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2
votes
1answer
47 views

Friedel–Crafts acylation of substituted anisole

I am attempting to form a synthetic route to a tetrasubstituted benzene compound. In the scheme, there is a step that requires the formation of a carbon–carbon bond in the C-6 position of a methoxy ...
0
votes
0answers
24 views

How do we draw the Lewis structures of complex molecules and ions?

How do we draw the Lewis structures of complex molecules and ions such as ClOF3, OSF4-, F2SeO2, etcetera? I know that for simpler molecules, we can determine the central atom using lowest ...
-3
votes
0answers
13 views

Enthalpy change in an isothermal process at constant pressure [closed]

While studying thermodynamics I encountered a statement stating that " The Enthalpy change in an isothermal process is zero".I started analysing and got stuck when I came to the condition ...
0
votes
0answers
35 views

How do chiral molecules actually rotate light? [duplicate]

How do molecules actually change the direction of a photon of light? It requires more of a particle physics answer but the question is highly relevant for chemistry.
1
vote
0answers
10 views

How to extract transition density cube from .fch file in Gaussian? [migrated]

I have been trying to extract the transition density cube of a simple molecule, $H_2O$. I did a regular geometry optimization and then TD-DFT calculation with a keyword Density=Transition=1, which is ...
-1
votes
1answer
14 views

Why do we use external pressure to calculate work done by a gas in case of compression instead of using internal pressure?

According to formula work done is (Resisting pressure X dV)? Then in case of compression, isn't the resisting force is internal Pressure? Then why we the formula for compression is same as expansion ...
-2
votes
0answers
43 views

How to produce light of wavelength range 95nm to 100nm on large scale and if there is one in market then please send the link [closed]

i need light of wavelength ranging between 95nm to 100nm to perform an experiment on selective ionization of gas mixture and for this technique to be used at large scale i want to know about how to ...
1
vote
1answer
31 views

Relation between standard silver-silver chloride electrode potential and solubility product of silver chloride

I learned that $E^\circ_\ce{Cl^-|Ag,AgCl}, E^\circ_\ce{Ag^+|Ag}$ and $K_\mathrm{sp}$ of $\ce{AgCl}$ are related as $$\boxed{E^\circ_\ce{Cl^-|Ag,AgCl} = E^\circ_\ce{Ag^+|Ag} + \frac{RT}{F}\ln K_\mathrm{...
2
votes
0answers
25 views

Different products with varying aluminium chloride concentration in a reaction of propiophenone

How does the product change with varying $\ce{AlCl3}$ concentration? Answer: In excess, meta bromination is observed and if not, then alpha hydrogen is substituted by ketone halogenation mechanism I ...
1
vote
0answers
29 views

Confusion in D/L nomenclature

With regard to carbohydrates, it is known that in a Fischer projection, if the $-OH$ group is on the right side of the lowest priority asymmetrical (chiral) carbon, then we name it as D and if it is ...
5
votes
1answer
387 views

How much CO2 is produced when burning 1GJ of Natural Gas

Background I am trying to determine how many kg of $\ce{CO2}$ are released when burning 1 GJ of natural gas. What I've tried I have very little chemistry knowledge, but google led me to these two ...
3
votes
2answers
849 views

Which is a more accurate scale for a chemistry high school lab - a triple beam balance or a digital balance and why?

I would like to ask the experts of this chemistry community their opinions on which balance is more accurate and effective to use in a high school chemistry lab- a triple beam balance or a digital ...
7
votes
3answers
171 views

Choosing reaction stoichiometry in organic synthesis

Reading papers about organic synthesis, I see many cases like setting one material as 1.2 eq. I presume that reagents used more than 1 equiv are relatively inexpensive or less reactive than other ...
-1
votes
0answers
30 views

What container can i use to safely store isopropanol at 99.8%?

I finally get Isopropanol at 99.8% for cleaning purposes of electronics and plastics and my idea is to have various bottles, some with only Isopropanol and other mixed with distilled water What can i ...
-1
votes
0answers
29 views

The oxygen in hydronium has a pair of non-bonding electrons in its valence orbital. Would it be possible to bind one more proton (H+) to hydronium? [duplicate]

Hydronium oxygen has a pair of non-bonding electrons in its valence orbital. Chemically it would be possible to bind one more proton ($\ce{H+}$) to the hydronium and thus form the $\ce{H4O_x}$ cation....
-1
votes
0answers
11 views

What's the difference between Heat of Formation and Bond Enthalpies? [closed]

I don't quite understand the concepts of Heat of Formation and Bond Enthalpies, and why their respective formulas work, it would be really great if someone could please help explain the difference/...
-4
votes
0answers
19 views

How many electrons and protons are there in the sum of the hydronium atoms? (Homework) [closed]

Hydronium H₃O+ Hydrogen*3 3 Protons 3 Eletrons Oxygen 8 Protons 8 Eletrons -1 = 7 7+3= 10 Eletrons 8+3= 11 Protons Is correct ?
-4
votes
0answers
20 views

why BF3OEt2 use is additive with TIPSOTf or TBSOTf [closed]

why BF3OEt2 use is additive with TIPSOTf or TBSOTf in aldol type acetal addition reaction
-4
votes
0answers
23 views

Do the covalent bonds in water molecules promote hydrogen bonding between water and other molecules?

I think the question title is pretty self-explanatory but I was wondering if the covalent bonds in water promote hydrogen bonding between water and other molecules and whether they promote polar ...
1
vote
1answer
44 views

Some salts lower the vapour pressure of water - do any raise it?

Plain old NaCl salt can slightly lower the vapour pressure of water for a given tempertaure. Other salts such as CaCl lower the vapour pressure to a larger degree. Do any salts, or compounds of any ...
-3
votes
0answers
28 views

Instant ice or freezing capabilities [closed]

What chemicals when mixed or added to water can create ice, or reduce surrounding temperature greatly?
0
votes
0answers
47 views

The ways to determine if an ionic compound is paramagnetic or not

Find which of $\ce{Na2O2}$ and $\ce{CsO2}$ is paramagnetic. (Adapted from JEE advanced paper-1 2016, q.22) The given solution involves removing the cations and taking the anionic part, i.e. $\ce{O2^2-...
0
votes
0answers
36 views

Corrosive potential of molten ionic salt

I was looking at this video about fourth generation of nuclear reactors and one of developing concepts is molten salt reactor (MSR) where melted ionic salt replaces water as coolant and also acts as a ...
-5
votes
1answer
60 views

Is Avogadro's constant equal to 1? [closed]

The mole is defined to be exactly $\mathrm{mol}=6.02214076\cdot 10^{23}$ entities. Avogadro's constant is defined as $N_A=6.02214076\cdot 10^{23}\mathrm{mol}^{-1}$. Then why is it not usual to write $$...
3
votes
0answers
35 views

How can I store reagent under inert gas?

I need to store some aliquots of 2,3,5-tribromothiophene. I searched for how to store reagent under inert gas, And I found this : https://avantilipids.com/tech-support/faqs/protect-from-oxidation In ...
4
votes
0answers
22 views

Failure Cases of Adiabatic Approximation

We may exactly write the wavefunction of a molecular system as $$ \phi(r, R, t) = \sum_{k = 0}^{\infty} \chi_k(R, t) \psi_k(r, R) $$ where $r$ is the coordinates of electrons, $R$ is the coordinates ...
-2
votes
0answers
28 views

Nucleophilicity [closed]

When considering the strength of a nucleophile, electeonegativity is a factor to consider. A more electronegative atom will hold electrons more strongly and be less willing to donate their electrons. ...
4
votes
1answer
121 views

Relative abundance of mixture in mass spectra

In MS, as far as I know, the $y$-axis, relative abundance means the number of ions detected. Then does ratio of heights of two peaks stand for molar ratio, not mass ratio For example, given that I ...
-3
votes
0answers
38 views

How to electroplate iridium? [closed]

How to prepare the electrolyte from solid iridium? And what voltage/current is suitable to electroplated? What thickness per hour I can achieve?
0
votes
0answers
35 views

Why is effective nuclear charge used to explain the periodicity of size of atoms and ions?

Why is effective nuclear charge used for explaining the periodicity of size of atoms and ions, even though radius depends upon many other factors? The size of $\ce{Na+}$ is smaller than that of $\ce{...
-2
votes
0answers
21 views

The dot in KCl.MgCl2.6H2O [duplicate]

I've been trying to find the difference between coordinate compound and an adduct compound. The internet told me to believe that addict compounds are products of Lewis acids and bases (like [BF4]⁻) ...
7
votes
2answers
585 views

Why are protons more common than hydride ion?

I'm a high school student. I noticed $\ce{H+}$ ion is commonly present in my books while I didn't find any presence of $\ce{H-}$ ions in my books. However, I found on internet that $\ce{H-}$ also ...
-1
votes
0answers
26 views

Sni Mechanism of Alchohol and PCl5(cold) [closed]

I have searched the web, and have not found this mechanism. I wanted to know the correct charges on Oxygen and Phosphorus, as I am doubtful that in the image they are correct.
-4
votes
0answers
16 views

I want to scan 1 atom moving away from 2 atoms simultaneously while using the opt=modredundant option on the bond length between the 2 atom bonds [duplicate]

Using gaussian i want to scan one atom moving away from two atoms while optimizing the bond length between the other two atoms. I have been attempting to use a dummy atom to scan moving the two bonds ...
-2
votes
0answers
16 views

what is the lewis structure of CO+. Where is the positive charge present in the molecule? [closed]

In the molecule CO+, where is the positive charge in the structure? Is it with the carbon or the oxygen. What is the lewis structure of CO+
0
votes
0answers
22 views

Electron Gain Enthalpy of Noble Gases

Why does He(helium) has less positive electron gain enthalpy than Neon(Ne). The size of atoms increase down the zero group and also the effective nuclear charge increase down the group. Therefore the ...
-1
votes
0answers
36 views

Electric Spark Colour [closed]

https://www.google.com/url?sa=t&source=web&rct=j&url=https://en.m.wikipedia.org/wiki/Electric_spark&ved=2ahUKEwjzvPLAm4_yAhXEZSsKHVhLA9QQFjAXegQINBAC&usg=...
-4
votes
1answer
79 views

Nomenclature of Colors of precipitates and solutions

I have just started learning salt analysis in inorganic chemistry. In it i came across the names of colors of various precipitates and solutions. Why do they have prefixes such as "scarlet" ...
-2
votes
0answers
20 views

Does a change in Equilibrium position of a reaction affect the reaction rates of the forward and backward reactions?

In a reaction that is in an equilibrium state, when we change the pressure or concentration the equilibrium point changes. But does it affect the reaction rates of the forward and backward reactions?
0
votes
0answers
31 views

Chirality of conformations of butane

I have read that the conformations of butane are as follows: I came across a question about number of chiral conformations of butane. My Attempt : The total or fully eclipsed is achiral because it ...
0
votes
0answers
79 views

Can some liquid hand soaps smudge your eyeglass lenses?

My control variables are water hardness level, as I live in Florida, and I lodged at a Ritz Carlton also in Florida. I'm not, in any way, affiliated with any corporation herein. I'm not, in any way, ...
0
votes
0answers
20 views

respective posistion of d and p orbitals in a multielectronic species

we write the electronic configuration of atoms as [noble gas core]4s2 3d10.that is that due to energy considerations(aufbau principle) in multielectronic species. what i want to know is whether the 4s ...
4
votes
1answer
109 views

What is an intuitive explanation for the exponential form in the Arrhenius equation?

What is an intuitive explanation for the exponential form $\exp(-\Delta E/(kT))$ in the Arrhenius equation? While I know the reaction rate theory, I am puzzled by the origins of the form of the ...
2
votes
0answers
35 views

Deactivate lectins in beans by baking [closed]

Having dried uncooked beans, I read that the lectins can be deactivated by boiling and soaking for a while. What I could not find any information on is if dry baking beans would eventually deactivate ...
-1
votes
0answers
22 views

Bond Angle of Cl-S-Cl in SO2Cl2 [closed]

How can I explain that the bond angle of Cl-S-Cl in SO2Cl2 is 100 degrees, when SO2Cl2 has a tetrahedral geometry?
-4
votes
0answers
28 views

How many set of 4 quantum numbers are possible for the last electron of Sc? [Divide your answer by 2]

I am confused with this question. I don't know which one should be the last electron(the one in 4s or the one in 3d).I think it should be the one in 4s.
-2
votes
0answers
21 views

acid strength of triphenylmethane and acetylene [closed]

In a list of carbanion compounds stability, my teacher said that ph3C- is more stable than c2h- (carbanion of acetylene). However, checking the Ka values, we see that acetylene is more acidic. Why is ...
-4
votes
1answer
44 views

Does rearrangement occur in schmidt reaction? [closed]

I recently read about schmidt reaction in which a carboxylic acid is converted to an amine. While forming this, acyl carbocation $(\ce{RCO+})$ is formed, so does rearrangement takes place or reaction ...
-2
votes
0answers
35 views

Chemical reaction of cornstarch and shampoo [closed]

My class have a science experiment and they ask me what will happen if i mixed cornstarch and shampoo and what are the chemical reaction between them. If they mixed together what is the chemical ...
-2
votes
0answers
24 views

Molecular orbital theory vs Hybridisation theory

In molecular orbital theory, do the atomic orbitals undergo hybridisation or do the atomic orbitals just overlap with each other to form molecular orbitals. What I'm confused about is the difference ...

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