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712 views

Benzalkonium chloride breakdown time

I wonder if and how long (approximately) it will take for benzalkonium chloride (shown above; $n = 8, 10, 12, 14, 16, 18$) to breakdown (degrade fully or partly) in a closed water loop with continuous ...
2
votes
0answers
63 views

Is it possible to observe ATP energy transport in table experiment?

Is it possible to take AMP or ADP, then phosphorylate it convert to ATP to charge with energy, then transport to other place an then observe energy freeing? In table / home / school experiment?
3
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2answers
157 views

How do non-sublimable solids exist in equilibrium with vapour?

How do non-sublimable solids exist in equilibrium with vapour? All substances exist in equilibrium with their vapour, something I learned from Jan's comment. But my question is how does that happen ...
4
votes
2answers
663 views

Can a system of 2 consecutive biphenyl systems be optically active , even if any adjacent biphenyl systems aren't optically active?

This question came in an online test, where they asked whether or not 22,26-dibromo-12,32-dichloro-23,25-diiodo-16,36-dimethyl-11,21:24,31-terphenyl was optically active. The answer is that, it is ...
8
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1answer
4k views

What is an active centre of a catalyst?

I was studying catalytic poisoning and read that in temporary poisoning, the poisoners are held at active centres by weak forces. What is an 'active centre' in this context?
2
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2answers
374 views

Is there safe chemicals for making voice pitch or bass?

I'm looking for safe experiment that can pitch and bass my voice.finally I find a video that do it but he said "not try in home,ok..?".Is there safe tool or chemicals for Manipulation of the larynx is ...
-3
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1answer
67 views

Water side-reactions in organic electrochemistry (redux) [closed]

(note: this is a reposting of part of my original post which I was told had too many questions in one post) Please bear with me as I am a chemistry newbie, but I am autistic and have recently ...
0
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0answers
2k views

Why are aqueous solutions included in the equillibrium constant but liquids are not? [duplicate]

I understand solids are insoluble and will just sit at the bottom of the vessel so we don't include them. But I am confused as to why aqueous solutions are used in the equilibrium equation but ...
0
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2answers
80 views

What are the order of the reaction under the following conditions?

The experimental rate of a reaction $$\ce{A + 2B -> C + D}$$ $$\frac{\mathrm dx}{\mathrm dt} = K[\ce{A}][\ce{B}]^2$$ Calculate the order of the reaction when (i) $[\ce{A}]\gg[\ce{B}]$ (ii) $[\ce{B}...
4
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1answer
694 views

Aqua Regia Coloring

I was working with Aqua Regia in the lab today and was impressed by how quickly the solution (HCl and HNO3) changed colors from a colorless liquid to orange to a deep red. I didn't time it, but I ...
5
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1answer
2k views

Trans-hydrogenation of alkenes

Both this and that question seem to indicate that the hydrogenation of alkenes to alkanes or alkynes to alkenes is always a syn process. However since hydrogenation is not a concerted process, I do ...
2
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2answers
11k views

Why is the boiling point of a solution higher than that of a pure solvent? [duplicate]

Why is the boiling point of a solution higher than that of a pure solvent? I think when a non-volatile solid solute is added to a solvent, some of the liquid solvent molecules are replaced by solute ...
4
votes
2answers
2k views

What happens when you mix milk and coke?

Add small amounts of milk to a bottle of coke, and you end up with a white-ish precipitate with a clear liquid on top. "The Internet" seems to agree that phosphoric acid in coke reacts with something ...
2
votes
1answer
4k views

Ferric Chloride solution weight

When I notice that ferric chloride is sold as $40\%$ solution w/v, does it mean weight / volume? Is it a matter of for example adding $40$g of ferric chloride crystals to a water solution where the ...
3
votes
1answer
260 views

Does boiling water alter the chemical properties of dishwashing liquid?

An ex-housemate of mine claimed to be a former chemist, and once told me not to use boiling water (or recently boiled water) when leaving dishes to soak, as the temperature would chemically alter the ...
5
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1answer
150 views

Carbocation Rearrangement - Till which neighbouring carbon is it possible?

In the above reaction, clearly the OH will be protonated followed H2O leaving, seeing that it's a good leaving group. Now there can be two possibilities either a alkene is formed as is, or the ...
1
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1answer
740 views

Claisen Condensation vs. Trans-Esterification

In the Claisen condensation, an alkoxide $\ce{RO-}$ acts as a base. However, in trans-esterification, an alkoxide $\ce{R'O-}$ attacks the carbonyl carbon of an ester as a nucleophile. Is this because ...
6
votes
1answer
244 views

Is isobutanol miscible with ethanol?

I can only find info on sec-butanol (aka butan-2-ol) and ethanol. I need to know whether isobutanol forms an azeotrope with ethanol. Can you direct me to a legitimate info source too, please?
1
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1answer
78 views

Volume increase when air is enriched with water

When air is enriched with water, how much volume increase can be expected? I am aware that the volume increase will not be proportional (i.e. $\pu{1L}$ air + $\pu{10mL}$ gasified water will result in ...
3
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1answer
1k views

How to generate fully coloured electrostatic potential maps in Avogadro?

I want to generate electrostatic potential maps of molecules using Avogadro, that show the colour scheme ranging from blue through green and yellow to red. In this Youtube video, at 1:32, the video ...
0
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2answers
117 views

Should you work in metres-cubed or litres in chemistry? [closed]

Generally, is it better to work in metres-cubed or litres in chemistry? My undergraduate degree was in civil engineering and we always worked in $\mathrm{m^3}$. However, I notice the gas constant $R$...
4
votes
1answer
2k views

Barium sulfide vs Ba2S2

I was predicting a very simple chemical equation $$\ce{Ba + S ->}$$ And I had solved it as $$\ce{Ba + S -> BaS}$$ The answer should make sense as barium has a charge of +2, and sulfide has a ...
3
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2answers
3k views

How can alkali metals form covalent bonds?

Alkali metals have spherical outer s orbitals unlike elements like carbon which have protruding p orbitals that can "attach" onto other orbitals to form covalent compounds. Even in cases like methane ...
1
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1answer
60 views

Water contamination of Polyol F0350 [closed]

I just got asked this question on an interview: I transported Polyol F0350 in 3 tanks. Upon arrival one tank was determined to have an unacceptable water content. It may have been contaminated with ...
3
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1answer
2k views

How to measure ppm of copper

What is the best way to measure ppm of copper in colloidal solution. My TDS meter only shows at 2ppm which cannot be correct.
0
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1answer
71 views

What is the mathematical reason behind the gradual increase in osmotic pressure?

Question: Arrange the following in increasing order of osmotic pressure, $0.1~\mathrm{M}$ cane sugar, $0.1~\mathrm{M}$ $\ce{NaCl}$ solution, $0.1~\mathrm{M}$ $\ce{H2SO4}$. Solution: As the number ...
0
votes
1answer
587 views

Why does Raoult's law work? [duplicate]

I am trying to look for the entropy explanation but I do not understand anything I can find. Please keep it simple but talk about it from a entropy point of view. Use water and a volatile solute as an ...
1
vote
1answer
178 views

Why does the composition of Ocean Water list sodium and chloride separately?

This is the site I am using. It is also found here, but this uses mg/L instead of percents. It lists Sodium at 30.8%, and Chloride at 55.3%. How can this be? Shouldn't the two be listed as Sodium ...
2
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1answer
762 views

Oxidizing and reducing agent

What i know about the above question is that a compound acts as an oxidising as well as reducing agent when the oxidation of central metal is somewhere between it's maximum and minimum oxidation state ...
0
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1answer
85 views

Excitation of an electron of H-atom from n=2 to any $n_2 $

I got taught that if an electron de-excites from any $n_2 $(where $n_2 >3$) to $n=2$, the energy change can be represented by $$\Delta E=13.6\left(\frac{1}{n_1^2}-\frac{1}{n_2^2}\right)\ \mathrm{...
7
votes
1answer
122 views

Achiral universe - asymmetric synthesis

Would it be somehow possible to conduct asymmetric synthesis if all chiral molecules would exist only as racemates in nature?
0
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1answer
484 views

Basic strength of compunds [duplicate]

Why is Ammonia stronger than Phosphine in terms of basic strength? I am confused as Nitrogen is more electronegative than Phosphorous.
3
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3answers
2k views

Is the rate of desorption dependent on pressure?

While I was learning about Langmuir's adsorption isotherm in my chemistry class, my teacher talked about the situation when the rate of adsorption and desorption will become equal. However, he ...
1
vote
1answer
551 views

Would Schweizer's reagent dissolve nitrocellulose?

Schweizer's reagent, or tetraamminediaquacopper dihydroxide, is used in the production of rayon. It does this by dissolving the cellulose which can be acidified to form strands of cellulose. I have ...
2
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0answers
154 views

How to detect dog feces?

I am working on building a robot to detect and pickup dog poop. I have looked at the concentrations of the various components and simple chemical/electrical ways to detect them. The best component ...
4
votes
1answer
477 views

Clarification about Frost diagram y-axis conventions?

I was looking at the Frost diagram of Manganese, and on the UC Davis ChemWiki, I see this one: However, the one straight from my textbook, "Descriptive Inorganic Chemistry" (Overton), looks like this:...
7
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3answers
222 views

Can atoms delocalize in molecules?

Electrons can delocalize over multiple equally probable bonding structures. Can atoms delocalize over multiple equally probably bonding structures in certain cases? It seems to me that any such ...
0
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1answer
2k views

Alkali metal hydrides

I know that stability of alkali metal hydrides decreases down the group,Hence the lowest member in the group easily breaks into its cation but does this easiness of breaking into cation has any ...
7
votes
1answer
1k views

Software for visualization of 3D models of chemical structures with atomic orbitals

A number of programs are available that let you build, visualize, and analyze 3D models of chemical structures (I use Chem3D/ChemBio3D). Current versions usually include various possibilities for the ...
2
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0answers
1k views

Variation in pressure for a gas phase reaction

Predict how the total pressure varies during the gas-phase reaction $\ce{N_2}(g)+ 3 \ce{H2}(g) \rightarrow 2 \ce{NH3} (g) $ in a constant volume container. Reference: Atkin's Physical Chemistry, ...
0
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1answer
364 views

Preparation of a fluoride solution using CaF2

I need to prepare several solutions with different concentrations of $\ce{F-}$, in order to carry out some investigations on fluoridated water. Would this be achievable by dissolving calcium fluoride, ...
4
votes
1answer
415 views

Decomposition products of magnesium ethanoate

What does magnesium ethanoate decompose to? The Wikipedia page states that one of the products is magnesium oxide. What's the other product? I can come up with some guesses: Ethanoic anhydride ($\ce{...
1
vote
1answer
3k views

Net conductivity of mixtures

If we have a solution, of conductivity k1, and another solution of same volume having conductivity k2, then what will be the conductivity if I mix the 2? I think that net conductance should be the sum ...
3
votes
1answer
2k views

Toothpaste and water

I noticed when brushing my teeth that toothpaste causes water to spread away from it. If you put a bit of toothpaste water mixture on your finger and touch it to a wet sink you will see the water on ...
1
vote
1answer
1k views

Which elements exhibit allotropy?

I was just reading this article about allotropes which relates allotropy with some specific elements and also this wiki article. Also some other articles some of which relate allotropy with catenation ...
8
votes
2answers
18k views

Why does rotating a double bond break the bond?

It is well known that double bonds are "stiff" and make particles less likely to rotate around the bond. But why? What makes it so that the bond has to be orientated a specific way?
1
vote
1answer
41 views

What guarantees that there is a thermodynamic equilibrium in a closed chemical reaction network independently of the mass-action kinetics? [closed]

I would like to know according to which we can state that there is a unique equilibrium of a closed chemical reaction network (at constant circumstances) without supposing mass-action kinetics if time ...
2
votes
1answer
1k views

Melting point of ocean salt: eutectic?

I'm interested in the melting point of ocean salt. While sodium chloride has a melting point of 801 °C, ocean salt contains 15 % other ions, mainly sulphate, magnesium, calcium and potassium (the ...
3
votes
3answers
7k views

Reaction between phosphorus pentachloride and sulfuric acid?

I am a novice in chemistry. While reading a magazine, I stumbled on some information about phosphorus pentachloride and sulfuric acid. Phosphorous pentachloride and sulfuric acid are both good ...
-1
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1answer
195 views

Orange dust floating ontop of Electrolysis solution [closed]

While I was doing an Electrolysis experiment with stain less Anode/Cathodes on aluminium plate, Orange dust started floating on top of the water solution. What is this chemical's name and is it toxic ...

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