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2
votes
0answers
26 views

Increasing concentration of acetylcholine via SPE

I am trying to increase the final yield of acetylcholine (ACh) in my biofluid samples. I need to get the yield high enough for high confidence annotation of ACh (currently all I can really say is that ...
-3
votes
0answers
26 views

How can I make rose water with rose oil? [on hold]

I want to make rose water with natural Rose essential oil, please let me know how I can mix this oil with water to be homogeneous solution. The mix will be 1 oil to 1000 water. Thanks. Vahid
2
votes
1answer
20 views

What is the equation for solving the concentration of the unknown from a Single-point Standard Addition Calibration for Potentiometry?

I know how to use the standard addition equation for a single-point analysis from an equation I got from the Analytical Chemistry book "Quantitative Chemical Analysis" 9ed by D. Harris. However, ...
0
votes
1answer
65 views

How do I solve this problem on Mole balance?

Zinc oxide is reduced at a constant temperature in a closed reactor using ZnO(s) and C(s) as the only starting materials.The following reactions are assumed to be at thermodynamic equilibrium. $ZnO(s)+...
-1
votes
0answers
43 views

Correlation between dipole moment and stability

I have calculated optimized geometries and energies in water of two diastereomers of one compound. One turned out to be 1.9 kcal/mol more stable than the other (level of theory PBEo-G3bj/6-311g++(d,p)/...
-1
votes
0answers
22 views

Reaction between TiCl2 and Cl2 and 600 degrees C [closed]

Will TiCl2 (s) and Cl2 (g) react to form TiCl4 (g) at 600 degrees C?
2
votes
0answers
68 views

What produces this NMR spectrum? [on hold]

I'm having difficulty deciphering this 13C and 1H-NMR spectra. I've tried figuring it out, and have gotten close and am pretty sure it contains a methoxy group attached to a benzyl group, but hit a ...
-4
votes
0answers
29 views

How to water with high oxidation reduction potential? [on hold]

I'm looking for a process to maximize ORP (negative milivolts) with do-it-yourself methods. One way would be to use a reductor (electron donor) and simply dissolve it, other would be to use ...
0
votes
1answer
43 views

Preserved flowers in epoxy resin [on hold]

I want to cast flowers in resin. The problem is that everyone is casting dried flowers in order to prevent the moisture from fresh flowers evaporating while the resin is curing and I need to cast ...
7
votes
2answers
630 views

Why is tert-butoxide often used in elimination reactions when it is not necessary?

I understand that tert-butoxide is used to favor the Hofmann product in elimination reactions due to its steric bulk (and thus inability to abstract a proton in a more substituted position); however, ...
0
votes
0answers
50 views

Preparation of 3-ethylpentan-3-ol

Is it possible to use CI3TMS (a carbon with three iodo groups and a trimethylsilyl protecting group) and three equivalents of an ethyl grignard reagent to prepare 3-ethylpentan-3-ol? By deprotecting ...
-3
votes
0answers
18 views

What does electropositive element do? Does it attract electrons? [closed]

Does electro positivity has an effect on electrons?
0
votes
0answers
29 views

What is the logic behind a 28% ammonia solution being labeled as 56.6% in ammonium hydroxide? [on hold]

I assume it's just that the molecular mass is twice as large than ammonia's. Also, are we assuming 100% conversion in the reaction or not, given that's a weak base at 25C? This whole thing is kind of ...
0
votes
0answers
43 views

Purifying Potassium-40

What method is commonly used for separating out potassium-40 from natural potassium with a purity grade around 95% or more? How much would one kilogram of potassium-40 cost if this method is used?
1
vote
0answers
42 views

Calculating ionic strength and pH of a buffer solution [on hold]

Im trying to calculate ion strength and pH of solution. Components of the solution: 47 ul of 1000 pmol DNA in Elution Buffer (10 mM Tris-HCl pH 8.5) was bound to 3 ul of 10 µM YoYo1 (flourescent dye) ...
-3
votes
0answers
16 views

Chemical bonding back bonding [closed]

Which has strongest bf bond Bf3 BFHCl Bf2h Bf4-
-3
votes
0answers
16 views

Foaming agent and ssoap [closed]

What is the formula for just the foam in shaving cream or hair mousse and what is the formula for a soap that could be added to it?
-3
votes
1answer
35 views

How to avoid cannizaro reaction during aldol reaction? [on hold]

I am doing some Aldol reaction in lab,problem is **basically one of my Aldehyde is converting largely in cannizzaro products.**Please suggest me which base I can use so that I will not get cannizzaro ...
-1
votes
1answer
18 views

Comparison of boiling points via hydrogen Bonding [on hold]

1)Boiling point of ethanol is more than that of ethanamine but boiling point of ethanoic acid is less than that of ethanamide...why is this so? I understand that the approach would be to check the ...
-1
votes
1answer
26 views

How should I interpret and present my total protein amount? [on hold]

I have a problem. I have purified a protein with method A and then B. After method A I have a protein concentration of 20 mg/ml and after method B a concentration of 18 mg/ml. Method B is dialysis and ...
-1
votes
0answers
27 views

Two methods for calculating ΔH yield different results [on hold]

A problem in my book says: $\pu{140 g}$ of $\ce{N2}$ (perfect gas) changes from $\pu{200 K}$ to $\pu{400 K}$ at constant volume. Calculate the change in internal energy $\Delta E$ and the change in ...
0
votes
0answers
5 views

What causes a binder (like silicone resins) to inhibit the proper evaporation of water from curing grout? [on hold]

While investigating various tile grouts, I read, "What is a polymer in grout?These grouts are water-based and use polyurethane, acrylic polymer, and/or silicone resin for the binder, in place of ...
-1
votes
0answers
22 views

Which law governs the effect of temperature on the solubility of a gas in a liquid? [on hold]

Which law governs the effect of temperature on the solubility of a gas in a liquid? Boyle's law Charles law Henry's law Avogadro's law This was a multiple choice question in our ...
6
votes
2answers
278 views

Why is the Lucas test not recommended to differentiate higher alcohols?

I read about the Lucas test for alcohols in which a cloudy precipitate is produced with a tertiary or secondary alcohol. However, on a side note it was mentioned that this test is useful only for ...
0
votes
1answer
27 views

Doubts Regarding Ceric Ammonium Nitrate Test for Alcohols

I read about Ceric Ammonium Nitrate Test for Alcohols and a red colour is produced if the solution has an alcohol functional group however as a side note it was mentioned that this test is only useful ...
4
votes
1answer
44 views

Searching for a solvent with a low carbon dioxide solubility

I would like to use a liquid solvent for some experimentation with a carbon dioxide solubility as low as possible under usual pressure and temperature conditions (say, $\pu{1 atm}$ and $\pu{293 K}$). ...
-1
votes
0answers
9 views

Uncertainty calculation help! Eyring Plot [closed]

If I am looking at the Eyring equation, lnk/T = −ΔH†/RT + lnkB/h + ΔS‡/R, how can i proceed with my uncertainty calculations?
3
votes
0answers
15 views

Doubts Regarding Compounds Which Can Give Aniline Dye Test

I read that to test for the presence of Phenol Groups in an Organic Compound Aniline Dye Test can be performed. If the solution has phenol present it gives a red or orange precipitate to confirm the ...
1
vote
1answer
20 views

CO-vibration in metal carbonyl

I'm struggling to understand the trend of $\ce{CO}$-vibration in isoelectronic metal carbonyls. $$ \begin{array}{lr|lr} \hline \text{Compound} & ν/\pu{cm-1} & \text{Compound} & ν/\pu{cm-1}...
-2
votes
0answers
29 views

Calculate pH of final solution using volume and pH of initial solutions [closed]

I have an 800mL solution of TBS (pKa=8.06), HCl, and water at a pH of 7.61 to which I add 200mL of pure 7.0 pH water. What is my final pH? Please show me the calculation too.
1
vote
0answers
22 views

What is total enthalpy?

I've seen that it's defined as $h_0 = h + \frac{v^2}{2}$, where $h_0$ is the total enthalpy per unit mass. I can see that the $\frac{v^2}{2}$ term probably has something to do with kinetic energy, but ...
5
votes
0answers
53 views

Why does ethene not disintegrate upon excitation?

The average c=c double bond has somewhere around 614 kJ/mol of energy, if we convert it to eV, then the bond strength is roughly 6.4 eV. Additionally, Ethene absorbs light at 171 nm. However, if we ...
2
votes
0answers
20 views

How to remove the foggy discoloration in polycarbonate tubes caused by acetone?

Unknowing that the tubes used in the centrifuge are made of polycarbonate, I cleaned them with acetone. Following, a white smoky discolouration appeared and the tubes turned opaque. Is there any way ...
1
vote
0answers
8 views

Lattice Energy of MX2 type

While finding the solution to the question that which among BaO and BaCl2 has hi that is energy I found that it was BaO whose lattice energy is high and there were explaining it just with charges. So ...
1
vote
0answers
15 views

Question in stereoisomerism

Question: For the following compound, find Total number of stereoisomers Number of optically active stereoisomers Total number of fractions on fractional distillation of all ...
2
votes
0answers
17 views

Chirality in carbocations

The following compound is a carbocation. Clearly, the given compound does not have any element of symmetry. The compound is non planar due to the presence of ethyl group. Thus it must be chiral. But ...
0
votes
0answers
22 views

Lewis dot structures of carbonate, nitrate and phosphate anions

According to the Lewis dot structure, which of the following anions has more than 4 bond pairs around the central atom? 1) carbonate anion 2) nitrate anion 3) phosphate anion 4) none of ...
1
vote
1answer
44 views

Do external electronic shells influence internal ones?

There is a well-known electron shielding effect: negatively-charged internal electronic shell screens external shells from positive nuclei, thus increasing their radii. Thus, 2S orbital radius of Li ...
0
votes
1answer
53 views

Which compound has resonance structures? [on hold]

Which compound has resonance structures? A. $\ce{C6H12}$ B. $\ce{CH3CHO}$ C. $\ce{NaBr}$ D. $\ce{Na2CO3}$ The answer key says D is correct, but I do not understand why $\ce{Na2CO3},$ which ...
-2
votes
1answer
16 views

what is the major source of D&L aldoses and ketoses [on hold]

as i understand to this subject, if the OH is on the left then it is L, and if on the right then it is D, but what is the major source, and function of it?
-1
votes
1answer
29 views

How to estimate the maximum chlorine hazard from 1 g of Palladium(II) chloride? [on hold]

I plan to work with an electrolyte that contains 1 g of Palladium(II) chloride. I am trying to estimate how much of a hazard this system could possibly pose (and provide ventilation, chlorine ...
-3
votes
0answers
34 views

Wrong naming of orbitals [closed]

Well I was wondering since the 1s orbital in hydrogen has higher energy than the 1s orbital in lithium should we change the naming of it ? We can call it 1s-H orbital..and 1s-Li orbital.
-1
votes
0answers
12 views

Empirical and Molecular Formulas of a Compound from Masses after Combustion [closed]

In my Chemistry Homework, there is a problem which asks this: A compound contains only hydrogen, carbon, and oxygen. Combustion of 10.68 mg of the compound yields $\pu{16.01 mg} \space \ce{CO2}$ ...
2
votes
0answers
29 views

Are there any forbidden collisional electronic transitions?

There are spectroscopy selection rules marking some radiative electronic transitions as forbidden. For example, it is stated that single electron of H atom can not move from S2 to S1, or from P2 to S2 ...
-1
votes
0answers
35 views

How to separate tin from unknown elements? [closed]

Usually in electronic soldering, something like the following photo will be happened. at this time, is there any way to separate tin from unknown elements?
-1
votes
0answers
17 views

More shells as principal quantum number increases [closed]

Why do more shells open up as n increases? As in why does n = 1 only have 1s but n=3 have 3s, 3p, 3d? Does it have something to do with the magnetic quantum number?
0
votes
0answers
36 views

Reacting ZnSO4 with KCl

I'm considering the following reaction: $\ce{ZnSO4} + 2 \ce{KCl} \ce{->} \ce{ZnCl2} + \ce{K2SO4}$ The high solubility of $\ce{ZnCl2}$ would favour the $\ce{ZnSO4}$ & $\ce{KCl}$ direction of ...
4
votes
1answer
65 views

Finding mathematically the ground state density in DFT

To find the ground state density in DFT, you set the following Lagrangian: $$L = E[\rho(\vec r)] - \mu\left(\int \rho(\vec r) \mathrm{d}\vec r - N\right)$$ While minimising with respect to the ...
-3
votes
0answers
25 views

Reaction of carbonyls with alcohol

Why dont ketones react with mono alcohols to give acetals unlike aldehyde? They are very similar and almost share all general reactions. However, there was no reaction of ketones with mono alcohol but ...
-1
votes
0answers
16 views

Absorption of salts, like calcium carbonate, in the intestine [on hold]

After absorption, does calcium carbonate from antacids appear in the blood as calcium carbonate or as calcium + carbonate? Is there any general rule about this for inorganic salts, like iron sulfate? ...

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