I have no idea how much $\ce{NaOH}$ I'll need ... |
Dipole Moment Anomaly in Fluorine and Chlorine Compounds. What factors affect them? |
<h3>In case of metal deficient defects in the crystal lattice of a metal, the positive voids are filled by electrons. <p></h3>
- How does this result in the coloration of a substance?
- Does this condition arise only in the case of metals?
|
What is the dipole moment of the most stable conformer of 1,1,2,2-tetrafluoroethane? |
Is there a method to precipitate a solution of iron, nickel and silicon in any chemical form? My objective is to obtain a pure metallic powder, pure and/or alloyed in a controlled form, similar to powder obtained from an atomizing machine or from highly toxic carbonyl metallurgic processes.
|
I am under the impression that elements from the third period onwards can promote electrons into d orbitals to form hybridised orbitals. Why would an element in the third period promote an electron to the 3d orbital when we learn that 4s orbitals are filled first because they are lower in energy (is it to do with orbit... |
This is a snapshot from **LG Wade Organic Chemistry**. I have a doubt with a particular statement in the book. **It says that Grignard reagents do not displace halides as easily as acetylide ions do**.
*But shouldn’t it be the other way round. Acetylide ions having an sp-hybridised carbon are much more electronegati... |
This is a snapshot from LG Wade Organic Chemistry. I have a doubt with a particular statement in the book. It says that Grignard reagents do not displace halides as easily as acetylide ions do.
But shouldn’t it be the other way round? Acetylide ions, having an sp-hybridised carbon, are much more electronegative comp... |
I learnt that halogen always form covalent bond to becoms diatomic molecules. But why astatine is monoatomic? I mean they have the same properties, why can they all be diatomic? |
I am asked determine whether the following process is likely to involve a carbocation rearrangement or not.
![enter image description here][1]
I think it is possible through the rearrangement given above (though the rearrangement cannot become a secondary or primary carbocation). Can someone please clarify if th... |
I am asked determine whether the following process is likely to involve a carbocation rearrangement or not.
![impossible rearrangement][2]
I think it is possible through the rearrangement given above (though the rearrangement cannot become a secondary or primary carbocation). Can someone please clarify if the ca... |
Both metal powders can be preapred electrochemically.
Iron dust is prepared using solution containing $\ce{FeCl3}$ with addition of $\ce{AlCl3}$ to make the solution more conductive. The process occurs at elevated temperature 60°C. Unfortunately exact process parameters are hard to find. But following graph could h... |
I've recently read that Trinitrophenol (Picric Acid) is more explosive than TNT. (The Relative effectiveness factor of Picric acid is 1.20).
Personally, I think that the mesomeric effect of Oxygen's lone pairs in Picric Acid should keep the Nitro groups 'happy' (analogy wise), because of the increase of electron den... |
Why is Picric Acid more explosive than TNT? |
I would like to know if it is safe to mix organic solvents together or organic solvents with some compounds listed below.
In a mixture with random ratios (greater than zero) we have:
- Ethanol
- Methyl ethyl ketone
- Bitrex (aka Denatonium)
- Isopropanol
- n-butanol
- n-propanol
- Ethyl acetate
... |
![enter image description here][1]
[1]: https://i.stack.imgur.com/Flcnu.png
The graph of rotational heat capacity above shows a small maximum before approaching the equipartition value. What is the origin/physical explanation of this maximum? |
What is the origin of the maximum in rotational heat capacity? |
If you’re testing for whether it’s entirely made of lead, you can do it with a simple density calculation rather than anything chemical – an easy typical way to do this is to immerse it in a known volume of water and see how much volume the object adds, then divide the weight by that. Lead is the one of the heaviest co... |
I've recently read that trinitrophenol (picric acid - relative effectiveness factor $1.20$) is more explosive than trintitrotoluene (TNT - relative effectiveness factor $1.00$).
Personally, I think that the mesomeric effect of oxygen's lone pairs in picric acid should keep the nitro groups 'happy' (analogy wise), be... |
Why is picric acid more explosive than TNT? |
One key problem with astatine is that it's incredibly unstable. There are no known stable isotopes, and the longest-lived has a half-life of ~8 hours. So no one has been able to (yet) prepare enough to make real measurements. Thus, we don't know for sure whether solid At is diatomic (like the other halogens) or monatom... |
I learnt that halogen always form covalent bonds to becoms diatomic molecules. But why is astatine monoatomic?
I mean they have the same properties, why shouldn't they all be diatomic? |
Why is Astatine monoatomic? |
I've got 6 test-tubes with 0,5+0,5ml of 0,005%, 0,0025%, 0,00125%, 0,000625%, 0,0003125% and 0,0003125% starch and 4,2 pH phosphate buffer solution(2,4,8,16,32 and 32-fold dilution of 1% starch solution)
0,5 ml of beta-amylase was added to each test-tube, and heated(without 6th test-tube). Then the absorbance of each ... |
With higher period the d-electrons of the metal are less strong bonded and therefore oxidative addition is easier for $\ce{Ir(I)}$ as for $\ce{Rh(I)}$ and much easier as for $\ce{Co(I)}$.
For metal carbonyl hydride: electrons with higher periode (5d) are stronger bound to the nucleus, so pKa is increasing in this wa... |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect on other liquids inside the container? Is there a feasible scenario where the above can actually happen? I am interested in a scenario where the two liquids only separates themselv... |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect on other liquids inside the container? Is there a feasible scenario where the above can actually happen? I am interested in a scenario where the two liquids only separates themselv... |
Fresh ice cubes almost instantly and easily cling on to fabric and other such rough surfaces. <br/>
A few minutes later the effect almost disappears completely though.
- What is the cause of this adhesion?
- Why does the effect vanish after some time? |
Why is fresh ice sticky? |
I learnt that halogens always form covalent bonds to becoms diatomic molecules. So why is astatine monoatomic?
I mean they have the same properties, why shouldn't they all be diatomic? |
Graphene in it's pristine form, a single sheet of pure sp2 hybridized benzenes, is (relatively speaking) one of the least chemically reactive materials known because of several reasons: one, its enourmous size (we keep making larger and larger single "molecules", now thanks to [IBM up to 4 inches][1]!). Secondly, its p... |
**Note: The CCSD(T) computations are currently being performed. I will include this full set of data in a couple of days.**
Recall that a dipole moment can be explained relatively simply by a separation of two charges. The dipole moment, $\mu$, is dependent on two things: the magnitude of the charge ($q$) AND the ... |
Despite the ubiquitous usefulness of electronic configurations (of elements) in explaining their behavious I have not been able to find out exactly how the configurations are determined.
Is there any sure-fire technique to detect them (like x-ray diffraction for crystal structure) or is it based on guesswork, throu... |
How are electronic configurations determined experimentally? |
Both metal powders can be preapred electrochemically.
Iron dust is prepared using solution containing $\ce{FeCl3}$ with addition of $\ce{AlCl3}$ to make the solution more conductive. The process occurs at elevated temperature 60°C. Unfortunately exact process parameters are hard to find. But following graph could h... |
Consider a container that contains a mixture of many liquids. Can two of these liquids phase separate without having any significant effect on other liquids inside the container? Is there a feasible scenario where the above can actually happen? I am interested in a scenario where the two liquids only separates themselv... |
Flame tests are a common way of identifying trace amounts of alkali metals (and to a lesser extent alkaline earth metals) in mixtures. Certain salts of $\ce{Ba, Sr}$ are also used in fireworks for their ability to impart a colour to the flame.
Although predominant among s block elements this behaviour is also seen ... |
Why do s-block elements impart color to a flame? |
**Note: The CCSD(T)/haQZ computations are currently being performed. I will include this full set of data in a couple of days.**
Recall that a dipole moment can be explained relatively simply by a separation of two charges. The dipole moment, $\mu$, is dependent on two things: the magnitude of the charge ($q$) AND... |
For a solution such as:
Luria-Bertani (LB) Broth:
10 g tryptone
5 g yeast extract
10 g of NaCl ($M = 58.44\ \mathrm{g/mol}$)
q.s. to 1 l, pH to 7.2, autoclave.
I would like to make a bulk amount of premixed powder, i.e. combine 1 kg tryptone, 500 g yeast extract and 1 kg NaCl in a big bottle, shake it... |
In our chemistry lab we performed the following experiment below.
> Given that $K_\mathrm{sp}(\ce{AgCl}) = 8.2 \times 10^{-11}$ and $K_{\mathrm{sp}}(\ce{PbCl_{2}}) = 1.7 \times 10^{-5}$
>Procedure:
$0.2\,\mathrm{mL}$ each of $\mathrm{0.05\: M \: \ce{Ag+}}$ ions and $\mathrm{ 0.05\: M \: \ce{Pb^{2+}}}$ ions were... |
Fresh ice cubes almost instantly and easily cling on to fabric and other similarly rough surfaces.
A few minutes later, however, the effect almost completely disappears.
- What is the cause of this adhesion?
- Why does the effect vanish after some time? |
I’ve got six test-tubes with $0.5\ \mathrm{ml}+0.5\ \mathrm{ml}$ of 0.005 %, 0.0025 %, 0.00125 %, 0.000625 %, 0.0003125 % and 0.0003125 % starch and 4.2 pH phosphate buffer solution (2, 4, 8, 16, and 32-fold dilution of 1 % starch solution).
0.5 ml of beta-amylase was added to each test-tube, and heated (without sixth... |
Both metal powders can be preapred electrochemically.
Iron dust is prepared using solution containing $\ce{FeCl3}$ with addition of $\ce{AlCl3}$ to make the solution more conductive. The process occurs at elevated temperature 60°C. Unfortunately exact process parameters are hard to find. But following graph could h... |
First, let me tell you about the pitfalls of Lineweaver-Burke plots. The tranformations of your data (i.e. taking the reciprocal) distort the error structure of your data and can lead to erroneous fits. It is better to directly use nonlinear fitting techniques to find kinetic parameters. These techniques do not requ... |
Companies that sell such mixtures usually make them by dissolving everything into a solution, lyophilizing the solution, and then grinding the lyophilized residue. This guarantees that the size of particulates in the mixture will not be related to the chemical identity of the particulates.
If you have to mix powder... |
I've searched all over the net but couldn't find this anywhere.Can someone explain me how to calculate number of geometrical isomers in allenes like $CH_3-(CH=CH)_4-CH_3$ or $CH_3-(CH=CH)_5-CH_3$ ? Please help sort this out. |
How to calculate the number of geometrical isomers in allenes? |
I've searched all over the net but couldn't find this anywhere.Can someone explain me how to calculate number of geometrical isomers in allenes like $CH_3-(CH=CH)_4-CH_3$ or $CH_3-(CH=CH)_5-CH_3$ ? Please help sort this out. |
What is the meaning of reduction and oxidation in organic chemistry?
From what I learned in General chemistry - **OIL RIG** i.e oxidation is loss and reduction is gain (of electrons).But what do we say about their usage in organic chemistry? I have seen their usage a lot of times in the form of reducing agents and oxi... |
What is the mechanism of formation of Grignard's Reagent? I could not find anything in my book nor is there much on the Internet. [this page][1]
[1]: http://research.cm.utexas.edu/nbauld/grignard.htm
tells something which I am unable to understand. Why are the 2 electrons in the Mg separated? Shouldn't they be to... |
What is the meaning of reduction and oxidation in organic chemistry?
From what I learned in General chemistry - **OIL RIG** i.e oxidation is loss and reduction is gain (of electrons).But what do we say about their usage in organic chemistry? I have seen their usage a lot of times in the form of reducing agents and ox... |
What is the mechanism of formation of Grignard's Reagent? I could not find anything in my book nor is there much on the Internet. [this page][1]
[1]: http://research.cm.utexas.edu/nbauld/grignard.htm
tells something which I am unable to understand. Why are the 2 electrons in the Mg separated? Shouldn't they ... |
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