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3 views

Why chlorine ion is more stable than chlorine atom?

In heterolytic cleavage , For instance,NaCl breaks in two fragments Na+ and Cl-. If Chlorine is full filled because it takes one electron from sodium ,now chlorine is full filled then why further ...
2
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2answers
15 views

If you placed silver metal into silver nitrate, would a reaction occur?

thinking about oxidation and reduction, what happens to the silver metal and the silver ions?
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0answers
8 views

Organic Chemistry, carbonyls

https://imgur.com/a/WmTInTa I'm a bit lost on how to do this, for Product C I can see two things happening: 1) The -OCH3 attacks the alpha hydrogen, but that doesn't really make sense as then you ...
2
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1answer
14 views

Check My Beginner's Guide to Shells, Energy Levels, Subshells, and Orbitals

I am a beginner trying to summarize what I've learned about: Shells Energy Levels Subshells and Orbitals all at the high school level. Unlike related threads, I'm going to try to: Define each word ...
0
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0answers
11 views

All-Gauche Alkane: Is It Possible?

I've learned about anti and gauche conformations throughout my scholastic journey, and I have heard often that straight-chain alkanes always adopt an all-anti conformation in their lowest energy state....
3
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0answers
7 views

Why is 4-t-butyl aci-nitro cyclohexane stable whereas aci-nitro cyclohexane is not?

During my PhD, about fifty years ago, I had reason to use 4-t-butyl aci-nitro cyclohexane and found it to be remarkably stable. Usually aci- nitro compounds revert to nitro compounds very quickly ...
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0answers
5 views

what is the mechanism of hydrolysis of alkyl cyanides

I am very much confused about the mechanism of hydrolysis of cyanides, in my book it is given that hydrolysis of cyanides in presence dil HCl or alkalies gives carboxylic acid whereas on hydrolysis ...
-1
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0answers
13 views

Half life problems with regards to carbon 14 and carbon 12 isotopes

If the ratio of carbon 14 to carbon 12 was only 0.326 of that in the atmosphere today. What is the age of the substance if the half life of carbon 14 is 5700 years.
0
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1answer
18 views

How does one dilute sulphuric acid (1.28sg@25ºc 460g/L) to 3 M Sulphuric Acid?

Thanks for looking. The extent of my research around the issue so far. SA sg table but wrong temp 60f not 77f/25c http://www.sschemical.com/wp-content/uploads/2013/05/Conversion_Table.pdf From ...
3
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2answers
23 views

Chemical engineering: recycle unreacted ethene

The question is this: You want to make oxirane from ethene and oxygen gas: $$\ce{2 C2H4 + O2 -> 2 C2H4O}$$ The flow into the reactor is constant at $\pu{200kmol/h}$ of $\ce{C2H4}$ and $\pu{...
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0answers
12 views

How does magnisium carbonate's dissolution change with the temperature of water?

What I am trying to figure out after not really using or remembering anything about chemistry for like 5 years is whether magnesium carbonate dissolves "better" in hotter water or colder water because ...
-1
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0answers
21 views

Confused regarding aromaticity

I can understand the aromaticity in the second but can't in the first structure. The second structure is aromatic since it has a continuous conjugation in the rings, but the first structure has no ...
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0answers
21 views

Oxidation reduction problem [closed]

For the following reactions, identify the substance oxidized, the substance reduced, the oxidizing agent, and the reducing agent: $\mathrm{(a)}\quad\ce{2HNO3 + 3 H3AsO3 → 2NO + 3H3AsO4 + H2O}$ I ...
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2answers
27 views

Addition of acid and base to buffer system

So I was doing my chemistry assignment and became stuck. Can I get some help? a) Calculate the pH of a buffer system that contains 0.40 M of NH3(aq) and 0.50 M of NH4Cl(aq) . Note that the Kb value ...
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0answers
15 views

H NMR splitting in pure sample

Why does a pure product create an H NMR spectrum without visible splitting (smooth peaks of various heights and widths) versus the same product with impurities present has a spectrum with clear ...
-1
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0answers
17 views

What does 3-(Trimethoxysilyl) propyl dimethyl octadecyl ammonium chloride do? [closed]

Someone recently made the claim to me that 3-(Trimethoxysilyl) propyl dimethyl octadecyl ammonium chloride was significantly more effective in dealing with the Corona Virus outbreak because it could "...
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0answers
14 views

Internal energy with microscopic kinetic or potential energy

For every process in an isolated system that has no macroscopic kinetic or potential energy, ∆E=0 Will this statement be true if instead of macroscopic it were microscopic?
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0answers
14 views

Do esters and amides hydrolyze in neutral medium

It is well known that esters and amides readily hydrolyze in acidic/ basic medium. I want to know if thay can undergo hydrolysis in neutral medium as well. In other words, does ph only affect rate of ...
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0answers
14 views

Generate Surface with CubeFile from Gaussian in VMD or other free programm

I asked a question before, about how to save a mapped surface from GaussView. I don't get an answer, so I get much deeper in my internet research about it again. Now I want to try to create a mapped ...
1
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1answer
25 views

How to introduce an imino-nitrogen atom? From a carbonyl and double bond to an imino bond containing ring

I am working towards a natural product. Presented are three intermediate compounds. After oxidation of the hydroxyl to a carbonyl, I want to introduce an imino-nitrogen atom into the structure. This ...
2
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1answer
38 views

I am seeing Doublet of Doublets peaks when I should see just a doublet

The following is a tutorial question I need to do: I initially thought the answer was isobutyl formate (CAS:542-55-2) but what confuses me is the dd peak at $\pu{3.9-4.0 ppm}$. To my knowledge, ...
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0answers
9 views

I want to clarify a doubt regarding polymers [closed]

What is Glass transition temperature? Justify glass transition temperature of Polyvinyl Alcohol is greater than Polyethylene
-1
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0answers
8 views

radical calculation with gaussian [closed]

I have neutral molecule (e.g. C2H2O) at ground state and I want to calculate its total energy with DFT method. I use Gaussian program. I wanna ask how it is possible to calculate it appearance ...
-3
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0answers
17 views

Why is Beryllium intensely hydrated if its reduction potential is so low? [closed]

I just read these two facts and they don't match up. The reduction potential of Be is much less than rest in the group. This indicates that beryllium is much less electropositive than the others and ...
5
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1answer
82 views

Open resource for spectroscopic raw data

Is anyone aware of reliable resources (ideally public) which allow the user to download the raw spectroscopic data such as infrared spectrum of small organic molecules, or rotational spectrum of HCl/...
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0answers
27 views

Why is HI more acidic than HF? [duplicate]

The more will be the polarity, the more will be the solubility, and the more will be the acidity too between HF and HI. Can anyone please tell me which is more acidic between HF and HI?
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0answers
18 views

Hybridization theory (orbitals used in different hybridizations)

Why is $d_{x²-y²}$ orbital used in $sp^3d$ (square pyramidal geometry) while $d_{z^2}$ orbital in $sp^3d$ (trigonal bipyramidal geometry)? I came across this information while reading J.D.Lee Concise ...
1
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0answers
24 views

Adding an essential oil to WHO Handrub Formulation [closed]

I'm not a chemist, so I prefer to ask this question to some people, who definitely have knowledge in that area. WHO Handrub Formulation is available here. Ingridients: Ethanol 96%, Hydrogen peroxide ...
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0answers
13 views

Mechanism of bromination of phenol [closed]

Please explain the mechanism of bromination of phenol by Naoh/Br² including all intermediates. (I actually need these )
-1
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0answers
28 views

Are Br2 and Cl2 electrophiles [closed]

Are $\ce{Br2}$ and $\ce{Cl2}$ electrophiles Since they have vacant d-orbitals, they can accomodate more electrons and can behave as electron deficient species. Thus should be electrophiles.
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2answers
48 views

Antoine law and ideal gas law

I have the following question: A $100\ \mathrm{ml}$ sealed flask with $60\ \mathrm{ml}$ acetonitrile is heated to $140\ \mathrm{^\circ C}$. The boiling point of acetonitrile is $82\ \mathrm{^\circ ...
1
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0answers
34 views

Does orientation matters to this extent in reactions?

In the above question I know that the three reactions involved are $\mathrm{S_N2}$ reactions and therefore there shall thrice inversion of the substitute. So, I got the solution for the MCQ as: ...
-2
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0answers
18 views

Why do transition metals have multiple oxidation states? [closed]

I know it is to do with the subshell configuration of the electrons, but what is the actual answer? Thank you :)
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1answer
15 views

For an electron arrangement diagram, is it necessary to show the inner electron shells or is it customary to only show the valency electrons?

Which electron arrangement diagram is correct? The one that shows all electron shells or the one that only shown the valence electron shell?
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3answers
36 views

Are aqueous (aq) elements involved in equilibrium?

The reaction was something like this: A (s) + B (l) yields to C (aq) + D (aq) The question asked: If you added another D, which way would the equilibrium shift to? I answered that it would have no ...
2
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0answers
23 views

Molecular similarity using Tanimoto coefficient

I'm trying to use a method for evaluating similarity of molecules. I have seen many publications in the machine learning community have used Tanimoto coefficient. However, when I read about it, it ...
12
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3answers
2k views

Why Isn't the American Nickel magnetic?

I never thought that modern American nickels actually contained nickel anymore. However, according to this site, the coins actually do contain 25% Nickel, the rest being copper. And yet, No US coin ...
-2
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1answer
24 views

If all the points on my graph fit on a logarithmic and polynomial trend line, how do i justify which trend line i should use? [closed]

My graph is mass of deposit vs concentration. The mass of deposit increases with concentration.
0
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1answer
22 views

Can Potassium Carbonate be used to reduce Calcium hardness in water

I have a solution of KCl 20g/l (2%) and 500mg/l Ca, To reduce the hardness, Na2CO3 is normally used, but can I use K2CO3 instead?
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0answers
6 views

How many g of Al(NO3)3 would be in 0.089 L of a 0.63 M solution of Al(NO3)3? [closed]

I'm stuck on this question. How many g of Al(NO3)3 would be in 0.089 L of a 0.63 M solution of Al(NO3)3?
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0answers
22 views

What is the best method to seperate phenol and benzoic acid?

Question: What is the best method to separate phenol and benzoic acid? I know that The phenol and Benzoic acid can be separated via their varying solubility, by heating the mixture in H2O to dissolve ...
1
vote
1answer
12 views

Methods to quantify lead(II) concentration in water on the ppm/ppb level

While there are several ways to quantify metal concentrations in water, a lot of them are only specific to select metals. For example, there is the orthophenanthroline method for quantification of Fe(...
-2
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2answers
68 views

What is really the number in the periodic table?

I learning basic chemistry and i have a doubt. I have this definitions Molar mass: Is the mass of $6.022\times10^{23}$ atoms of a chemical element and its unit of measurement is $\mathrm{g/mol}$. ...
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0answers
9 views

Acids and Bases (Buffers) [closed]

In order to create a buffer, you need to add conjugate acid to the base solution you created. How much methylammonium chloride would you have to add so that the concentration of the conjugate acid is ...
-2
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0answers
11 views

Chemical equilibrum [closed]

An equimolecular mixture of NH3 and O2 is contained in a container. After the oxidation reaction took place to obtain NO, the equilibrium is established: 4NH3 + 5O2 ⇌ 4NO + 6H2O + Q It is found that ...
2
votes
1answer
18 views

Can o-phenanthroline be used as a complexing agent for lead(II)?

I’ve been trying to find a method to perform a spectrophotometric analysis to determine lead concentration (on the ppm level). This would require some chelator capable of forming a coloured complex ...
-1
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0answers
19 views

How does the nucleophilicity of a leaving group affect SN1/SN2 reactions?

I was reading about SN1 and SN2 reactions and I was wondering how nucleophilicity of the leaving group contributed to the reaction? For example, if I react iodoalkane with a strong nucleophile (but ...
-2
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0answers
17 views

What is the pressure of the dry gas alone? [closed]

A 550.mL sample of oxygen is collected over water at 25ºC and 560.0 torr pressure. Vapor pressure of water at 25 ºC = 23.8 torr)
1
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0answers
22 views

thermodynamics problem [closed]

The boiling point of a substance $X$ at 1 atm pressure is $500 k$ . The enthalpy of vapourisation at the boiling point of $X$ (l) is 80 kj/mol .The molar specific heat of $X(l)$ = $5 × 10^{-3}$ kj/mol ...
4
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0answers
38 views

can a vapour denser than air evaporate in a closed chamber?

Imagine a closed container filled with air. There is some liquid substance on a bottle placed on the floor of the container. Let's heat the liquid until it starts to evaporate. Let's say 20% of the ...

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