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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MO for $N_2^{2-}$

Could someone please show me the MO diagram for $N_2^{2-}$? What I did was since N has 5 valence $e^{-}$, then $N_2$ must have 10, and $N_2^{2-}$ must have 12. And N has $s$ and $p$ orbital mixing. So ...
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0answers
10 views

What radius best represents reaction distance?

Molecules must be within a certain distance for a reaction to begin as well as satisfying a myriad of other factors. Whilst the exact distance varies from reaction to reaction, is their any ...
0
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0answers
12 views

Why are the axial bonds in a PBP geometry molecule longer than those in a molecule with TBP geometry?

Why are the axial bond lengths greater than those of the equatorial bonds in a pentagonal bi-pyramid (PBP) geometry molecule; but the opposite is true for trigonal bi-pyramid (TBP) geometry molecules? ...
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0answers
7 views

Interaction radius of a molecule

What is the most commonly used radius of an atom or molecule to describe the area that must touch another area of another molecule for the two to react. Is there one radius that always works or does ...
2
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1answer
72 views

Why might two different chemical structures smell the same?

From what I understand, it is the functional group attached to a structure that determines the odor it will give off, for the most part. Which explains why two similar molecules, except for their ...
8
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2answers
56 views

What causes spray cans to get cooler when shaken?

I've been searching the web for this phenomenon and surprisingly I found only one post about it. And the reply to this question about canned air begins with words: I don't know about the shaking ...
6
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2answers
315 views

Explain the formation of replicators to a layman

I am reading The Selfish Gene by Richard Dawkins. I am on chapter two. He speaks of the observation of the formation of amino-acids when you simulate environmental conditions of primordial ...
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0answers
37 views

Diatomic Molecules/Elements

What is the difference between diatomic molecules and elements? Also, If oxygen is element of a single atom, then what makes it a diatomic element? But, then I read that a single oxygen atom can ...
3
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1answer
32 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 ...
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0answers
31 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 ...
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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 ...
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1answer
64 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
35 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
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0answers
46 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
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1answer
97 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
37 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 ...
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1answer
70 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 ...
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1answer
38 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)?
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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 ...
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2answers
66 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
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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
65 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
102 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
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1answer
47 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 ...
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0answers
41 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
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0answers
45 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
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3answers
80 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
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2answers
314 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
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2answers
741 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
892 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
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1answer
449 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
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1answer
74 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
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2answers
796 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
116 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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1answer
80 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
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1answer
719 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
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0answers
46 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
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1answer
82 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
3k 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 ...
-2
votes
1answer
59 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
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1answer
245 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
179 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
104 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
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1answer
73 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
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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 ...