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16
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2 answers
How do I create a spreadsheet containing the coordinates and predicted bond angles, molecular properties, torsion properties, etc of a molecule?
On a previous answer here (https://chemistry.stackexchange.com/a/30841/876) I was informed in the comments that OpenBabel & Python terminal could be used to print the data contained in the property matrices of Avogadro (more info can be found here…
Josh Pinto
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16
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1 answer
What do typical results from inductively coupled plasma mass spectrometry (ICP-MS) look like, and how do I interpret them?
I have a degree in chemical engineering and remember having seen a inductively coupled plasma mass spectrometer (ICP-MS) during the laboratory part of a chemistry course I took while at university, but it is many years ago. Now I would like to know…
anon
16
votes
1 answer
Basicity Alteration Due To Ortho Effect In Methoxy Aniline System
I wanted to ask something more in reference to this question.
Suppose instead of toluidine, 2-methoxyaniline and 3-methoxyaniline are present. Now, why is 2-methoxyaniline more basic than 3-methoxyaniline (even though 2-methoxyaniline has reduction…
user14857
16
votes
1 answer
Failed synthesis of aspirin due to excess sulfuric acid
Last week, I tried synthesizing acetylsalicylic acid - the reaction is shown below - using $\ce{H2SO4}$ as a catalyst. However, as the title suggests the synthesis failed as I used too much $\ce{H2SO4}$ - approximately four times more than the…
studen
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16
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3 answers
Difference between intermediates and transition states
Can someone please explain what exactly the difference between an intermediate and a transition state is?
I understand that they are formed as part of the process in converting the reactants to products in a chemical reaction. Other than that, all I…
tkhanna42
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16
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1 answer
Resonance in carbocation derived from allenes
During a reaction if addition on one of the $\pi$ bonds of an allene (containing even number of $\pi$ bonds like $\ce {H2C=C=CH2}$) takes place then a carbocation is formed. To decide the position of the positive charge, we look at the stability of…
Aditya Sriram
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3 answers
Comparing SN2 reaction rates
I've read in a book that the main factor for determining SN2 reaction rate is steric hindrance. The lesser it is, the faster the reaction.
So consider this question:
$\ce{KI}$ in acetone undergoes SN2 reaction with each of $\ce{P,Q,R}$ and…
Help needed
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Why are the masses of atoms less than the sum of their subatomic particles?
The mass of carbon-12 is $\pu{12 u}$ by definition. However, one carbon-12 atom comprises 6 neutrons (each weighing $\pu{1.0087 u}$), 6 protons (each weighing $\pu{1.0072 u}$), and 6 electrons (each weighing $\pu{0.0005 u}$), which all add up to…
user930067
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4 answers
Why are solid phase organics often conjugated to HCl?
Many uncharged organic compounds are sold in solid phase with HCl conjugate - e.g. the antihistamine diphenhydramine.HCl or the derivitizing agent pentafluorobenzyl hydroxylamine.HCl, among many others. Assuming the compound will be dissolved at…
Drew Steen
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16
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9 answers
How can 30 ml of water be heated in less than 10 seconds?
How is it possible to heat a tiny amount (30 ml)[1] of water to a high enough temperature to make a coffee, in less than 10 seconds and possibly instantly?
Most heaters that I know of heat water in no less than 90 seconds (induction heater) or 3…
Alper Turan
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16
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7 answers
What's the difference between perfect and ideal gas?
There are all kinds of different dinstinctions in the internet, and I'd like to see what you guys thought.
Actually, I've been asked if the heat capacity of an ideal gas es independent of temperature. I've said no, even though it's practically…
DLV
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1 answer
What is the chemistry behind this "petrol from air" technology?
A recent news report in the UK claimed a breakthrough in making a petrol equivalent from carbon dioxide and water:
A small British company has produced the first "petrol from air" using a revolutionary technology that promises to solve the energy…
matt_black
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16
votes
2 answers
How do atoms of noble gases bond with each other?
Noble gases have full electron shells, which virtually blocks any other element from bonding with it. However, I've heard about cases where they bond to each other - for example, helium can apparently form a dimer $\ce{He2}$.
How is this possible?
unbindall
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2 answers
Why does microwave heat up things so much more quickly than visible light?
I wonder why microwave has more "energy" to heat things up than visible light does. Microwave has a much longer wavelength, therefore should supposedly has less energy than visible light.
But does wavelength and frequency really have to do with how…
most venerable sir
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16
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2 answers
Inductive effect and hyperconjugation - one elephant, different parts?
Are the inductive effect and hyperconjugation both different ways of looking at the same phenomenon - i.e. methyl groups donate negative charge for example. Inductively we can argue that carbon is of greater electronegativity than hydrogen, and so…
Dissenter
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