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Which of the following compounds has the highest and the least dipole moments and why? |
We know when lithium is burnt in air, it forms lithium nitride and lithium oxide. I am wondering if this applies to aluminium (other metals) also? |
When aluminium is ignited in atmosphere, will it form only aluminium oxide or also aluminium nitride? |
According to this [paper][1], it is indeed formed when burning aluminium, but you could have predicted this simply by considering the standard enthalpy of formation of aluminium oxide ($\ce{Al2O3}$ = −1675.7 kJ/mol) which will be liberated upon ignition and this energy helps in breaking the strong nitrogen-nitrogen tri... |
[![The Question][1]][1]
[1]: https://i.stack.imgur.com/ktvFH.png
Question: Which of the following compounds will show highest dipole moment and why?
I figured out that, (4)th compound is very symmetric - so net dipole moment on the compound must be null.
How should I go about finding the compound with t... |
The previous answers are good ones. I just want to add a (longwinded) metaphorical picture to help understanding the freezing of water at -20C.
Imagine a tower of bricks (2 x 4 x 8 inches each) about 20 high. It is metastable, but the tiniest push will topple it because gravity pulls each brick to the lowest level.... |
I just started selfstudy with an organic chemistry textbook and I'm not quite getting the motivation behind the octet rule.
Per Bruice's textbook, the octet rule reads
> an atom is most
stable if its outer shell is either filled or contains eight electrons and it has no electrons
of higher energy
Why are atom... |
I'm currently working on an electrolytic setting where a stainless steel (430 series, mainly made of iron and chromium, but no nickel) anode is dissolved in acidic environment (sulfuric and phosphoric acids at moderate concentrations).
My concern is the hypothetical creation of dichromate ions, since they are carcin... |
I am attempting to interpret an experimental section on a scientific paper. The paper calls for 0.51 mmol of 3,5-dimethoxy phenol, 1.0 mmol of 3-methyl-3-butenal, 5 mol% of phenylboronic acid, 20 mol% of benzoic acid, and 2.5 mL of heptane. I am trying to figure out what is meant by mole% in this case. There are many d... |
What is Meant by Mole Percent? |
I just started selfstudy with an organic chemistry textbook and I'm not quite getting the motivation behind the octet rule.
Per Bruice's textbook, the octet rule reads
> an atom is most
stable if its outer shell is either filled or contains eight electrons and it has no electrons
of higher energy
Why are atom... |
I just started selfstudy with an organic chemistry textbook and I'm not quite getting the motivation behind the octet rule.
Per Bruice's textbook, the octet rule reads
> an atom is most
stable if its outer shell is either filled or contains eight electrons and it has no electrons
of higher energy
Why are atom... |
I have recently been reading a paper, in which given dihedral angles of alanine dipeptide molecule $\psi$ and $\phi$, the conformation is catagorized as either $\beta$-1, $\beta$-2, or $\alpha$. I was trying to see if it is possible to extend the same idea to QM9 molecules and cluster them into different groups based o... |
I am reading the experimental section of a paper, and it states
> [compound of interest] Isolated as a pale yellow oil after flash chromatography on silica gel, eluting with 1-2% EtOAc/pentane...
This is all this paper states in regards to the work-up procedure. I fully understand everything in this section exc... |
What is Meant by "Eluting with 1-2% EtOAc/pentane" in Terms of Flash Chromatography? |
When a double displacement reaction occurs with compound AB and CD, what determines that B and C are going to bond instead of A and C? |
How does a double displacement reaction work? |
Could anyone suggest a good application or a software that helps visualise molecular structures in 3d?
I have tried a few applications like King Draw and molecular constructor but I want to know if there are better ones out there. |
Here is a possibly interesting path to try for a Zinc (or Aluminum) amalgam, which can be used in organic synthesis (e.g., for the Clemmensen reduction) courtesy of the field of hydrometallurgy. It starts by first placing a sheet of, say, pure Zinc in HCl to create some surface absorbed H atoms (or Al in NaOH). Remove ... |
Here is a possibly interesting path to try for a Zinc (or Aluminum) amalgam, which can be used in organic synthesis (e.g., for the Clemmensen reduction) courtesy of the field of hydrometallurgy. It starts by first placing a sheet of, say, pure Zinc in HCl to create some surface absorbed H atoms (or Al in NaOH). Remove ... |
What are some software packages that allow visualization of molecules in 3D? |
According to this [paper][1], it is indeed formed when burning aluminium, but you could have predicted this simply by considering the standard enthalpy of formation of aluminium oxide ($\ce{Al2O3}$ = −1675.7 kJ/mol) which will be liberated upon ignition and this energy helps in breaking the strong nitrogen-nitrogen tri... |
How does the the nitrogen of thiazole in thiamine acquire a positive charge without being stabilized by another negative charge or by being a salt of an anion?
[1]: https://chemistry.stackexchange.com/questions/125628/a-question-about-nicotinamide-adenine-dinucleotide |
On our exams we are asked to determine which synthesis method is best suited for a given compound. We have discussed direct synthesis methods such as high temp. and ampull, and indirect synthesis methods such as solvothermal, sol-gel and ion exchange.
I thought that the direct high temperature synthesis was mostly... |
Here is a possibly interesting path to try for a Zinc (or Aluminum) amalgam, which can be used in organic synthesis (e.g., for the Clemmensen reduction) courtesy of the field of Hydrometallurgy. It starts by first placing a sheet of, say, pure Zinc in HCl to create some surface absorbed H atoms (or Al in NaOH). Remove ... |
Here is a possibly interesting safe path to try for a Zinc (or Aluminum) amalgam, which can be used in organic synthesis (e.g., for the Clemmensen reduction) courtesy of the field of Hydrometallurgy. It starts by first placing a sheet of, say, pure Zinc in HCl to create some surface absorbed H atoms (or Al in NaOH). Re... |
Here is a possibly interesting safe path to try for a Zinc (or Aluminum) Hg amalgam, which can be used in organic synthesis (e.g., for the Clemmensen reduction) courtesy of the field of Hydrometallurgy. It starts by first placing a sheet of, say, pure Zinc in HCl to create some surface absorbed H atoms (or Al in NaOH).... |
In my textbook it is written that Mg(OH)2 is slightly soluble in water and it forms a milky solution which is called "Milk of Magnesia". It's solubility can be increased by the addition of NH4Cl. But how? There is no reason. |
How NH4Cl increases the solubility of Mg(OH)2 in water? |
Here is a possibly interesting safe path to try for a Zinc (or Aluminum) Hg amalgam, which can be used in organic synthesis (e.g., for the Clemmensen reduction) courtesy of the field of Hydrometallurgy. It starts by first placing a sheet of, say, pure Zinc in HCl to create some surface absorbed H atoms (or Al in NaOH, ... |
[![enter image description here][1]][1]Halogenation: how does the reaction go considering the methyl group?
[1]: https://i.stack.imgur.com/RSSgj.jpg |
Halogenation: how does the reaction go considering the methyl group? |
[![enter image description here][1]][1] My problem is wih the methyl group if it wasn't there i had no problem.
when the halonium bridge is made dose the methyl group shift to give a more stable transition state or not ?
[1]: https://i.stack.imgur.com/RSSgj.jpg |
[![Bromination of 4‐methylcyclohex‐1‐ene][1]][1]
My problem is with the methyl group. If it wasn't there, I had no problem.
When the halonium bridge is made does the methyl group shift to give a more stable transition state or not?
[1]: https://i.stack.imgur.com/tuFsZ.png |
In my textbook it is written that $\ce{Mg(OH)2}$ is slightly soluble in water, and it forms a milky solution which is called "milk of magnesia".
Its solubility can be increased by the addition of $\ce{NH4Cl}.$ But how? There seems to be no reason. |
How does ammonium chloride increase the solubility of magnesium(II) hydroxide in water? |
It might be obvious that entropy related to reactions always increases and i understand (somewhat) why this happens.My question is why if you have two hydrogen atoms in a vacuum without being bonded to a molecule they would form a bond.Does that not show a movement from chaos to order and thus a decrease in entropy? |
It might be obvious that entropy related to reactions always increases and I understand (somewhat) why this happens. My question is why if you have two hydrogen atoms in a vacuum without being bonded to a molecule they would form a bond. Does that not show a movement from chaos to order and thus a decrease in entropy? |
On our exams we are asked to determine which synthesis method is best suited for a given compound. We have discussed direct synthesis methods such as high temp. and ampull, and indirect synthesis methods such as solvothermal, sol-gel, and ion exchange.
I thought that the direct high temperature synthesis was mostl... |
How would I synthesize ethyl 2‐oxocyclohexane‐1‐carboxylate from cyclohexanone? |
After doing some reading, it is common to read that aluminum is corroded by oxygen, but that the thin layer of aluminum oxide protects the internal metal from further damage. How much does this layer of aluminum oxide protect the underlying layers? Does it completely seal off the aluminum or is there still a slow degra... |
Will aluminum continue to corrode after its surface is oxidized? |
The standard conditions for this transformation is NaH/KH in THF at reflux with diethyl carbonate (EtOCOOEt) with an acetic acid workup.
The Organic Syntheses procedure [here][1] uses dimethyl carbonate, but will be equally applicable for diethyl carbonate.
[1]: http://www.orgsyn.org/demo.aspx?prep=CV7P0351 |
As you will see if you look at the reference mentioned by @Mathew-Mahindaratne, the standard conditions for this transformation is NaH/KH in THF at reflux with diethyl carbonate (EtOCOOEt) with an acetic acid workup.
The Organic Syntheses procedure [here][1] uses dimethyl carbonate, but will be equally applicable ... |
I am a bit stuck on a basic chemistry concept. I understand that the Avogadro number indicates the number of chemical entities it has (ion, molecule or atom) What I don't understand is that when you add the masses of all of the elements in a compound, that it will equal to 6.022x10 atoms of that substance - why wouldn'... |
Why are moles of compounds have only 6.022x10 23 atoms? |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/TtKB8.png
I understand that the partially filled Ni intersects the Fermi level as there is a change from filled to unfilled orbitals. But what is the explanation for the lower binding energy of the filled 3d Cu orbital. Surely there would ... |
In UV photoelectron spectroscopy why are filled orbitals seen at a higher binding energy? |
I'm confused exactly on how to use the concept of solubility to get the amount of separation from a certain solute in the solution.
This arises from attempting to solve a problem regarding this matter. The problem described is as follows:
> $400$ grams of anhydrous sodium sulphate ($Na_{2}SO_{4}$) is dissolved
>... |
Can the solubility of a compound be used to estimate the degree of separation of a solute from a solution? |
Are ionic bonds stronger than covalent bonds?
I googled it and found various answers, some saying it is stronger and some saying it’s not.
|
Which bond is stronger? |
Adiabatic compression of an ideal monatomic gas. What would the change in entropy be? |
Is there any reaction available to convert cycling compounds to their corresponding aliphatic compounds?
eg. Converting cyclohexane to n hexane |
Is there any reaction available to convert cyclic compounds to their corresponding aliphatic compounds?
eg. Converting cyclohexane to n hexane |
Do
-Activators
-Competitive Inhibitors
-Non-Competitive Inhibitors
-Uncompetitive Inhibitors
all change the conformation of the targeted enzyme from T to R (activator), and from R to T (the rest) respectively?
Also, why does the Km of a reaction decrease with an uncompetitive inhibitor, while remainin... |
In an experiment, I have 2 endothermic reactions which are taking place simultaneously: A+B--C and E+G---Z, C and Z also take place in a reaction to form the final product of the process J. In my experiment, I have to use a single heating source, change the concentration of the chemicals in A+B and E+G such that the pr... |
Τhe electrons in the antibonding MO are the unpaired electrons of the molecule? E.g. $\ce{O2}$, by writing down the diagram for the MO we notice that there are only 2 electrons in the top antibonding orbitals thus 2 unpaired electrons, yet by writing down the Lewis structure, the molecule turns out to have 0 unpaired e... |
In an experiment, I have 2 endothermic reactions which are taking place simultaneously: A+B--C+D and E+G---Z+F, C and Z also take place in a reaction to form the final product of the process J. In my experiment, I have to use a single heating source, change the concentration of the chemicals in A+B and E+G such that th... |
In an experiment, I have 2 endothermic reactions which are taking place simultaneously: A+B--C+D and E+G---Z+F, C and Z also take place in a reaction to form the final product of the process J. In my experiment, I have to use a single heating source, and cannot change the concentration of the chemicals in A+B and E+G s... |
In an experiment, I have 2 endothermic reactions which are taking place simultaneously: A+B--C+D and E+G---Z+F, C and Z also take place in a reaction to form the final product of the process J. In my experiment, I have to use a single heating source, and cannot change the concentration of the chemicals in A+B and E+G s... |
From the table below, **it is evident that $\ce{AlCl_3}$ has a higher lattice energy than $\ce{AlF_3}$, even though $\ce{F}$ is smaller than $\ce{Cl}$. Why is this so?**
However, the melting point of $\ce{AlF_3}$ ($1291^\text{o} \text{C}$) is larger than that of $\ce{AlCl_3}$ ($192.4^\text{o} \text{C}$). I think the... |
Why does aluminum chloride have a higher lattice energy than aluminum fluoride? |
I know that the internet is full of enzyme and protein simulators which can show active site and 3D structure (like bioblender), but the problem with these programs is that they use predefined information and coordinates supplied by several databases (such as PDB ) , but actually I didn't find a software that can predi... |
**No. Aluminium stops corroding once a strong oxide layer is formed.**
Aluminium is a fairly reactive metal. The reason why it usually survives in air and water under normal conditions is because the aluminium oxide layer on the surface is very strong and normally protects the metal from further attack. Even if the ... |
How does ammonium chloride increase the solubility of magnesium hydroxide in water? |
Is a totally eclipsed Newman projection the most stable conformation for a 2 carbon compound, with one carbon bonded to more electronegative atoms (making them partially negative), and the other carbon with something less electronegative (making it partially positive)?
For example, let's imagine $\ce{CF3CH3}$. If th... |
From the table below (source: McMurry's *Chemistry* \[1, p. 212\]), it is evident that $\ce{AlCl_3}$ has a higher lattice energy than $\ce{AlF3},$ even though $\ce{F}$ is smaller than $\ce{Cl}$. Why is this so?
[![Table 6.3 Lattice Energies of Some Ionic Solids (kJ/mol)][1]][1]
However, the melting point of $\ce{... |
If you run a direct current, using pure Nickel electrodes, through a solution of NaOH and distilled water, you will separate the water into Hydrogen and Oxygen.
My question is, are there any other reactions that could possibly take place that would release anything other than Hydrogen and Oxygen? |
If
Temprature is directly proportional to volume (Charles's Law)
And
Temperature is directly proportional to pressure (Gay Lussac's Law)
Then why is pressure and volume inversily proportional?
|
Why is volume inversily proportional to pressure? |
If temprature is directly proportional to volume (Charles's law) and
temperature is directly proportional to pressure (Gay-Lussac's law), then why is pressure and volume are inversely proportional?
|
If you run a direct current using pure nickel electrodes through a solution of NaOH in distilled water, you will separate the water into hydrogen and oxygen.
Are there any other reactions that could possibly take place that would release anything other than hydrogen and oxygen? |
I get that oxygen is the terminal electron acceptor in oxidative phosphorylation. But why is it essential to accept these electrons and remove them as H2O? Oxygen is essential for cellular respiration, but after learning about cellular respiration it seems oddly unimportant. Why is having an efficient garbage collec... |
I get that oxygen is the terminal electron acceptor in oxidative phosphorylation. But why is it essential to accept these electrons and remove them as $\ce{H2O}?$
Oxygen is essential for cellular respiration, but after learning about cellular respiration it seems oddly unimportant. Why is having an efficient garba... |
Why is it important to remove the used up electrons in oxidative phosphorylation? |
Why is volume inversely proportional to pressure? |
Why oxidation potential of an electrode equals negative reduction potential of the same electrode? |
If temprature is directly proportional to volume (Charles's law) and
temperature is directly proportional to pressure (Gay-Lussac's law), then why is pressure and volume are inversely proportional?
(This question is not worth answering, thanks.
-kartikeya chauhan)
|
If temprature is directly proportional to volume (Charles's law) and
temperature is directly proportional to pressure (Gay-Lussac's law), then why is pressure and volume are inversely proportional?
|
I'm given the following information
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/3qszc.png
I'm then asked to determine the charge of the substrate Angiotensin 1 at the pH-optimum. I have found the pH-optimum to be 6.9.
How do I go about answering this question only knowing the o... |
Given the pH optimum of Angiotensin 1, how do I determine its charge? |
How to calculate molar mass of (6)UO2+2D and (6)UO2OH+D? |
I know that the internet is full of enzyme and protein simulators which can show active site and 3D structure (like bioblender), but the problem with these programs is that they use predefined information and coordinates supplied by several databases (such as PDB ) , but actually I didn't find a software that can predi... |
Is there a software that can predict the shape of a custom protein, given its amino acid sequence? |
There exist **two methods** for teaching electrochemistry, and of course two schools of teachers. The two methods are equivalent, but they are exactly the opposite of one another. I will take an example to explain it correctly : Let us speak of the Daniell cell Zn/Cu, which uses reduction potentials equal to -$0.76 $ V... |
There exist **two methods** for teaching electrochemistry, and of course two schools of teachers. The two methods are equivalent, but they are exactly the opposite of one another. I will take an example to explain it correctly : Let us speak of the Daniell cell Zn/Cu, which uses reduction potentials equal to -$0.76 $ V... |
Wikipedia has the following reaction:
> $\ce{Mg2Si + 4 HCl → 2 MgCl2 + SiH4}$
This seems to be a double displacement (metathesis) reaction, where $\ce{Si}$ has oxidation state $-4$. However, I thought that silane had silicon in the $+4$ oxidation state? For example, in this reaction:
$\ce{3 SiO2 + 6 H2 + 4 Al ... |
I have seen various discussions about the triple point of Gallium determined to a very precise value, so precise that it is used as a reference for NIST scales and measurements.
However, these reference related documents mean 'temperature' only when talking about triple point. Triple-point is classified as a (temper... |
What is the triple point pressure for Gallium? |
I have seen various discussions about the triple point of Gallium determined to a very precise value, so precise that it is used as a reference for NIST scales and measurements.
However, these reference related documents mean 'temperature' only when talking about triple point. Triple-point is defined as a (temperatu... |
I have use two aluminum pieces as electrodes to electrolys salt (NaCl) water. After the experiment, I found that wherever electricity flows, the electrode will be covered in some blackish substances. One electrode has more dark substances than the other
[![enter image description here][1]][1]
[1]: https://i... |
The following is mentioned in NCERT (government textbook in India used in all schools) under chemical properties of $\ce{H2O2}:$
> (iv) Reducing action in basic medium
> $$\ce{I2 + H2O2 + 2 OH- -> 2 I- + 2 H2O + O2}$$
I feel the reaction is not correct. Since $\ce{H2O2}$ is a moderate/strong oxidizing agent, I... |
How can iodine oxidise hydrogen peroxide? |
the oxidation state of oxygen in Eo2 and Eo3 is +4 and +6 respectively ...then how can both of them be acidic ? |
why is both types of oxides (Eo2 and Eo) of group 16 acidic? |
I'm trying to find an answer as to how lowering the pH of the CuSO4 solution during electroplating of copper affects the amount of copper deposited onto the cathode.
My very basic understanding is that if the concentration of hydrogen is too high, then there is greater competition and hydrogen will be reduced instea... |
I am curious to know the mechanism of each reaction. Organic chemistry is satisfying for me because there is a mechanism behind each reaction which make a sense but when I Google for the mechanism of inorganic reaction I do not find any good results. That troubles me on thinking "Chemistry is really 100% Hypothetical".... |
Is organic chemistry mechanisms limited to organic chemistry? |
I am curious to know the mechanism of each reaction. Organic chemistry is satisfying for me because there is a mechanism behind each reaction which make a sense but when I Google for the mechanism of inorganic reaction I do not find any good results. I applied an organic reaction mechanism on an inorganic reaction and ... |
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