# All Questions

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### Do only metals form ions?

This may be a very dumb question, but do nonmetals form ions? I am asking this because I was reading something and I came across the phrase "metal ions," which left me to wonder whether or not there ...
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### What materials are used to thermally imprint graphics on cotton fabrics?

For example t-shirt shops transfer color masks onto the cotton fabric using a thermal press. What materials are those masks made of?
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### Formalin fallen out of solution

Is there a way to bring back into solution a bottle of formalin that has crystallized? The bottle has been stored for several years at room temperature. Thanks in advance.
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### Mixing 1 cubic meter of HCl and NaOH: Temperature rise of a metal container?

Say I (perfectly) mix 1 $m^3$ of 1 M $\ce{HCl}$ with 1 $m^3$ of 1M $\ce{NaOH}$ at standard air pressure and room temperature within a metal vessel. Heat of neutralization for strong acids and bases is ...
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### Why water spills on our shirt change its colour?

While drinking water, some of it fell on my shirt and as usual, as has happened to many of us, the colour darkens? So why does this happen ? Is it due to some chemical effect or physical one ?
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### When do one have to actually calculate the net charge of an amino acid?

When the pH and the pKa levels differ by 2 or more you don't need to calculate the net charge. What you do then is to just count the negative and positive charge and add them up. When pH=pKa you also ...
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### Solubility of Gold in low concentrations

When preparing ICP-MS calibration standards for trace metal (~100 ppt) analysis, the values for Gold do not remain stable for more than a day. The standards are prepared using commercially available ...
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### Why does phosphorous give a free electron in silicon doping?

Extrinsic semiconductors are created by doping an intrinsic semiconductor; typically silicon is doped with phosphorous to create free electrons or boron to create "holes". In the case of phosphorous ...
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### What angle limits should apply to Graham condensers?

I have seen Graham condensers set at an angle (perhaps as low as 30 degrees from horizontal). I guessed this wouldn't be a problem because siphoning would clear the condensate. But I recently saw an ...
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### Which are the appropriate washing solvents for gas chromatography equipment?

I work in a laboratory where gas chromatography is used extensively. We handle terpenes and terpenoids (alcohols, ketones, and acetates derived from terpenes), organic solvents (acetone, acetonitrile, ...
376 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: $\ce{H-O-O-O-O-O-O-O-O-O-... -O-O-O-O-O-H}$
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### The solubility of salt A in water 40 g/l at 25 °C [on hold]

10 g of salt A are dissolved in water to form 500 ml solution x at 25 °C. Find the concentration of the resulting solution x
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### Mass percentage of KClO3 in decomposition reaction

When heated, a 3.40 g sample mixture of $\ce{KClO3}$ decomposes and produces 685 cm$^3$ $\ce{O2}$ gas at 30 $^{\circ}\mathrm{C}$ and 101 kPa. What is the mass percentage of $\ce{KClO3}$ in the ...
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### charge on nascent atoms

What is the charge on nascent atoms? Like [H] or [O] I initially thought that they were like free-radicals, without any charge but having unpaired electrons instead. I asked my teacher, who said that ...
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### How do I prepare the following solution I found in a research paper?(Details given below)

So I came across this research paper to synthesize nanoparticles and I want to replicate the experiment they did.Here is their experimental procedure(in their words) : 1.FeCl2·4H2O and FeCl3·6H2O ...
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### Name the following coordination complex

What are the IUPAC rules when naming a coordination complex like: $$\ce{[Pt(NH3)4][Pt(NH3)Cl3]}$$ Now according to my textbook, it is named as tetraammineplatinum(II) ...
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### What advantages does the mole have over counting large numbers using SI prefixes?

I'm trying to understand why chemists use the mole unit instead of just counting and using SI prfixes to simplify the big numbers with units such as zetta- or yotta-molecules (yotta=10^24). Here's ...
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### p-orbital versus s-orbital energies in hydrogenic atoms [duplicate]

In hydrogenic atoms, how can it be that the s-orbitals have the same energy as the p-orbitals (provided they have the same principle quantum number of course), even though on average the electron is ...
114 views

### How to calculate the pH of low concentration Hydrochloric acid in water

For relatively high concentrations of $\ce{HCl}$, I usually just assume that $\ce{[H+] = [HCl]}$, because $\ce{HCl}$ is a strong acid and completely ionizes. By taking the negative log of the ...
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### Solubility rate vs temperature as a percentage [on hold]

I am doing an experiment on the solubility rate vs temperature. I have recorded the time it has taken for certain substances to dissolve. How do I work out the solubility rate as a percentage?
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### Zirconium enolates stereoselective addition to carbonyls

Why do zirconium enolates almost always afford syn aldol products stereo-selectively with other carbonyl compounds?
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### Regioselectivity for electrophilic aromatic substitution with multiple strongly electron withdrawing groups

At which position will electrophilic substitution on p-cyanonitrobenzene occur? As both are -M groups, there are two possible sites of reaction, meta to each of the groups. The answer is meta to ...
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### Calculation of the lowest energy conformation with a webbased solution or freeware

I like to draw a molecule in different conformations in a) website or b) freeware and Calculate its relative energy difference (for example to the lowest global energy conformation) Display the ...
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### Does plastic packaging affect the food in them and if so how? [on hold]

Does plastic packaging of food have effects on them, how do they do?
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### With respect to colloid chemistry explain why sky is red in the morning and evening and blue at noon

Can colloid chemistry explain the phenomena behind why sky is red in the morning and evening but blue around noon?
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### Is atom other than hydrogen form bond similar to hydrogen bond?

For instance, is there any "lithium bond"? If not, why other atoms don't form such type of bonding?
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### Can we have Aromatic rings in a non-aromatic structure

Is it possible to have aromatic rings inside a structure that itself is non-aromatic? Is there an example.
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### Why is this named incorrectly?

In my Ap chem class I got this sheet with the names of a bunch of common polyatomic ions. One of them is named monohydrogen phosphate ($\ce{HPO4^2-}$). In naming, I learned not to use ‘mono-’ if it’s ...
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### At what point does Avagadros 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 ...
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### How much does a light heat the air around it?

My dad told me to turn off the lights when I'm not using them because it will keep the house cooler. I don't think he is correct that a light can heat up the room. How much of a difference in the ...
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### Combustion without hydrogen

Is there any fuels without hydrogen that will combust. My friend believes there might be and do to my experience I have never heard of one. Please explain and if u can show a balanced equation of this ...
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, ...
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### Program to covert WFN-file to Molden

I have tried google but without success so here the question: does anybody know a tool that can covert WFN-file to Molden or to Molpro format (including orbital info not the coordinates only).
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### How do things “glow in the dark”?

The only explanation that I can come up with for what makes things "glow in the dark" is that there is probably a chemical reaction slowly releasing the light that was previously absorbed. Am I ...
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### The conversion of energy during electroplating

I've made a test and i've faced a problem with a part of a question which says: "What is the conversion of energy occuring in electroplating? " I answered that it is conversion from electric energy to ...
22 views

### Can rocket candy explode during the preparation?

I would like to follow the steps in this video: https://www.youtube.com/watch?v=hyPysthIRss After I mixed the Potassium nitrate KNO3 and the ...
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### What type of hybridization does phosphorus have in P2O5?

I'm inclined to think that P has a $dsp$ hybridization in that compound, because it makes 5 bonds and 2 of them are $\pi$ bonds - with oxygen. However, I found in some websites that it may have $sp^2$ ...
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### Cooking with vinegar and lemon juice (Carpaccio)

I know the Maillard reaction to cook at 140-160 C. I know the low temperature cooking reaction to cook at 70 C. But which is the reaction that allow us cooking meat or fish with vinegar or lemon ...
116 views

### Work Done Upon Molecules

In which of the following processes is energy transferred into the substance by work ($w > 0$)? a) Expansion of a gas against the surroundings b) Expansion of a gas into a vacuum c) Vaporization ...
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### Ambidentate ligands

What are the eligibility criteria for ligand to be ambidentate? Is the size of cation and anion or hard and soft acids are only conditions for ligand to be ambidentate?
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### How do scientists count the exact number of electrons, protons, neutrons in the atom?

An atom is very small so it is probably difficult to focus exactly on a single atom. I wonder how scientists count the exact number of electrons, protons, neutrons in an atom of a certain element. ...
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### What is a food-safe level of exposure of plastic containers to heat?

There are many articles about how heat can trigger the release of potentially harmful carcinogens from plastic containers into the food or liquid they contain. Specifics they fail to mention, though, ...
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### Steps in mechanism of pyruvate dehydrogenase

I am having some trouble with certain steps in the above mechanism (from Proteopedia) detailing the mechanism of action of pyruvate dehydrogenase converting pyruvate to acetyl-CoA. In the first ...
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### How can I measure the amount of CO2 in grams in a known volume of soda based on its weight?

We have a soda machine that can fill either still water or soda. In both cases the amount is 400 ml in the beaker, but the soda weighs a little less. How can we use the volume X = 400 ml and the ...
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### Do more double bonds cause a bigger number of stereoisomers in cycloalkenes?

If trans double bonds cause cycloalkenes to be chiral, does a second trans or maybe cis double bond induce another chiral plane and hence four stereoisomer are possible for the given cyclodiene? The ...
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### Are all higher cycloalkenes chiral?

Are all higher trans-cycloalkenes chiral as trans-cyclooctene is? This question supplements my previous question: Why is trans-cyclooctene chiral? See also the follow-on question: Do more double ...
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### Percent concentration of 500 μM of H2O2

What is the percent concentration of hydrogen peroxide which has a molar mass of $500~\mu\mathrm{M}$? Is $500~\mu\mathrm{M}$ $\ce{H2O2}$ toxic to the eyes? A particular honey has a concentration of ...
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### Separate hydrogen in gas phase chromatography using helium as carrier gas [on hold]

Why isn't helium used as carrier gas to separate hydrogen in gas chromatography? My search so far didn't yield a reasonable result, but maybe you have an idea.
The p block elements generally have the general valence she'll configuration as $$n\mathrm{p}^{1-6}\,n\mathrm{s}^{1-2}.$$ Expected electronic configuration for palladium is \ce{^46Pd} = ...