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7
votes
1answer
704 views

What is known about the phase of matter at very high temperature and enough pressure?

Are there theoretical reasons for or against the existence of materials that will not become solid at some fixed, sufficiently large temperature when enough pressure is applied? Or is this even the ...
1
vote
2answers
2k views

deduce chemical properties of a compound from elements

If we know the properties of two elements e.g Oxygen and Hydrogen. We know the following properties sound speed boiling point melting point refractive index etc. given that information, is it ...
6
votes
2answers
8k views

Is tin and tinware toxic?

I tried to find info on tin toxicity but there is not much. Wikipedia here says that it is not very poisonous; but there could be cases. My question is: is it dangerous to say have a coffee boiled ...
4
votes
1answer
2k views

Moment of inertia for a triatomic molecule

What does the moment of inertia for a molecule mean? How is it useful? Most importantly, how would I go about solving it for a triatomic molecule?
10
votes
1answer
939 views

Isolating salt from sea water using filters

Could a filter be used to isolate salt from sea water? Could we say that the water molecules are smaller than the molecules of salt dissolved in the water. I have no relation to chemistry or physics, ...
12
votes
2answers
13k views

Why are alcohols with longer chains less polar?

In my self-study, I recently came across the following question: "Choose the solute of each pair that would be more soluble in hexane ($\ce{C6H14}$). Explain your answer. (a) $\ce{CH3(CH2)10OH}$ or $...
0
votes
1answer
552 views

Product/(s) of the following reaction

I was wondering what the product will be in the following reaction: $$\ce{H3COOCH3 ->[\ce{H+}]} \:?$$ I was thinking about $\ce{CH3COOH}$ being a product but I do not know the mechanism.
3
votes
1answer
6k views

Reaction between potassium permanganate, alum, and sodium hydrogen sulfite

When I was a teenager, I played with a chemistry set. I tried adding potassium permanganate, alum, and sodium hydrogen sulphite (not sodium hydrogen sulphate) to water. Upon adding the third ...
1
vote
1answer
103 views

Methods: Does failing at intermolecular properties mean the same for intramolecular properties?

Let us consider the following: 1.) Method X fails at describing intermolecular non-covalent interactions. 2.) Method X excels at describing molecules of type Y. 3.) Method X ___?___ at describing ...
8
votes
1answer
173 views

Why would the loss of H₂ to space mean that the Earth's geochemistry would be based on acid/base reactions?

I am reading a paper[1] that contains the line: Most of the $\ce{H2}$ in the Earth's mantle escaped to space early in the Earth's history; consequently, the overwhelming majority of the abiotic ...
7
votes
2answers
34k views

Oxidation number for nitrogen in ammonium sulfate [duplicate]

I'm trying to find the oxidation number of $ \ce N$ in $ \ce{(NH4)2SO4}$. The answer is supposed to be $-3$ but I can't figure out the logic behind this.
10
votes
1answer
7k views

What is 'autogenous pressure'?

Compound 1 was hydrothermally synthesized under autogenous pressure[1] I've seen this term used a few times, but with no real explanation of what it means forthcoming. I suspect it refers to the ...
17
votes
5answers
28k views

What is the chemical structure / hybridization of sulfuric acid?

I was looking at the chemical structure of $\ce{H2SO4}$. Intuitively, I would have expected this molecule to be square planar in accordance with $p^2d^2$ or $sp^2d$ hybridization, but instead it is ...
7
votes
3answers
2k views

Why does cesium have a positive electron affinity?

When an electron is added to cesium, why is energy released?
5
votes
1answer
198 views

Modeling perturbations of a quantum mechanical system

I'm wondering how to properly perturb a quantum mechanical system. I'm looking for a way to express the return to equilibrium of such a perturbed state, where the perturbation is in the Hamiltonian. ...
8
votes
1answer
1k views

Very slow chemical clock reaction

I'd like to preface this with a declaration of my understanding that this is not necessarily possible. I was wondering if anyone knew of a chemical clock reaction where the period before the first ...
16
votes
3answers
4k views

Modern alternatives to Gaussian [closed]

Specifically, I'm curious if there are any programs which come close to Gaussian in breadth but also take advantage of things such as GPU processing. There's a page on wikipedia that goes through ...
2
votes
0answers
284 views

Spectral analysis of periodic table of elements in time domain

I'm trying to get the spectral analysis data of the periodic table of elements in the time domain format or find a site that has the data in the time domain format. All the sites I know have the data ...
20
votes
2answers
2k views

Is there a simple way to get the circular dichroism of a molecule from its structure?

Are there any heuristics to get the relative absorbtion of left and right circularly polarized light by a molecule from its molecular structure? Is it even possible to predict which polarization is ...
6
votes
1answer
101 views

What legal guidelines exist for completeness of a Materials Safety Data Sheet?

I know that the answer to this question will vary by country, but some aspects must be similar amongst those countries that have authorities overseeing chemical and industrial hygiene. The Wikipedia ...
3
votes
1answer
9k views

Can acidic conditions break disulfide bonds

I am denaturing a protein using organic solvent and acid (49:49:2% water:methanol:acetic acid), but I want to maintain the disulfide bonds. My chemistry knowledge isn't good but disulfides are broken ...
2
votes
1answer
1k views

Why don't atoms with expanded valence shells have a formal charge?

I'm working through Chemistry - Principles and Practice, 3rd Edition and I have few complaints so I don't think it's the text. At one point, I was asked to draw the Lewis structure, with formal charge,...
16
votes
2answers
17k views

How to properly dispose of sodium…or store it properly

While performing an inventory of my school's chemical storage closet today, my fellow teacher and I found some sodium tucked away in the back corner of our flammables cabinet. One container appears ...
7
votes
3answers
3k views

Which of the following possesses the highest energy electron?

Which of the following possesses the highest energy electron? $\ce{Br-}$ $\ce{Ca^2+}$ $\ce{Cr+}$ $\ce{As}$ Don't bromine and arsenic have equally high energy electrons (i.e. in ...
5
votes
1answer
454 views

What does the reaction of chromium with ozone form?

I know almost nothing beyond 10th grade chemistry. I'm trying to name a web application, and was wondering what the products are of a reaction between the element Chromium and the gas Ozone (...
5
votes
1answer
692 views

How can I identify and neutralize the chemical leaching out of new nitrile gloves?

I have a few cases of brand-new, nitrile gloves of a type and vendor that used to be good. But apparently, the vendor has moved manufacturing to a different country and outsourced customer service to ...
10
votes
1answer
5k views

Interpreting a formula tattoo

I saw on the Internet and I'm curious as to what compound is represented by it.
15
votes
1answer
1k views

Does the chemical in an alkaline battery make battery leaks unavoidable?

Battery leaks was an issue in the 80s and 90s, and since quality and innovation is constantly improving, I thought battery leak might be slowly going away. But I found that even nowadays, name brand ...
8
votes
2answers
291 views

Is there a liquid crystal or similar material that gets cloudy when an electric field is applied, but is otherwise clear?

Is there a way to make a liquid, such as a liquid crystal material, transition from cloudy or clear and vice-versa using only electric current? By cloudy, I mean, similar to the effect that ...
12
votes
4answers
411 views

standard reference for thermodynamic properties?

I'm a non-chemist attempting to put together a chemistry paper. Up to now I've got my thermodynamic data from various random pdf files found on the web, together with Wikipedia. Now that the paper is ...
0
votes
1answer
371 views

Products of HMTD decomposition

Hexamethylene triperoxide diamine, "Hex" for short, is an explosive organic compound. I want to know the products of this reaction: $$\ce{C_6H_{12}N_2O_6 -> ? + Energy}$$
6
votes
1answer
10k views

Pipetting strong acid with plastic material

Can I pipette concentrated sulfuric acid using a plastic pipette tip? Will either the plastic or the acid be affected?
41
votes
1answer
4k views

Why is methane's molecular formula conventionally “CH₄”, while water is “H₂O” (among others)?

While revisiting some of my old notes about the Miller-Urey experiment, I stumbled across the "equation"... Electricity + $\ce{CH4~/~ NH3~/~H2O~/~CO}$ = Amino Acids This got me thinking. ...
6
votes
2answers
1k views

Comparison of acids to dissolve phosphates

I am currently reading this German paper on the dissolution of phosphates by acids and chelants. The authors do a "fast-test" of the dissolving power of different acids which goes as follows: For ...
3
votes
2answers
4k views

Polymer Slurry used in boring foundation holes?

I watched a video on the construction of Burj Khalifa, Dubai. The construction engineers answered that they're using a special type of protection known as Cathodic protection to protect from the ...
4
votes
1answer
756 views

How to compute the residence time for given flow rate in standard cubic meters?

I'm given a flow rate of a gas mixture of $3\ \mathrm{Nm^3/h}$ in standard cubic meters through a cylinder of length $50\ \mathrm{cm}$ and cross section $70\ \mathrm{cm^2}$, can I compute how long a ...
7
votes
2answers
2k views

What chemicals could absorb/adsorb ambient atmospheric methane?

From an article in the New Scientist in 2010, Since pre-industrial times, methane levels in the atmosphere have risen from around 715 parts per billion to nearly 1800 ppb, claims Folberth. "If ...
5
votes
2answers
1k views

Good acid for cleaning marine toilets

Problem: On my boat I have a marine toilet. It is operated with salt water. The problem is, on the interior of the outflow tubing it accumulates some sort of hard grime. I am looking for a good way ...
3
votes
1answer
4k views

Bisulfate vs Hydrogen sulfate

What's the difference between bisulfate and "something" hydrogen sulfate? Has there historically been a preference for one over the other?
1
vote
2answers
2k views

Iron nomenclature differences between Iron(III) and Ferric [closed]

As I was doing my Ap Chem homework, sometimes the question would use Iron(III) and sometimes it would use Ferric. What's the difference in usage? Also, what's the difference between Iron(II) and ...
5
votes
1answer
2k views

How to determine stable electron states in ionic and covalent bonds?

I'm working on a program that needs to determine if a bond between two or more elements will result in a stable state. I understand at a high-level how to fill electron subshells using the Aufbau ...
2
votes
1answer
2k views

How to calculate entropy change for a gas reaction using $S^\circ$?

I'm calculating molar changes in thermodynamic properties due to reactions between gasses (assumed to be ideal gases). I can calculate $\Delta H$ easily enough, because it's just $\sum_i \nu_i\...
3
votes
1answer
1k views

What is the name of cyclopropane with a double bond?

I was drawing out all the isomers of $\ce{C5H8}$ and came upon two structures of cyclopropane attached with double bonds. The group is neither a methylene nor an ethyl... what is it? What are the ...
0
votes
1answer
3k views

Software for chemical reaction simulation [closed]

I wonder, what software packs / environments are available for chemical reaction simulation. The goal is to learn or just rehearse some basic knowledge in chemistry. I suppose there should be some to ...
4
votes
2answers
164 views

What is the energy package released to the outside world?

Consider a chemical reaction where two different particles form another one $$\ce{O + O_2 -> O_3}$$ I find it confusing how this can be an exothermic process. How to picture the release of $+\...
14
votes
1answer
5k views

Order of dipole moments

What is the order of dipole moments for $\ce{SO3, SiO2, P2O5,}$ and $\ce{Cl2O7}$? This question is from a book and the answer given is $\ce{Cl2O7 < SO3 < P2O5 < SiO2}$. Can someone explain ...
2
votes
1answer
2k views

Composition of a typical printed circuit board (PCB)?

For the purposes of x-ray absorption, I'm trying to discover the average chemical composition of a typical PCB. My research so far has indicated that the most common type of PCB is designated FR-4. ...
40
votes
6answers
72k views

How can carbon dioxide be converted into carbon and oxygen?

How can $\ce{CO2}$ be converted into carbon and oxygen? $$\ce{CO2 -> C + O2}$$ Alternatively: $$\ce{CO2 + ? -> C + O2}$$ I'm aware that plants are capable of transforming $\ce{CO2 + H2O}$ to ...
5
votes
1answer
3k views

What is burst nucleation? [closed]

Can you tell me what is a burst nucleation process, and how can it be used for synthesising uniform nanoparticles? Can you also provide (if possible) any links to papers or materials regarding ...
3
votes
3answers
33k views

Reaction of soap with water

I've seen it many times... Why does soap become foam-like when it reacts with water (moisture) or when we touch it with wet hands.. What compound actually causes this physical change? And why does ...

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