An electrically neutral entity consisting of more than one atom (n > 1). Rigorously, a molecule, in which n > 1 must correspond to a depression on the potential energy surface that is deep enough to confine at least one vibrational state. This tag should be applied to question about certain ...

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3
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0answers
14 views

Amount of substance of a molecule in a solute the same as amount of substance of constituent elements?

I've done absolutely no chemistry since high school. Now, 16 years later, I've been asked to look at some chemical analyses and I'm having trouble! Context: I've got a series of spectroscopy ...
1
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0answers
23 views

Chirality vs Resonance in chemical structure

In a reference book, chirality of a molecule is explained as "handedness", like our right and left hand, which are mirror images of each other. These are also called as enantiomers. The nearest clue ...
1
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0answers
13 views

What is the mean curvature of nitrates and nitrites?

I am reading the book Soft Matter Physics - Synthetic and Biological Self-Assembling Materials from Hamley and particularly page 201. I started to think how this packing occurs in case of molecules ...
1
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1answer
55 views

Is this a possible explanation as to why sigma bonds are stronger than pi bonds?

Sigma bonds form due to the axial overlap of two orbitals whereas pi bonds form due to their lateral overlapping. Since the former is more effective, we can say that sigma is stronger than pi. We mean ...
2
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1answer
18 views

How exactly do alcohol molecules dissolve in seawater?

The book "Lehrbuch der anorganischen Chemie" by Arnold F. Hollemann on page 47[link here][1] states that dropping 0.8g Alcohol (M = 46g/mol) in a sea or ocean would result in every litre seawater ...
2
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2answers
33 views

Does Uranium ore count as a mixture?

I'm doing an assignment where we must research the separation of a mixture to obtain a useful final product. I thought about the separation of Uranium from its ore after it has been mined, but I did ...
2
votes
0answers
43 views

Amplitudes and phases of transform of an image

I have recorded an image of a large macromolecule and after several types of image analysis, have obtained a rotationally averaged image, that is not quite perfect, but appears to show 6-fold ...
0
votes
1answer
64 views

How to represent a 3D model of cocaine?

For my AP Chemistry class we were told to make a molecular diagram that was "better than excellent" and the rest is up to us (we could choose the molecule and how we wanted to represent it). My group ...
1
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1answer
36 views

Volume Of A Nitric Oxide Molecule [closed]

So I was wondering what would be the best way to calculate a rough estimate for size of a Nitric Oxide molecule to use in comparison to a box. I was thinking volume would be the best method, but ...
-4
votes
1answer
60 views

Mass of “orange” in 25% orange juice [closed]

Hypothetical question: Knowing that orange juice has 25% concentration of orange. And knowing mass of juice which is 200g. What ...
-1
votes
1answer
36 views

On the molecular level, how do catalysts work? [closed]

I already know what catalysts do (lower activation energy requirement for a reaction), but how exactly are they able to do that (on a molecular level)?
10
votes
7answers
2k views

Are there any good examples of commonly ingested molecules that contain particular toxic individual elements?

In the house on my own and an article popped up on my feed with the following statement: While the Government has insisted the chemical is safe, cadmium is recognised as a cause of lung cancer ...
-2
votes
2answers
64 views

Why is O2 enough to form a mole of Oxygen? [closed]

I understand that this is the most basic knowledge of moles, however I'm still unsure - according to easy research, $\ce{O2}$ forms a mole of Oxygen. As a mole is $6.022*10^{23}$, exactly what on the ...
2
votes
2answers
46 views

What's the reason for discrepancy between DFT calculated image and NC-AFM-acquired one in this article?

Looking at the images in this article, I've noticed that the molecule electron density images showed as calculated via DFT look very symmetric, while those obtained by NC-AFM appear somewhat ...
2
votes
1answer
63 views

Is oil shinier than water? Why?

The physics part: The part that talks about being shiny, I agree, is mainly physics. But proceed in my question, and you'll see how it's a chemistry one. We know things are shiny if they either ...
2
votes
1answer
87 views

Volume of 1 Mole of Liquid Water

I am doing some rough calculations to test my understanding of elementary chemistry. In what follows, I calculate the volume of one mole of liquid water at about $4~^\circ\mathrm{C}$ and ...
2
votes
1answer
46 views

Do molecules with carboxyl groups have properties of carboxyl's sub-functional-groups?

We're learning about functional groups of different organic molecules, and there are some I'm confused about: carboxyl, carbonyl, and hydroxyl. I was looking online but I couldn't find a direct answer ...
1
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0answers
39 views

First ionization energy of hydrogen molecule

If we have the dissociation's energies of hydrogen molecule $H_{2}$($D_{0}$) and the corresponding molecule ion $H_{2}^{+}$ ($D_{1}$) together with the first energy of ionization of hydrogen atom ...
0
votes
0answers
41 views

Molecular structure of all periodic table element molecules exceptional cases etc

I am searching about some basics in chemistry. I was looking for the molecular structure of all periodic table element molecules. eg: Hydrogen molecule: as $\ce{H2}$; structure: I was able to find ...
4
votes
3answers
79 views

Can a single monomer be a macromolecule? If so, when?

In our science class, we're learning about the four fundamental macromolecules in every living organism: carbohydrates, proteins, lipids, and nucleic acids. Our class definition of a macromolecule ...
6
votes
2answers
268 views

How to know whether s-p mixing will happen in heteronuclear molecules?

How do I know whether s-p mixing would occur in some diatomic heteronuclear molecules like CN, CO, NO etc?
5
votes
2answers
697 views

Using MO theory, give an explanation for the C-C bond length in cyanogen

1. The problem statement, all variables and given/known data 2. The attempt at a solution I know that the MO diagram for CN- is this: I am unsure how to draw the MO diagram for cyanogen. I know ...
2
votes
1answer
830 views

Draw a simplified MO diagram for the pi system of Methyl vinyl ether

My attempt at the answers: i) 2 bond pairs and 2 lone pairs on oxygen atom therefore bond angle of slightly less than 109.5 degrees, around 104 degrees. ii) 120 degrees bond angle therefore sp2 ...
10
votes
1answer
440 views

Why six C atoms are usually seen in cyclic compounds?

When it gets to Carbon-based molecules, one very possible structure when there are more than six C atoms is the hexagon; though not mostly perfect, it emphasizes that six Carbon atoms tend to bond ...
0
votes
1answer
13 views

Does STED microscopy allow us to see reactions happening on a substrate

This years nobel prize for chemistry went to nanoscopy using STED as a control mechanism. I have seen the atoms/molecules of a lattice vibrating as shown by Stefan W Hell in a presentation at some ...
1
vote
1answer
64 views

Stereo Isomerism - syn/anti

I was studying the types of stereo-isomerism E-Z, Cis-Trans and then I come across syn-anti stereo-isomerism this one is giving me a bit of fight in understanding, especially where lone pairs are ...
16
votes
2answers
795 views

Proper typography of “NOx”

I am a journal typesetter, and recently I came to a problem that I'm not sure I know to solve. The question is how to properly typeset the "NOx" abbreviation for nitrogen oxides. Which is ...
4
votes
1answer
105 views

Why is water transparent?

Some substances like Copper Sulfate for example have vivid colors. But why is water transparent? Does it not emit any visual light from the electromagnetic spectrum?
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votes
1answer
74 views

How would you find the mass in grams, if you only know the number of particles of a portion of the formula? [closed]

If you were given a question like below: What is the mass in grams of a sample of $\ce{Fe2(SO4)3}$ that contains $3.59 \times 10^{23}$ sulfate ions, $\ce{SO4^{2−}}$ ? The molar mass of ...
2
votes
1answer
24 views

definition of relative atomic mass

I found out there are 2 definitions of relative atomic mass. First definition is Ar is the mass of 1 atom of an element relative to 1/12 the mass of carbon-12 atom. It can be found in any chemistry ...
0
votes
1answer
527 views

Chemical composition of petrol

What is the chemical composition of petrol? What are the molecular available in petrol? Some time which is marked with 95% octane. So what is the remain element occupied 5%?
0
votes
0answers
41 views

Relating Molecular Orbital Theory and Valence Bond Theory

As I have studied both the theories only superficially, I am unable to correlate them. I would like to know the link between the two.
0
votes
1answer
72 views

Molecular Orbital Theory and No. of bonds

The order of filling of molecular orbitals $\ce{O2}$ by MOT is this : But from it, how can I deduce that there is one sigma and one pi bond in an oxygen molecule ?
2
votes
2answers
32 views

How can we confirm the number of protons in an atom?

The periodic table tells us that there are 6 protons in a carbon atom. Is there a way to verify this first-hand? Or are we just expected to believe it unquestioned?
4
votes
1answer
2k views

What holds atoms together?

1.I know atoms are held together by Ionic and Covalent bonds and i understand the ionically bonded atoms are held together by electrostatic forces. What about covalent bonds? 2.How are molecules of ...
-1
votes
1answer
58 views

Dipole, Symmetrical, ASymmetrical [closed]

I don't understand what a dipole is, I kind of have an idea but not exactly. Also, how do you know if a molecule is Symmetrical or ASymmetrical. For example, the following: $\ce{O2}$ $\ce{H2O}$ ...
1
vote
1answer
241 views

Converting from Grams to Molecules

I was doing some problems from the textbook on converting between units using dimensional analysis and I came across this problem. A vat of Hydrogen Peroxide ($\ce{H2O2}$) contains 455 grams of ...
4
votes
3answers
176 views

What actually is the Wavefunction?

I am aware that the square of the Wavefunction gives the probability density of finding an electron at a particular point in space. I have also heard that it's a complex number but since it's a ...
2
votes
1answer
50 views

Find the partial pressure in a container

I have an air mass which consists of 78.1% $\ce{N_2}$, 20.9% $\ce{O_2}$, 0.964% $\ce{Ar}$, and 0.0378% $\ce{CO_2}$ in a container which volume $\mathrm{V=40~L}$ at a temperature $\mathrm {T = ...
3
votes
1answer
97 views

Electrolysis of Beer

Electrolysis of water, means that the water is separated into hydrogen and oxygen. As beer also includes water, I initially thought electrolysis of beer would cause the water to separate, and the ...
2
votes
1answer
70 views

Can you calculate the properties of a substance based soley on its atomic properties?

I'm trying to write some software that I can use to determine, roughly, what the physical properties of a pure substance are. I know I could just use a database of the known properties of each ...
0
votes
1answer
29 views

Chemical nomenclature of ions

I'm a very beginner in chemistry. The book I'm studying says that an ion is an atom, or a collection of atoms, that has an electric charge, then it writes about the difference between molecules and ...
3
votes
2answers
77 views

Why does water break salt really

A kid asked me this question just the other day, and I said that the positive part of $\ce{H2O}$ attracts the negative $\ce{Cl}$ ion and the negative part of the $\ce{H2O}$ attracts the positive Na ...
2
votes
1answer
51 views

About the way chemicals and molecules are represented

The standard way of representing molecules with letters like $\ce{C}$ for Carbon, $\ce{O}$ for Oxygen etc.; and a lot of lines and double lines like a graph from Graph theory where each letter is a ...
3
votes
1answer
831 views

Phenyl vs phenol functional group?

Phenyl is a functional group with an aromatic ring bonded to another group. And, phenol is a molecule that is just a phenyl bonded to a hydroxyl group. However, some sources consider phenol itself a ...
4
votes
2answers
157 views

Nitrogen dioxide dimerization

$\ce{NO}$ can't dimerize and that is explained because the free electron is in an antibonding orbital. The same is true for $\ce{NO2}$, but it can dimerize, how?
3
votes
2answers
2k views

Why are least electronegative elements usually in center of lewis structure

Many sources state that one of the primary rules for molecular structures is that the least electronegative element is in the center. However, none of them explain why this is the case. Is this ...
2
votes
2answers
58 views

Why is it O-Cl-O and not O-O-Cl?

I'm currently preparing my exam and while I did never think about this question during the course, it begins to confuse me right now... Why is it the structure of $\ce {ClO_{2}-}$ like $\ce {O-Cl-O}$ ...
1
vote
0answers
27 views

H2, dipole transitons [closed]

I'm a not a chemistry expert, so please forgive me if what I write is not entirely correct. I come from an astrophysics background and in several astrochemistry papers it is mentioned that dipole ...
0
votes
2answers
45 views

Molecules that get charged in Water

I am a chemistry super noob and I was watching a MIT video where the professor states that: "Certain molecules become charged when they come in contact with water in the natural state" Can someone ...