# All Questions

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### Making Lyophilized Cake Lookalike using household ingredients

I'm working on a machine learning model to identify flaws in vaccines in lyophilized cake form. To train the model, I need a number of samples that look something like this: I have vials, but I'm ...
7 views

### styrene confusion

I am studying NMR and while looking at styrene, I can't figure out why the two hydrogens on the terminal double bond are not equivalent. Is it because one is closer to the ring in position than the ...
11 views

### What will be produced when sucrose and potassium bitartrate react with each other?

What would happen if sugar and cream of tartar react with each other? Would it create an ester? $$\ce{KC4H5O6 + C12H22O11 -> KC16H21O14 + 3H2O}$$ Is this correct? If not, why?
8 views

### Is there a molecule in which the central atom makes 8 bonds and has an hybridization of sp3d? [on hold]

Doesnt matter what the molecule is, but the central atom has to be sp3d and make 8 bonds
12 views

### What reactions involving hydrazine with dinitrogen tetroxide and possibly a contaminant could produce a salt?

Hydrazine $\ce{N2H4}$ and dinitrogen tetroxide $\ce{N2O4}$ form a hypergolic fuel and oxidizer pair widely used in spacecraft including Akatsuki. Wikipedia states: Hydrazine can be monoprotonated ...
6 views

### When is the concentration in which you put into the equilibrium constant equal to 1 for solids and liquids?

There are many websites which states that pure liquids and solids have a concentration equal to one, but for some equations they are not! How do you explain the difference for this equation? For the ...
26 views

### Thermal decomposition of K2CO3

K2CO3 doesn't boil - it thermally decomposes at 1200c. However, I find conflicting information online about this. Roughly what I have found say three inconsistent things. (1) It doesn't decompose (...
8 views

### What is the product : Reaction of 2,2-dibromopropane with alcoholic KOH [on hold]

What will be the product : Reaction of 2,2-dibromopropane with alcoholic KOH .
10 views

### Will distillation do the job of purifying the water?

I asked about my sophisticated water purification system for a generation ship on Worldbuilding Stack Exchange, and somebody mentioned this: If you're gonna go to all the trouble of distilling it, ...
9 views

### Predominating species in a solution

My question is When ferric oxide Fe2O3 is dissolved in 6M HNO3, which iron containing species predominates in solution?
16 views

### How to determine if a compound is a strong, weak, or non-electrolyte?

I'm stuck on questions asking whether a given chemical formula is a strong or weak electrolyte in an aqueous solution. I did some research online, but could not get a specific solution that I could ...
12 views

### Is it possible to make micelles to pick up Microplastics from water?

I'd like to know if I could get micelles to pick up microplastics in water. I read that microplastics are sometimes charged, so can we make the lyophobic end to pick up microplastics, so that they can ...
28 views

### Breast milk with reverse osmosis

I would like to make life lasting breast milk jewelry. I would need at least 5ml to make it. I've been doing a lot of research to get the best results, so far this questions are the result of more ...
6 views

### Boys-Bernardi counter poise calculation [on hold]

can someone tell me how to do a Boys-Bernardi counter poise calculation through the CPMD program. thank you.
27 views

### How high can compression be in a combustion engine? [on hold]

In order to make combustion engines more efficient by increasing compression I wonder how high compression can be in a combustion engine. Could solid combustibles, like gun powder and similar, be ...
27 views

### Bromination of an alkene in presence of water

Bromination of an alkene in presence of water results in its mechanism in a cyclic bromonium ion and "afterwards $\ce{H2O}$ binds to the carbon atom surrounded by more electron donating groups." This ...
13 views

### Can classification techniques used for identifying solids be used to identify precipitates?

I am preparing for an assessed practical experiment where an unknown precipitate must be identified. I know that precipitates are insoluble, and my textbook says they are considered to be solid with ...
24 views

### Hydrogen bonding in o-nitrophenol versus o-nitobenzoic acid

p-nitrophenol is more acidic than o-nitrophenol because of hydrogen bonding in the latter. If I apply the same logic, then o-nitrobenzoic acid should be less acidic than p-nitrobenzoic acid. However, ...
25 views

### Determinig the mass of a third isotope [EASY] [on hold]

I am totally new to Chemistry. I am taking my first Physical Chemistry course. And in the exercise sheet i am solving there is the following question : There are three Oxygen isotopes, occuring with ...
21 views

### Do glass and plastics NATURALLY crystallise at STP? [on hold]

Diamond, being a higher energy state, convert very slowly to graphite, which is stable at STP. Similarly, do glasses (tempered glass, glasses in lenses etc.) and plastics which are amorphous become ...
17 views

### Free aldol addition and condensation [on hold]

Just had some questions I'm working on that I'd like some help with; what is the mechanism with arrows for the base-catalysed aldol addition and condensation of ethanal with itself (with both steps). ...
17 views

### Is there a heatformed vinyl-like plastic that is hard as shellac when cold?

I recently started collecting shellac records, and got the idea of releasing my own music on 78rpm shellacs. But the exact formulas and techniques for making shellac records seems pretty much lost to ...
36 views

### Bohr's postulate of quantisation of angular momentum

The Bohr's postulate of quantisation of angular momentum can be written in a formula as $mvr = nh/(2π)$ where $m$ is mass of electron $v$ is its velocity $r$ is the radius of that shell $h$ is ...
15 views

### NaOH in povidone iodine?

I just bought povidone iodine to clean my face (it helps), and i bought a big pack which doctors use to clean skin too. But i noticed that it contains NaOH 45%, i dont know is it dangerous when used ...
577 views

### Strange Sticky Substance on Digital Camera

I purchased a used Canon Powershot A1100 IS camera online. When I received it in the mail it had a very strange sticky substance that looked like a thin film. It resisted attempts at cleaning. Water, ...
28 views

### Constant Pressure and Temperature during Phase Change

One of the solution guides to a question I was working on said that pressure and temperature is constant for a phase change. I understand why temperature is always constant for a phase change, but don'...
24 views

### Why is absorption spectrum of beta-carotene different from Zeaxanthin?

Here are the molecular structures of beta-carotene and zeaxanthin These molecules only differ in the OH groups and the conjugated backbone length is exactly the same. I read that the absorption ...
23 views

### Do formulas to find number of nodes applies to all degenerate orbitals?

total number of nodes $= n-1$ number of angular nodes $=l$ number of radial nodes $= n-l-1$ for example: for $\mathrm{4p}$ total nodes $= 4-1= 3$ no. of angular nodes $= l= 1$ radial nodes $= 2$ ...
12 views

### Connection between Gibs free enrgy and Solubility [on hold]

My text book says that despite the sign ,if the magnitude of the gibs free energy we calculated Increases ,the solubility will descrese.Can you please explain this?
44 views

### How could benzenehexol be reduced to benzene?

How could benzenehexol (hexahydroxybenzene) be reduced to benzene? Could an active metal like potassium remove the oxygen?
34 views

### Iodine exception [on hold]

The state of a substance depends on the intermolecular bonds between the molecules of the substance.The stronger the intermolecular bonds , the harder the substance becomes a gas. Iodine molecules ...
35 views

### Using molecular orbital for determining leaving group trend and nucleophilicity

Here is the question. Which one has better leaving group, cyclohexanol or cyclohexane that has $\ce{OH_{2}^{+}}$ substituent? Explain. I know the answer is the latter because if both compounds are ...
23 views

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### Minimize ozone generation while generating negative ions of air? [on hold]

Consumer air ionizers do this; I'm looking to build something larger, but I still need to keep ozone generation at the smallest minimum possible. What is the method? A precise voltage to the ...
24 views

### why is there a net current at halfwave potential?

Im wondering why there is a current measured at a halfwave potential? According to my understanding at the halfwave potential of a diffusion controlled reduction or oxiation at an electrode, there is ...
20 views

### What is the definition “Moist Chlorides” [on hold]

I am currently evaluating material suitability for a project. When looking at some suppliers technical data sheets there is a distinction of sea water, brackish water, and then there is sometimes a "...
16 views

### Sodium Chloride solution question [on hold]

What is the mass of sodium chloride used to create a 100 mL solution at a concentration of 1.5 M? Please provide any of the work done to solve the problem as well.
11 views

### Ionic Equilibria [on hold]

Grape juice has a pH of 3.75. Grape juice can be titrated with standard alkali. A 25.0 cm³ sample of grape juice was exactly neutralised by 27.5 cm³ of 0.100 mol dm^-3 sodium hydroxide using ...
21 views

### Which compound can be purified by forming a hot aqueous solution that recrystallises on cooling? [on hold]

A. Cyclohexene B. Ethanoic acid C. Phenylamine D. Benzoic acid I thought it was C but it’s wrong. What’s the correct answer and why?
1k views

### Will Proving or Disproving of any of the following have effects on Chemistry in general?

I am working on a project relating to- https://en.wikipedia.org/wiki/Millennium_Prize_Problems I wanted to list the effects of them being proved or disproved in different aspects of science and maths....
22 views

### Assigning Cahn-Ingold-Prelog priority numbering rules for 2 groups

I was asked to draw the perspective formula of $$\ce{(3R,4R)CH2=CH-CH(CH3)-CH(CH3)-CH2-CH3}$$ Then I had to assign priority between the two groups: $$\ce{-CH=CH2}$$ and \ce{-CH(CH3)-CH2-...
35 views

### Explaining the result of experiment---Aluminum foil heated in boiling KMnO4 solution

I've recently been thinking back to an impromptu "experiment" I performed almost exactly 3 years ago. The setup was as follows: A concentrated solution of KMnO$_4$ was produced by dissolving 2 ...
20 views

### What forms/allotrope Does most common steel/iron exist in? [on hold]

Sorry to ask such a seemingly basic question, but I cannot seem to find a site that lists allotrope, formulas, etc. of steel by how common they are.... I've read extensively (I think) about austenite,...
29 views

### Gas Composition Undergraduate Assignment Question [on hold]

I recently was given a homework problem relating to gas composition. The Gas in question is gas that is dried, so I asked my TA whether or not this included water. The TA said that the question does ...
16 views

### GSR (skin conductance) on leather [on hold]

In terms of GSR, skin conductance is used to measurfe and analyze differences in conductivity. However is it possible that leather (aka tanned and dead skin) has conductance values like living skin? I'...
25 views

### Gas Composition Undergraduate Question [on hold]

Given this question, how would you go about determining the composition? Natural gas before treatment consists of 40.0% methane, 15.0% ethane, 10.0%, carbon dioxide, 15.0% hydrogen sulfide ...
20 views

### IR vs Raman Activity from Character Table [on hold]

For the molecule trans-1,2-dichloroethene (point group $C_\mathrm{2h}$) determine using only the two C−Cl bond elongation vectors the symmetries of the possible C−Cl stretching modes. The $z$-axis is ...
18 views

### Show that the following processes are irreversible [on hold]

Show that the following processes are irreversible. (a) Gas freely expands from V to V+dV (dV>0) adiabatically, and (b) Gas expands adiabatically from p to p+dp (dp<0) via the Joule-Thompson ...
17 views

### How to dissolve PLA/PCL/PMMA?

I have a research about electrospun membrane synthesis where I dissolve PLA pellets in chloroform:methanol (3:1) for 3 hours and also PCL pellets in chloroform:methanol (3:1) for 3 hours too. Another ...

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