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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13
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1answer
662 views

Are long Oxygen molecules possible?

Are large oxygen containing molecules possible? Either large rings, or chains with hydrogen atoms at the ends. Like this: $\ce{H-O-O-O-O-O-O-O-O-O-... -O-O-O-O-O-H}$
1
vote
1answer
35 views

At what point does Avogadro's law not apply?

A mole of hydrogen gas takes up 22.4 L, but so does a larger molecule like $\ce{CO2}$. Methane ($\ce{CH4}$) is an even larger sized molecule, but a mole of it will still take up 22.4 L. I would assume ...
2
votes
1answer
33 views

Molecules Molecules?

Question is simple I was just wondering if for example If I have a water molecule (H2O) and I have hydrochloric acid and they will get bound together, would they become a molecule made of molecules, ...
7
votes
0answers
48 views

What makes water a liquid (when it is)?

I'm curious about what the minimal conditions for some collection of water molecules to be liquid water are. What is the minimum number? What sort of bonds must hold? What other sorts of things I ...
6
votes
1answer
90 views

Why does SO2 have a larger bond angle than H2O, H2S, and NH3

So we have to find which of the follwing compounds has the smallest bond angle: $\ce{H2O}$, $\ce{H2S}$, $\ce{NH3}$, $\ce{SO2}$. So L $\propto \frac{1}{BA}$ where $L$ is the number of lone pairs and ...
0
votes
1answer
27 views

Identifying the number of bonding and lone pairs without a dot and cross diagram

I've just learned how to predict the shapes of molecules in class today using VSEPR theory. I would like to ask is there anyway to find the number of bond pairs and lone pairs without drawing a ...
0
votes
1answer
28 views

How does Le Chatelier's principle work in a gaseous system?

My textbook said Le Chatelier's principle applies normally to gases but there is no explanation. I did some googling and it said if you increase the pressure, it will shift to the side with less moles ...
4
votes
1answer
108 views

How does molecular collision excites the electron?

I have this question for a long time that in LASER when we do the pumping by heating how does molecular collision causes the atoms(molecules) to reach in excited state. E.g. in $\ce{He-Ne}$ laser when ...
0
votes
1answer
29 views

Find oxidation number of a metal in a compound

Calculate the oxidation number of $\ce{Fe}$ in $\ce{Fe2O3}$. Alright. So we have a metal and an non metal. This means that iron will lose electrons and give them to oxygen. So it will be a ...
3
votes
0answers
40 views

How can I tell if a molecule is polar or not? [duplicate]

Consider $$\ce{PCl3}\\ \ce{CH2Cl2}\\ \ce{HCN}\\ \ce{SiO2}$$ Which ones are polar substances? I appear to be lacking on the concept of "polar substance". I was just studying about Lewis ...
5
votes
1answer
123 views

Can molten sugar also rotate polarized light as sugar water does?

It is well know that the sugar water can rotate the plane of linearly polarized light, so light bends when travelling in sugar water. However, do the liquid state of sugar but not the sugar solution ...
10
votes
1answer
110 views

Singlet/triplet oxygen cycloadditions

Why can singlet oxygen participate in cycloaddition reactions while the triplet oxygen, on the other hand, can't?
3
votes
1answer
39 views

Empirical and molecular formula

I was doing a homework assignment and I got the following question wrong because I was supposed to multiply the empirical formula by 3 to get the molecular formula of $\ce{C6H10S2O}$. I put ...
4
votes
0answers
47 views

Reaction of Silicon monoxide with alcohols

Elements from the carbon group tend to form compounds with two oxygen's. Let's say I want to produce $\ce{SiO_2}$ out of $\ce{SiO}$ by mixing it with some alcohol, for example: $$\ce{SiO + ...
6
votes
1answer
130 views

Only-C chain molecules

Are (cyclic) $\ce{C}$-chain molecules as in the picture likely to occur or do they exist at all? and so on... EDIT: I'm considering only double bonds between $\ce{C}$ atoms. This rules out most ...
1
vote
0answers
39 views

Why are H2O asymmetric while CO2 is not? [duplicate]

What is the reason for water molecules $\ce{H_2O}$ being asymmetric while other molecules like $\ce{CO_2}$ being completely symmetric? See the pictures below: In both case there is an ...
3
votes
2answers
94 views

Are all molecular structures symmetric?

Are all molecular structure symmetric either in relation to a plane within itself or in relation to other molecules? Are there any completely asymmetrical structures when looking at molecular ...
1
vote
0answers
34 views

Method of representing molecules as 3d objects with surfaces [closed]

I need a way of representing molecules in 3d form. I wish to be able to define a 3d surface for simple organic molecules. Can anyone advise me on this? Are there any approaches, or solutions to this ...
6
votes
1answer
364 views

Which relatively simple molecules violate the octet rule?

I'm learning how to draw Lewis diagrams. Everything I've read emphasizes the octet rule. However, to the best of my knowledge, that rule only applies to elements in the first three periods. On our ...
1
vote
1answer
42 views

Which one of the following has less probability to create multiple bonds : N, P, C, S, Al, Ba? [closed]

Which one of the following has less probability to create multiple bonds? Phosphorus , Nitrogen, Aluminum, Sulfur, Carbon, Barium How can I know that from the Periodic Table? is there a certain ...
1
vote
0answers
31 views

Sugar dissolution test

Is there a way to detect whether sugar is completely dissolved in a cup of water other than looking at the bottom of the cup? I was wondering if there is a test or something that can be carried out ...
7
votes
1answer
77 views

What does the 129Xe NMR spectrum of XeOF4 look like?

What will the $\ce{^129Xe}$ NMR spectrum of $\ce{XeOF4}$ look like? I know that its electron pair geometry is octahedral, and the molecular pair geometry is square pyramidal. I believe that the ...
3
votes
2answers
103 views

Are these 3 molecular structures of ammonium bicarbonate the same?

Are these 3 molecular structures of ammonium bicarbonate the same? A: B: C:
1
vote
0answers
46 views

Molecules from atoms [closed]

Why do two oxygen atoms combine to form a molecule and not 3 or 4? Also, why does one sodium and one chlorine atom combine to form $\ce{NaCl}$ while two chlorine atoms are required to combine with one ...
2
votes
1answer
35 views

Calculating the number of molecules remaining

This is the question in my text book: From $392\:\mathrm{mg}$ of $\ce{H2SO4}$, $1.204 \times 10^{21}$ molecules are removed. How many moles of $\ce{H2SO4}$ are left? What I tried doing: First I ...
6
votes
4answers
1k views

Why is CF4 non-polar and CHF3 polar?

This question is a bit tricky to me because of the following: Take in consideration these two molecules: $\ce{CHF3}$ and $\ce{CF4}$ These are their Lewis dot structure: $\ce{CHF3}$ $\ce{CF4}$ ...
9
votes
2answers
322 views

How long do the bonds in a molecule hold under nominally stable conditions?

Disclaimer: I am not a chemist I was just drinking my Ice Age mineral water which is 'untouched since the Ice Age' and wondered if the bonds formed in each molecule have remained intact for all those ...
7
votes
1answer
560 views

Really how rare are hydrogen atoms?

Hasok Chang, a chemist, but perhaps more a philosopher recently published the book Is Water H2O? . Chang used the question and an extensive web of arguments ultimately as a platform to support a ...
3
votes
1answer
58 views

What causes “stringy” melted cheese (and similar behavior in other materials)?

I was wondering about this. What is the physics underlying the "stringy" consistency of melted cheese? That is, when the melted cheese is hot, and it is pulled apart, it forms strings of cheese. This ...
1
vote
1answer
67 views

Equivalent hydrogens in 2,3-dimethylbutane

So while calculating for the relative yield of monochlorination for 2,3-dimethylbutane, I was counting the primary hydrogens, I counted 6, but in fact it was 12. Why is it 12? How do you find ...
2
votes
1answer
43 views

MO for $N_2^{2-}$

Could someone please show me the MO diagram for $\ce{N_2^{2-}}$? What I did was since N has 5 valence $\ce{e^{-}}$, then $\ce{N_2}$ must have 10, and $\ce{N_2^{2-}}$ must have 12. And $\ce{N}$ has $s$ ...
1
vote
0answers
17 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 ...
6
votes
2answers
52 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
votes
1answer
126 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
votes
2answers
99 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 ...
9
votes
3answers
380 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 ...
1
vote
0answers
165 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
votes
1answer
36 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 ...
0
votes
0answers
45 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
vote
0answers
16 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
vote
1answer
121 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 ...
3
votes
1answer
25 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
votes
2answers
40 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
50 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
174 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
vote
1answer
42 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
114 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
85 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)?
11
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 ...
-1
votes
2answers
89 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 ...