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3 views

For sequential extraction is the reagent pH adjusted or is it the sample with the reagent that's pH adjusted?

I'll be doing sequential extraction on ash samples, and I'm not sure whether the procedure indicates to adjust the pH of the reagent or the pH of the mixture (reagent with sample)? I copied and pasted ...
1
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0answers
6 views

Friedel-Crafts acylation with withdrawing group?

Will a Friedel- Crafts acylation take place on ortho-bromotoluene? I do understand that Friedel Crafts reaction does not occur when there is an electron withdrawing group on the ring but is there any ...
1
vote
0answers
10 views

Acid catalyzed bromine substitution in an alcoholic ester. What is the major product and why?

This was in a paper I gave. I want to know the mechanism by which both of these products will be formed and why is the 1st one the major product. My thinking is that the -OH group will be converted ...
0
votes
0answers
11 views

Why does pure alpha glucose powder clump when attempting to dissolve in water and become very hard?

I noticed that when I attempted to dissolve some pure alpha glucose powder in water, it would become hard and clump at the bottom of the beaker if I dumped it into the beaker all at once. It was ...
0
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0answers
12 views

Krazy glue (cyanoacrylate) and methyl acetate, gas produced?

I added a nail polish remover substitute (main ingredients: methyl acetate, isopropyl myristate) to krazy glue (cyanoacrylate) that was stuck on a surface of painted metal (and some plastic parts). It ...
0
votes
1answer
22 views

Energy required to break apart water molecules in dissociation?

I'm learning about the process of dissociation. I'm aware in dissolution that essentially three processes occur (I know I may be simplifying it, but I am in Year 11): Solute particles break apart (...
-5
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0answers
30 views

Does Phenol + FeBr3 +Br2 forms para bromo phenol or not Please Help as it's gonna decide my future [closed]

According To me it wouldn't form para bromo benzene as FeBr3 is a lewis acid and form dative bond with oxygen atom and it will form -HO-Fe(Br)3+ and its meta director as well as deactivating group so ...
-2
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0answers
14 views

How easily can bisphenol A used in polycarbonate plastic containers “leak” into the water that they hold? [closed]

Considering circumstances where the water bottle is indoors at room temperature and not exposed to any extreme heat or forms of impact. How would the BPA separate from the plastic into the water?
-2
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0answers
15 views

Internal Energy of a System [closed]

Can the Internal Energy of a system change without changing it's temperature? And why in isothermal expansion of a gas the change in internal energy is zero?
-1
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0answers
19 views

Does anyone know how to precipitate silver from Silver sulfadiazine? [closed]

I have a quantity of Silvadene or Silver sulfadiazine. I’m wondering if anyone knows how to extract pure silver from it. Thanks in advance.
0
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0answers
20 views

Does pairing of electrons release or consume energy?

While studying Crystal Field Theory, it was said that low-spin complexes only form when the Crystal Field Splitting energy exceeds the pairing energy of electrons. What I infer from this is that it ...
-1
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1answer
35 views

Questions about molar ratio

I am new to chemistry so this might be about a very easy concept that I might be misunderstanding but I would appreciate your help! I watched a video of combining hydrogen and oxygen and forming water....
1
vote
0answers
47 views

How do I get calcium citrate to precipitate in experiment on extraction of citric acid from juice?

I was planning to extract citric acid from mango juice by first using Aspergillus niger fungus by fermentation to convert the mango juice to citric acid, then extracting by first adding sodium ...
-2
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0answers
20 views

Is Long Term Preservation of Acrylic Possible? [closed]

Is there anything that could be done to preserve/stabilize acrylic objects on long-term timescales or is decomposition inevitable?
-1
votes
1answer
35 views

Comparing strength of Sigma bond strength formed by orbitals

According to my professor $d_{z^2}-d_{z^2}$ sigma bond is stronger than $p_z-p_z$ sigma bond as the extent of overlapping is more in $d_{z^2}-d_{z^2}$ overlap, because of directional nature and of $...
-4
votes
1answer
39 views

How Bread is made with yeast, sugar and luke warm milk? [closed]

Materials and Apparatus: wheat flour sugar dry yeast glass bowl covering plate milk Procedure: Lukewarm milk is taken in the glass bowl and sugar is added to it. Then, yeast is added to the same. ...
3
votes
0answers
31 views

Rotating orbitals and parameters for a many-body calculation

I am confused with some results I am getting. Given a molecule (In particular, I was toying with triangulenes, some benzenoids and things like that, but this is not very important), I perform first a ...
-1
votes
0answers
22 views

How exactly does fractional distillation work? [closed]

Fractional distillation has an ability to separate substance with less than 25 Kelvin difference in their boiling points. But how? There’s a fractionating column with glass beads. But I can’t ...
1
vote
0answers
52 views

Why does tennessine have a larger (predicted) electron affinity than nihonium?

According to Wikipedia, tennessine has an electron affinity (EA) of $\pu{+166 kJ mol-1}$ and nihonium $\pu{+67 kJ mol-1}$. Normally this would make sense since tennessine is in group 17 and nihonium ...
2
votes
0answers
44 views

Etard's reaction

My textbook says the following on Etard's reaction: Now, if the alkyl group attached to benzene is an unsymmetrical or branched alkyl group, such as this: What will be the reaction product(s)? Which ...
0
votes
1answer
36 views

Setting up reactor in inert atmosphere

I am searching for reactor set-up that can maintain inert atmosphere, and found that many organic synthesis labs use Schlenk line. But organic synthesis is not main thing of my lab, so there is some ...
-3
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0answers
21 views

Amount of Oxygen needed underwater at approx 1atm pressure [closed]

Scuba diving means diving underwater with the help of diving equipments. Scuba divers can dive upto 65-90ft underwater. The pressure of seawater at a depth of 33m below sea level is equal to 1atm. The ...
5
votes
1answer
264 views

Reaction of phenol with phosphorus tribromide

I know that aliphatic alcohols react with reagents like $\ce{PBr3},$ $\ce{PBr5},$ $\ce{SOCl2}$ etc. to give alkyl halides as a product. But what will happen if we put aromatic alcohols like phenols ...
-1
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0answers
42 views

Are butane, hexane, octane, and the remaining “even” alkanes considered polyethylene? [duplicate]

If a polyethylene chain contains hydrogen at its ends, isn't it just an alkane with an even number of carbons? Is there any distinction between polyethylene and even alkanes that I'm missing?
-1
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0answers
36 views

What is N2O4 used for in organic synthesis? [closed]

Hi I came across N2O4 in my organic chemistry class and before I could ask, my teacher went ahead, so can someone please help me out and tell me what N2O4 is used for?
-1
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0answers
23 views

Irregular trend in the first ionisation enthalpy of 3d elements

I was studying my textbook and I stumbled upon this part. The irregular trend in the first lonisation enthalpy of the 3d metals, though of little chemical significance, can be accounted for by ...
0
votes
0answers
18 views

Does increasing size of an alkyl group attached to the central carbon atom have an effect on the H - C - alkyl group bond angle?

Does increasing the length of the alkyl group attached to a central carbon have an impact on the bond angles of the tetrahedral structure of the central carbon (the alkyl groups being methyl, ethyl, ...
0
votes
1answer
40 views

Removing alkaline stain with acid

Professor Robert Winston once removed a blue alkaline stain using carbon dioxide from a fire extinguisher on James Corden's show. Here's the link for the episode I would like to know if there is a way ...
-1
votes
0answers
36 views

Predicting possibility of oxidation by observing Standard oxidation potential

How can we judge possibility of oxidation by seeing the oxidation potential? OR What is the relation between Standard oxidation potential (S.O.P.) and quality of oxidation ? By quality I mean the ...
6
votes
1answer
90 views

Why do purple Pedialyte freezer pops turn green when frozen?

I bought some Pedialyte freezer pops for my kids: And I've noticed that after spending a long enough time in the freezer, the purple "grape" pops change color from purple to green: After ...
-2
votes
0answers
20 views

Unstable liquid ethanol based hand sanitizer pH and color [closed]

I have a question. We are producing 71% denatured ethanol (denaturants - less than 1%: MEK, denatonium benzoat and IPA). We add glycerine as a hand moisturizer inside and pH is stabilized with citric ...
4
votes
0answers
39 views

Tautomerism between cyclohex-2-en-1-one and cyclohex-3-en-1-one

I think cyclohex-2-en-1-one and cyclohex-3-en-1-one should undergo tautomerism as shown below: I'm calling it tautomerism because of it's similarity with the tautomerism mechanism in basic medium. I ...
-1
votes
1answer
13 views

Calculating Heat of Solution of a Compound comparing to other compound data

For example if I have a table with these data How can those data be compared with each other to find heat of solution of $\ce{KI}$?
5
votes
0answers
72 views

Mechanism of reaction of ketones with isoalkanes under conc. sulfuric acid and heat

Taken from the book of GOC by Dr. O.P Tandon, Himanshu Pandey, Dr. A.K. Virmani, Can anyone elaborate on the mechanism?
-1
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0answers
13 views

Calculating the concentration of ammonia solution [closed]

If 20gm of ammonia gas is dissolved in 1 liter water, then what will be the concentration of the solution?
0
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0answers
53 views

Is Copernicium a transition metal?

Zinc, cadmium, mercury and copernicium belong to the group 12 of the periodic table. In my textbook , it is mentioned that zinc, cadmium and mercury are d-block elements, but not transition metals. ...
-2
votes
0answers
40 views

Is there a difference in energy between spin up and spin down electron? [duplicate]

Usually when we write the orbital diagram of elements, we fill the empty orbitals with up-spins and then after all the slots for a particular $l$ is filled, we pair the down spins as well. But, could ...
-1
votes
0answers
14 views

What is the physical basis of the reversal of the order of filling due to s-p mixing? [closed]

what exact changes does sp mixing bring about to molecular structures which leads to the 𝝅2px=𝝅2py orbital being filled before the σ2pz orbital?
1
vote
1answer
75 views

Find the ion with mass number 37 if the ion contains 11.1% more neutrons than the electrons

An ion with mass number 37 possesses one unit of negative charge. The ion contains 11.1% more neutrons than the electrons in its nucleus. An ion with a mass of 37 has % negative charge compared to % ...
-2
votes
0answers
11 views

Distortion of electron cloud of anion when going down Group 2. (Thermal stability) [closed]

My teacher said that the if more heat is given, it is easier to distort the electron cloud of anion. Is this correct?
-1
votes
2answers
47 views

what happens if iron clamp is attached to a copper pipe to a wall?

I'm guessing its not a good idea, since iron will then corrode easily (also depending on the location and environment), Although copper do not rust it will increase the rate of it from oxidizing. plus ...
2
votes
1answer
68 views

Confusion in R/S Nomenclature and Chirality

I have many confusions regarding optical isomerism: What is the use of the R/S nomenclature? I understand that it is used to distinguish between the different spacial arrangements that are possible ...
8
votes
1answer
81 views

Why does LiAlH4 reduce the double bond of cinnamaldehyde, whereas it does not reduce the double bond in crotonaldehyde?

$\ce{LiAlH4}$ is a strong reducing agent capable of breaking the double bonds. It does break the double bonds in cinnamaldehyde. Shouldn't $\ce{LiAlH4}$ be able to break the double bond in ...
-4
votes
0answers
15 views

What is the suitable amount of in the given reaction EDC [closed]

chitosan (200 mg) was dissolved in 20 mL of 1.25% acetic acid solution, and VES (600 mg) was dissolved in 25 mL absolute ethyl alcohol followed by the addition of a suitable amount of EDC, what is the ...
1
vote
0answers
49 views

A liquid which climbs out of its pot [closed]

My Russian born wife recently asked me to buy her a skin remedy widely used in Russia. In English this is the oil of a plant called Sea Buckthorn. It is a thin yellow liquid. My wife put some of this ...
2
votes
1answer
80 views

Why is hydrogen peroxide acidic in aqueous solution?

This seemed like a trivial question to me... until I began to think about it. The "usual" criteria for greater acidity are larger sizes of the atom attached to the acidic proton within the ...
-2
votes
0answers
13 views

Specific heat capacity of alcohol [closed]

A piece of iron of mass 0.27kg is immersed in a boiling water and and dropped into 0.10kg alcohol at 27°C. If the final mixture is 50°C, what is the specific heat capacity of the alcohol? (Specific ...
-1
votes
0answers
23 views

uv-vis same spectra [closed]

Hi there I am doing an experiment of uv assay of Dextromethorphan hydrobromide where its run under uv in two solutions an acitic acid and sodium hydroxide the uv results showed that both solutions had ...
3
votes
1answer
174 views

Reaction of naphthalene with sodium dichromate/sulfuric acid

I recently came across a question where naphthalene undergoes oxidation with sodium dichromate in presence of sulfuric acid. The given options were benzoic acid, phthalic acid, decalin, and tetralin. ...
2
votes
0answers
38 views

Exact nature of HOMO of square planar isomer of tetraamminemagnesium(0)

I need to calculate information about the (hypothetical) square-planar form of the tetraamminemagnesium(0) molecule as a reference to my personal QC research project; everything goes fine until we go ...

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