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Steriochemistry of pinacole pinacolon rearrangement

I just read an example of pinacole pinacolon rearrangement, in 1,2-methylhexane-1,2-diol. (Forgive me if the IUPAC name is wrong). From this I can see the migrating group is attacking from the back ...
-1
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1answer
39 views

Forces operating in molten ionic solids

What type of forces exist between ions in molten ionic solids? If this force is electrostatic attraction only, then how is it different from electrostatic interaction when ionic compound exist as ...
0
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0answers
8 views

Are (sponataneous) exothermic reactions spontaneous due to increase in stability of products or increase in the entropy of the surroundings?

The lattice formation of an ionic compound from its infinitely separated gaseous ions is spontaneous under standard conditions, but I cannot figure out the 'driving force' behind this. One way to look ...
2
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0answers
34 views

Why is nitrate anion substituted but bromide anion is not in Von Richter reaction?

In Von Richter reaction which is a nucleophilic aromatic substitution. As according to this source, there is only a 37 percent yield of the product.I want to know what are the competing side ...
6
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3answers
3k views

Why can the acidic strength between H2S and HCl be explained on the basis of electronegativity but H2S and H2O can't?

Consider simply aqueous solutions of $\ce{H2S}$ and $\ce{HCl}$ . It is pretty much known that $\ce{HCl}$ is stronger than $\ce{H2S}$ in water. The reason behind that first is the electronegativity of ...
2
votes
1answer
97 views

Ventilating combustion byproducts in water heaters

I'm designing a system that will heat water by burning natural gas which is commonly available. I would like to have a slow flame because water will need to reach $\mathrm{70^\circ C}$ and stay there. ...
0
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2answers
77 views

Kinetic energy of liquid

Does intermolecular force of attraction have anything to do with molecules having more energy in their liquid state than their solid state? If not, what is responsible for greater kinetic energy in ...
2
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0answers
19 views

Dominant factors rendering very low solubility of large aromatic molecules

In terms of structural basis, alkanes are insoluble or immiscible in water because of such presence of C–H...O interactions that are in regime of van der Waals interaction, which tends to be regarded ...
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0answers
11 views

What is the relation between distance from nucleus and shielding power?

In my chemistry textbook it is given as: "Comparing orbitals within the same shell, we say that the s orbital is more penetrating than the p or d orbitals, meaning that an electron in an s ...
0
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0answers
25 views

Can you develop algorithms to predict synthesis of peptides?

This may be a very foolish question, but do (complex) algorithms exist to predict the steps and materials involved (or therefore different options and paths) in synthesis for the given input of for ...
-1
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0answers
19 views

Proof of average spherical particle radius, with concentration, density, number of particles [closed]

During the semester, when studying light scattering, we 've been given an exercise: Prove, that the mean radius of spherical particles is given as: $r = \sqrt[3]{\frac{3cV}{4\pi\rho N}}$ where: $c$ ...
2
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1answer
50 views

dehydration of an alcohol (3-methyl-1-phenylbutan-2-ol)

I was thinking of dehydrating this alcohol: 3-methyl-1-phenylbutan-2-ol Its structure is: My concern is which of the following would it form: The problem is that the first one comes from a stable ...
1
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0answers
23 views

Heating effect on Orthoboric Acid

I am a high school student and was studying about the effects of heating orthoboric acid, and I saw two textbooks putting different statements. One book says, On heating above 370K, orthoboric acid ...
-3
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0answers
21 views

What will be the structure of the product with appropriate relative stereochemistry? [closed]

What will be the structure of the product with appropriate relative stereochemistry?
19
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3answers
8k views

Why are pi bonds only formed when sigma bonds are formed?

While studying about bonding there was one statement that "pi bonds can only be formed only with sigma bonds" as we know that in double bond there is 1 sigma bond and 1 pi bond but then one question ...
1
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1answer
71 views

Are all chiral carbons sp3 hybridised?

I had this doubt, whether all asymmetric chiral carbons must necessarily be $\mathrm{sp^3}$ hybridized. For sure, we know that double or triple bonded carbon atoms don't shows such chirality, but is ...
2
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2answers
2k views

Why Freundlich adsorption isotherms fails at high pressure conditions?

Experimentally it was determined that extent of gas adsorption varies directly with pressure, and then it directly varies with pressure raised to the power 1/n until saturation pressure Ps is reached. ...
1
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0answers
31 views

Is hydrogen peroxide a better oxidizing agent than chlorine gas?

If we compare the standard reduction potentials of $\ce{H_2O_2}$ with that of $\ce{Cl_2}$: $\ce{H_2O_2 + 2H^+ + 2e^- <=> 2H_2O : E^o = 1.78V}$ $\ce{Cl_2 + 2e^- <=> 2Cl^- : E^o = 1.36V}$ (...
9
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2answers
546 views

Determining if the product would be cis or trans after an anti elimination on fischer projections

I find these kind of problems really confusing for some reason, but I saw a way on the web and tried doing it that way: I considered the basic Fischer operations (Vertical: Below the plane of paper, ...
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0answers
19 views

Hybridisation of XeF4

Is hybridisation of orbitals of Xe in XeF4 sp3d2 or dsp2? Are the lone pairs present in hybrid orbitals? How to prove whether they are hybridised or not in the square planar geometry?
1
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1answer
55 views

Elimination reaction mechanism decision (order = 1 or 2)

Match the following: \begin{array}{} & \textbf{Column I}&&\textbf{Column II} \\ \text{(A)} & \ce{CH3-CHBr-CD3} \text{ on treatment with alc. KOH gives}& \text{(P)}& \text{E1 ...
4
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0answers
59 views

Hund's rule for comparing term symbol energies in excited state

This question was asked in an exam: The lowest energy electronic state for excited state carbon atom is, a. $^1D_2$ b. $^3D_1$ c. $^3D_3$ d. $^3D_2$ Although we have been taught Hund's rule for ...
1
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2answers
59 views

Why does CO2 diffuse out of a cylinder in the absence of a pressure difference?

Suppose I have a thermally insulated cylinder containing carbon dioxide (assuming it is ideal) at 1 atm pressure(atmospheric pressure is 1 atm). Now let's consider two cases: CASE-1: I cut open the ...
138
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7answers
45k views

Why doesn't water burn?

Hydrogen is flammable, and for any fire to burn it needs oxygen. Why does a compound made of hydrogen and oxygen put out fires instead of catalyzing them? I understand that hydrogen and water are ...
1
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1answer
43 views

Why doesn't the graph of radial part of wavefunction of 2p orbital change its sign? [closed]

Below I have given the graphs of radial part of the wave functions of $\mathrm{2s}$ and $\mathrm{2p}$ orbitals respectively. The graph of the $\mathrm{2s}$ orbital makes sense. It has a radial node ...
1
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1answer
26 views

How to dissolve brass surrounded by aluminium?

I have a broken off brass needle stuck in a caste aluminum hole. (It’s the pilot mixture jet on a carburetor). I was wondering if there was a chemical that would dissolve the brass while not reacting ...
1
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0answers
37 views

What happens to water and oxygen produced due to dissociation of nitric acid?

Nitric acid is yellow in colour due to the dissolution of nitrogen dioxide gas. The nitrogen dioxide is obtained due to thermal dissociation of a portion of nitric acid: $$\ce{4HNO3 -> 2H2O + 4NO2 +...
1
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1answer
74 views

Why doesn't pure water conduct when it dissociates? [closed]

Sorry if this is an obvious question. I am told water dissociates, one product of which is negatively charged hydroxyl ions. This makes sense, but then why doesn't pure water conduct electricity? ...
11
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1answer
196 views

Why does the graph of the electrical conductivity of sulfuric acid/water solutions have this knee in the ~85%-~92% range?

This answer to an earlier question regarding the electrical conductivity of sulfuric acid provides a graph showing the conductivity of sulfuric acid/water mixtures ranging from 0% to 100% sulfuric ...
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1answer
31 views

Can you add oxygen to water to make it stale to help soothe stomach problems [closed]

Can you add oxygen to water to make it stale and drink it to help soothe stomach problems?
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0answers
13 views

The issue of Molar Volume of elements and their compounds [closed]

Since Molar Volume / Avogadro Number gives the Molecular Volume, I wonder how come the volume of molecules (and atoms) can shrink so much when going from elements into compounds. Is there any current ...
-3
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0answers
34 views

Data Analysis Activity [closed]

Activity Background: Five patients (Aliza Aldred, Bob Barton, Conor Chavez, Dwayne Drake, and Emma Eriksen) were administered a drug called warfarin, which is known to slow the formation of blood ...
7
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1answer
144 views

Are all protein tetramers considered to be “dimers of dimers”?

Is every tetramer thought to be a dimer of dimers? Because even if every subunit is unique in structure, it could be a heterodimer of heterodimers? Or is the term "dimer of dimers" reserved ...
3
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0answers
21 views

Predict the density of states (DOS) diagram for rhenium oxide (ReO3) from the molecular orbital diagram

The structure of rhenium(VI) oxide, ReO3, is similar to that of perovskite. Each rhenium atom is surrounded by six oxygen atoms (octahedral environment): Experimentally, the density of states diagram ...
8
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3answers
5k views

Wade's rules for Zintl ions

How do you apply Wade's rules to Zintl polyhedral cluster anions ? For example, I believe $[\ce{Bi_3}]^{3-}$ is a triangle. My approach to justify would be: 5 electrons per each Bi atom 3 electrons ...
8
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1answer
98 views

Out of tropolone and tropone, which is more soluble in water?

According to me tropolone has intramolecular H-bonding, so extent of H-bonding with water will decrease and thus, will be less soluble. Tropone (Cyclohepta-2,4,6-trien-1-one): Tropolone (2-...
-3
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0answers
47 views

Why is manganese (IV) oxide insoluble in water and organic solvents such as chloroform? [closed]

I haven´t been able to find references to support why $\ce{MnO2}$ is insoluble in water and organic solvents. I am specifically interested in two solvents: water and chloroform.
13
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4answers
919 views

What is the physical significance of the universal gas constant R?

While studying work done in isothermal processes I was told that the universal gas constant $R$ is the work done by the gas per mole per kelvin. I am sure I am missing something basic but I didn't ...
1
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1answer
48 views

How is most probable radius in quantum mechanical model equal to Bohr's radius in hydrogen atom

Most probable radius in 1s orbital for hydrogen electron is $\pu{0.529E-10 m}$ which is Bohr radius. But energy of electron in hydrogen atom is proportional to mean radial distance in atom. In this ...
5
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0answers
138 views

Analysis of metal carbonyl bonding in Fe(CO)5 using molecular orbitals

I am really struggling with this question we have been set in class: Metal-carbonyl bonding: Conceptionally, one can build up $\ce{[Fe(CO)5]}$ from the $\ce{Fe(CO)4}$ fragment plus free $\ce{CO}$ in ...
12
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1answer
2k views

Mathematical relation between bond angle and fraction of s or p character

In Concise Inorganic Chemistry by J.D.Lee (Adapted by Sudarsan Guha, Fourth Edition), on page 75, under the topic "Effect of Electronegativity - When the surrounding atom is same with different ...
2
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1answer
33 views

pH meter mechanism - connecting potential differences

This question was asked here: pH probe bulb - what is happening within the glass? and How does a pH glass electrode work?. But, the mechanism remains unanswered. How does a potential difference ...
13
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1answer
21k views

How to rationalise the planar structre of I2Cl6?

$\ce{I2Cl6}$ is a dimer of $\ce{ICl3}$. $\ce{ICl3}$ is T-shaped, with $\ce{I}$ being $\mathrm{sp^3d}$ and having two lone pairs. I read in Inorganic Reaction Mechanisms by R. K. Sharma that $\ce{I2Cl6}...
1
vote
2answers
7k views

Transition from ground state to excited state

I don't understand how to correctly find the term symbol of an excited state. I know that the first two permitted transitions for the Ne atom are 16.8eV and 19.8eV and I want to find the electronic ...
11
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2answers
1k views

Why does gas particle velocity affect rate of effusion?

I understand why smaller particles have more velocity, but I don't understand what velocity has to do with the rate of effusion: My reasoning is thus: Pressure is the number of impacts of particles ...
6
votes
1answer
64 views

Analysing reaction with chair conformation of substituted cyclohexane

Why doesn't Iodine liberate in the following reaction? (A) Inadequate ring size (B) Two Bromines are in equatorial positions (C) Steric hindrance of t-butyl group towards attacking $\ce{I-}$ ...
1
vote
1answer
2k views

Finding equilibrium temperature when two things are mixed

10 g of ice at −10 °C is added to 10 g of water at 85 °C. What is the final temperature and amount of ice left in the system? (System is kept inside an ideal insulator) This question may seem quite ...
10
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2answers
5k views

What is the difference between chemical equilibrium and dynamic equilibrium?

Is chemical equilibrium and dynamic equilibrium the same thing? Both point to the reversible reactions and no net changes in the concentrations of product and reactant. Dynamic equilibrium from ...
6
votes
1answer
17k views

HPLC: peak area vs concentration

Many text books say that there is a proportionality between the peak area of the chromatogram and the concentration. However, in my opinion, there should be a proportionality between the concentration ...
7
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3answers
2k views

Find the pH of an amphiprotic salt dissolved in water at room temperature

Let's say I have a polyprotic acid $\ce{H2A}$ with the following properties: $$ \begin{align} \ce{H2A &<=> HA- + H+} & K_1 &= 1\cdot 10^{-1}\\ \ce{HA- &<=> A^2-+ H+} & ...

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