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5 views

suitable plasticizer for paraffin to improve bending properties

I am trying to develop a wax sheet consists of paraffin as raw material (because of low cost) and melting point between 55 to 60 degrees Celsius. because of the paraffin brittleness, I tried to add ...
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0answers
19 views

Safe exothermic reactions for winter survival situation

I don't have a ton of chemistry experience beyond my undergrad courses for my STEM major, but I have a question that regards some practical application. I'm from Austin and the winter storm reaped ...
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0answers
8 views

Photocatalyst bandgap

Can the Gibbs energy equation be used to calculate the band gap for a photocatalyst, or can it only be used to calculate the oxidation potential of water? I have been reading into photocatalytic water-...
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0answers
8 views

A question regarding CIP rule [closed]

Hi why is the absolute stereochemistry of the carbon in the 1-position on the ring of menthol S instead of R
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6 views

How does double bond placement, in an alkene, affect the boiling point of the alkene?

Will having the double bond be closer to the middle of the molecule result in a higher or lower boiling point than an isotope with the double bond closer to one of the ends? Also, does the same ...
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1answer
21 views

why Tin/Zinc alloys can be used to solder aluminum and Tin alone does not "wet" the aluminum?

It is impossible to solder aluminum with only tin, tin does not "wet" aluminum surface because of the instantaneous reaction aluminum/oxygen on the surface of the base metal (aluminum). I ...
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0answers
12 views

Organic Chemistry II [closed]

Someone help 1) Place the reagents needed to perform the following above the arrow transformations, further classify the reaction as oxidation or reduction:
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0answers
15 views

M-bromoanisole preparation [closed]

I use nucleophilic substitution reaction in the preparation of m-bromoanisole from m-bromo nitrobenzene and potassium methoxide ( in presence of potassium hydroxide and 30 % tetrabutylammonium bromide)...
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0answers
5 views

Which from does casein take milk and after extraction?

In this video, NileRed said casein is exists in milk as a salt Calcium caseinate. And that structure of the salt is composed of ...
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0answers
16 views

How to learn the basics of Chemistry as early as possible because I didn't get them correctly in my earlier classes? [closed]

I am a student studying in class 8. I didn't get the basic things about chemistry in 6th and 7th grade as their was a pandemic and I didn't focus on studies much in those two years. Now I am facing a ...
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0answers
9 views

How to calculate molar mass and molecular formular of compounds [closed]

A 7.85g of compound with empirical formula C5H4 is dissolved in 301g of benzene. The freezing point of the solution is 1.05C beelow that of pure benzene . What are the molar mass and molecular ...
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1answer
37 views

Effect of amount of substance on equilibria

Considering the two equilibriums below, when the $[\ce{H+}]$ decreases, my book says that equilibrium \eqref{rxn:2} will shift to the left by a greater extent compared to equilibrium \eqref{rxn:1} ...
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0answers
16 views

Converse of ΔU = 0 for isothermal processes: is it true?

For an ideal gas undergoing an isothermal process $\Delta U = 0.$ But is the converse true? Let's say, $\Delta U$ for an ideal gas is zero. Is its temperature constant then? Can we say that it's ...
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1answer
26 views

Dilute a known volume and concentration acid with unknown volume water to obtain a specific pH

Dilute $\pu{10.0 mL}$ $\ce{HCl}$ $(\pu{12.0 M})$ to obtain a $\mathrm{pH}$ of $2.40$. How much water do you need to add? I can calculate the original $\mathrm{pH}$ from $c(\ce{HCl})$, hereafter $[\ce{...
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0answers
31 views

Why do the splitting pattern on my NMR differ from those stated in literature?

I attempt the synthesis of p-toluic acid using the Grignard reagent (prepared from 4-bromotoluene and Mg) and dry ice. The NMR of the raw product was recorded using $\ce{CDCl3}$ and a peak showing ...
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1answer
19 views

How to apply a certain voltage vs SHE

For one of my projects, I must apply a voltage at the electrodes of -1V and +2V vs SHE. But my device potentiostat picks a voltages of 3V. How am i certain that it doesn't apply the voltage between -...
-4
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1answer
34 views

Charge on O atom

Here it is seen that $\ce{O}$ donates one lone pair(2 electrons) to $\ce{B(OH)3}$,then how come only $+$ charge is formed on $\ce{O}$? Shouldn't $2+$ be formed since $2$ electrons have been donated? ...
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0answers
15 views

How to convert mg% to mg/mL? [closed]

In this paper radial immunodiffusion was used to determine immunoglobulin concentrations (in mg%, Table 3). How to convert mg% to mg/mL?
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0answers
7 views

carbonation test with phenolphthalein solution [closed]

I just buy a phenolphthalein solution and I want to use it for carbonation test but I'm confused if I can just use the phenolphthalein solution just like that or I must add ethanol in my ...
-4
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0answers
23 views

What results from the reduction of Hordenin? How is it possible that it has the same chemical formula as Ephedrine (C10H15NO)? [closed]

How is it possible that Hordenin Hydrochloride CAS 539-15-1 has the formula C10H15NO as well as Ephedrine Hydrochloride CAS 299-42-3 ?? So what happens by reducing Hordenin by a reduction reaction (...
-2
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0answers
10 views

Assessing concentration of a tincture [closed]

I am not a chemist. What equipment and process does one use to measure the concentration of a tincture (herbs soaking in 80 proof vodka over time)?
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0answers
18 views

How long do temporary dipoles last?

Theoretically, if you put 2 neutral atoms/compounds together in a controlled space with no external electrical fields, would a temporary dipole last forever, or would the jumping of electrons break ...
-1
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1answer
33 views

What volume does CO2 converted from O2 have?

Let's say a human inhales air that contains exactly 1 Liter of pure O2 (about 4.76L regular air) and no CO2. All at normal pressure. They manage to hold their breath until all the O2 has been ...
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0answers
24 views

What is the E-Z configuration of the following compound? [closed]

As per the CIP (cahn ingold prelog) rule what would be the E-Z configuration of the geometrical center to which the chlorine is attached?
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1answer
35 views

Is there any way to make ferrofluids float on water?

I am trying to do an oil spill clean up experiment, and I was thinking of using magnetism to clean up oil. I could make a ferrofluid/ferripaste using some type of oil, such as motor oil or mineral oil,...
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0answers
37 views

How to express concentration in terms of conversion of a component in parallel reactions?

Consider the following parallel reactions: $ \ce{2A <=> 3B} $ $ \ce{2B + A -> C} $ Where $\ce{A}$ is the limiting reactant, so chemical conversion can be rearranged to give the concentration ...
-4
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1answer
32 views

water to hydrogen to water

I'm trying to find out if there is any loss of water when converting water to hydrogen and then back into water and can't find an answer anywhere I've searched. I understand that the water produced is ...
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0answers
53 views

What's an example of something that is a strong base, and a strong oxidixing agent?

What so we have in chemistry for strong bases and strong oxidizers? And just watch how this will drift the thread away: I believe the answer is not column-1 oxides, or MnO2. Column-1 oxides are strong ...
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0answers
18 views

How much sildenafil citrate should I use if I want to infuse it with honey? Preferably 16 ounces of honey? [closed]

Honey vs sildenafil citrate I want to infuse them how much should I use?
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0answers
28 views

acetic acid 50% safety and storage

I need <5% acetic acid in some solutions (for microscopy) and if I am not wrong I need around 15-20% solution to be able to make these (other components like alcohols or glycerol I can find and use ...
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0answers
18 views

The reaction of magnesium malate with hydrochloric acid [closed]

I'd like to know the reaction of magnesium malate with hydrochloric acid. I couldn't find it on the internet and I'm worrying that ingesting mag. malate will neutralize my stomach acidity.
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0answers
17 views

Using a character table for H2O, NH3 and BF3 molecules please explain the following, [closed]

Using a character table for H2O, NH3 and BF3 molecules please explain the following, (1). Can there be triple degenerate orbital in the three molecules? (ii). What is the maximum degeneracies for the ...
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0answers
40 views

What is the correct expression for ionization constant of water?

I have seen two different formulas for ionization constant of water in two different books: $$ \begin{align} K_\mathrm{eq} &= \frac{a(\ce{H3O+})\cdot a(\ce{OH-})}{a(\ce{H2O})^2}\tag{1}\\ K_\mathrm{...
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1answer
27 views

How many characters does the SMILES notation uses?

I am not a chemist, in fact, I come from a computer science background, however, I am working on a project that involves using machine learning for SMILES generation. My question is, how many ...
-2
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0answers
12 views

Chemistry question about lipid absorption [closed]

Why triglycerols can't get absorbed directly into enterocytes? why do they have to be broken down then resynthesized?
-2
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1answer
40 views

Is each bag of plastic a polymer/macromolecule? If yes, why does it tear so easily? [duplicate]

For example, polyethene is a macromolecule. So each bag of polyethene should be one molecule. Doesn't tearing it therefore involve breaking strong covalent bonds? Shouldn't the energy needed to do ...
4
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0answers
62 views

Could a positron be made to stably orbit an atom?

Suppose you have a single atom of neon, argon or some other noble gas of your choice. While the entire atom is electrically neutral a nearby positron would probably be more strongly attracted to the ...
-3
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1answer
25 views

The meaning of USFDA (in cosmetics) [closed]

The full meaning of USFDA base on the definition of cosmetic meaning and production
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0answers
25 views

What's the absolute configuration of the 3' carbon on monophosphate adenosine? [closed]

Hi, I'm having difficulty finding the absolute configuration of the 3' carbon on this molecule.
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0answers
15 views

Self Limiting pH buffer for spas

is there a solid chemical that can be added to spas (hot tubs) that will act as a self limiting pH reducing buffer? I am thinking of how calcium carbonate can be used as a self limiting buffer to ...
-1
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0answers
28 views

Self-Charged Graphene Battery and Potential Chemical Reactions [closed]

Is it possible for a battery to be powered from ambient environment permanently, without violating any chemical/physical laws (under current technology)? I noticed a research paper which was done ...
0
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0answers
7 views

How to determine the chemical formula [closed]

I tried to explain these questions about stereochemistry, but there are still a lot of things I don’t understand. I don’t know why the answers to question (i) are AB and AB2, and how to explain other ...
-1
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0answers
21 views

Reversible Adiabatic Expansion

The initial pressure of an ideal I2gas is 5×104Pa. The corresponding volume is 3L. Thegas undergoes a reversible adiabatic expansion at room temperature to a volume of 5Lprocedures....
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0answers
21 views

Reactivity of potassium in water vs. in methanol [duplicate]

When potassium metal is added to water, it react violently, but when potassium react with methanol, it forms bubbles. Why is this happening? why is potassium more reactive in water than in methanol
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0answers
17 views

Work done when water expands [closed]

Liquid water one degree above the freezing point is put into a glass bottle, and a rubber stopperis put into the neck. The bottle is put into a freezer and after equilibrium is reached, ice has ...
-2
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0answers
20 views

Do I need to dilute HCl in a vitamin C titration with KIO3? [closed]

In a lab I'm looking at, in the instructions it says: "Dilute hydrochloric acid: (1 mol L−1)." I'm a bit confused how to do that.
-1
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1answer
39 views

How to separate manganese(IV) oxide and chromium(III) hydroxide?

I am trying to find a reagent that keeps either $\ce{MnO2}$ or $\ce{Cr(OH)3}$ solid and make other soluble so I can centrifuge or use filtration. I thought of $\ce{NaOH},$ but I could not find any ...
0
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1answer
36 views

Help determining Absorption Coefficient & Concentration from Uv-Vis reading

hope you're doing well. I'm having some trouble determining the absorption coefficient and concentration values of a protein from its UV absorption results. The experiment in question involves an ion ...
0
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0answers
26 views

How are these two enantiomers? [duplicate]

I was wondering how these two chair conformations are enantiomers, because they do not seem to be mirror images of each other. The molecule on the left undergoes a ring flip to achieve the ...
0
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1answer
39 views

What would the mechanism be for intermediate B to Supinidine, and what would by product C be?

I have managed to do the mechanism for the first step, but have no clue how 4 equivalents of MeLi are used for the second step of the reaction.

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