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2
votes
2answers
9 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?
0
votes
0answers
2 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
votes
1answer
12 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 ...
5
votes
1answer
5k views

Why is Promethium the only radioactive Lanthanide?

Why is it that only Promethium (Pm) is the only radioactive lanthanide? I was trying to figure out what percentage of all radioactive elements in the Periodic Table the f-block accounts for, when it ...
5
votes
2answers
12k views

Preparation of picric acid

My textbook says "Nowadays picric acid is prepared by treating phenol first with concentrated sulfuric acid which converts it to phenol-2,4-disulfuric acid and then with concentrated nitric acid to ...
0
votes
0answers
7 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 ...
3
votes
2answers
22 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{...
-1
votes
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 ...
0
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0answers
9 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....
2
votes
1answer
46 views

Why can DAP be used to elute a protein in affinity chromatography?

A little background: as part of my bioinformatics degree I have to take Protein Chemistry course, but I miss chemistry basics (have CS background), so that's why I'm asking the following question. We ...
1
vote
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
votes
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 ...
0
votes
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 ...
0
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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 ...
-2
votes
1answer
43 views

Preparation of potassium cyanide from potassium ferrocyanide via HCN method

Does anyone have any experience with the preparation of potassium cyanide from potassium ferrocyanide via HCN method? I did some math and am going to proceed eventually, any advice would be welcomed. ...
-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.
12
votes
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 ...
-1
votes
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 ...
2
votes
2answers
101 views

Why when deriving the Clapeyron equation can you assume that dH = dq, as surely the pressure is not constant?

Part of the Clapeyron equation involves replacing $\Delta S$ with $\Delta H/T$. I can see the step from $\Delta S$ to $\Delta q/T$ but I'm not sure why you can replace $\Delta q$ with $\Delta H$. From ...
1
vote
2answers
185 views

Is the following molecule aromatic or antiaromatic?

This molecule has the same chemical formula $\ce{C20H10}$ as corannulene (which also is non-planar) and corannulene is aromatic, so I'm pretty sure that this molecule should be aromatic too. I tried ...
-1
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0answers
20 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 ...
0
votes
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 ...
17
votes
5answers
2k views

Is the carbon atom in the carbon dioxide molecule partially positive?

I had a question about nonpolar molecules that have symmetrical dipole vectors. Let's take $\ce{CO2}$ as an example. Each of the $\ce{C=O}$ bonds are pulling in the opposite way. My teacher says that ...
9
votes
1answer
135 views

DIY hand sanitiser solution forms spongy substance

I am trying to make my own hand sanitiser since it’s sold out everywhere. The formula I use is 1 part aloe vera gel in 2 parts 100% isopropyl alcohol. The problem is when mixing the two, the solution ...
0
votes
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 ...
0
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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 ...
2
votes
1answer
51 views

Could coating silver inside of a cuvette be used for SERS?

I understand that molecules adsorbed to a coinage metal surface experience plasmonic enhanced Raman shifts and I have a spectrometer that I would like to perform SERS measurements with but do not have ...
-1
votes
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 "...
2
votes
0answers
101 views

SERS Gold nanoparticles performing poorly in organic solvents?

We have been working with some organic solvents lately and noticed a sharp decrease in surface-enhanced Raman spectroscopy (SERS) performance from our gold nanoparticles deposited in an organic ...
2
votes
1answer
258 views

Interaction between soy milk and coffee producing bubbles

I noticed when I poured my soy milk (which I shook as per the directions on the carton) into my coffee, a large number of very fine bubbles rose to the surface. What causes this? Is there a chemical ...
0
votes
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?
-1
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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 ...
2
votes
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, ...
0
votes
1answer
42 views

Are Hansen solubility parameters available for inorganic salts or ionic molecules?

Are Hansen solubility parameters available for inorganic salts or ionic molecules (e.g. potassium oleate, potassium stearate, sodium dioctyl sulfosuccinate (AOT), sodium dodecyl benzol sulfonate (SDBS)...
0
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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 ...
3
votes
1answer
980 views

Which is the strongest base relative to ammonia?

Among these bases, ammonia methylamine ethylamine dimethylamine trimethylamine quinuclidine 1) Which is the strongest base relative to ammonia? Why? 2) Which conjugate ...
3
votes
1answer
3k views

Ratio of copper(II) ions to EDTA?

What is the ratio of copper(II) ions to EDTA in a $\ce{[Cu(EDTA)]^{2-}}$ complex? I know that EDTA forms up to 6 coordinate bonds with the central atom, but is that what they are asking for with "...
1
vote
0answers
110 views

Difference in major product of sulphonation of phenols

When phenol is sulphonated by fuming sulfuric acid at a lower temperature, the ortho product is the major whereas at higher temperature the para product is formed as the major. Why does this happen, ...
0
votes
2answers
65 views

Finding the pH of a solution

What are the steps we go about in finding the pH of a solution of Strong base and a salt of a Weak base and Strong acid? Here is the question that I've been given Find the pH of a solution made ...
9
votes
2answers
2k views

Why is tin(II) fluoride more effective in turning apatite into fluorapatite?

In more powerful toothpastes, like Crest Pro-Health, stannous fluoride is used in place of sodium fluoride. According to Wikipedia: Stannous fluoride converts the calcium mineral apatite into ...
5
votes
1answer
77 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/...
7
votes
3answers
80k views

Why is DNA negatively charged and what makes it so?

What part in the strand contributes to the overall non neutral charge? DNA is not isolated in the body, so what keeps it stable while being charged? Why is it important for DNA to be charged?
-2
votes
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 $\mathrm{g/mol}$. ...
1
vote
1answer
84 views

Trends in solubility of group 2 nitrates

In my lab report, we are required to explain the trends in solubility of group 2 salts, going down the group. I had explained all of the trends except one, group 2 nitrates. The following is the data ...
-2
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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
0
votes
1answer
24 views

Conditions for Complete hydrolysis of salt [closed]

My text book says that the cations (or anions) which are stronger than hydronium ion(or OH-) and their conjugate base (or acid) being very much weaker than water show complete hydrolysis. While the ...
-3
votes
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 ...
-1
votes
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 ...
1
vote
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
votes
0answers
26 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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