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3 views

Why does shampoo produce more foam than body soaps?

Soap and shampoo are both cleaning agents in our daily life. Why does shampoo produce more foam than body soaps?
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0answers
5 views

Limiting reactants and molar mass

So if in a balanced chemical equation, the mass of both reactants are equal then would there be a limiting reactant? Please help I am in need of help.
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0answers
4 views

Theory and formulation of gel aggregation?

I do experiment with a gellant that absorbs oil. When it has enough oil, it would create a big chunk (see #2); however, if it gets less amount of oil, it will make small spheres with a weaker adhesion ...
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1answer
10 views

Reaction between copper (II)chloride and aluminium foil

When I reacted copper chloride and aluminum foil instead of getting the brown color I got green color. Can anyone share their procedure where the experiment actually succeeded?
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0answers
15 views

Why does a strong base completely neutralize a weak acid?

For the longest time, weak acid-strong base titration curves completely baffled me. I understood that the equivalence point of a strong acid-strong base titration is reached when equal numbers of ...
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0answers
9 views

How do flame retardant vapors decrease over time?

I recently bought a new chair, and after unboxing and assembling it I noticed a very strong chemical smell. The chair cushions are made of foam and the upholstery is PU leather, so I'm assuming that ...
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0answers
14 views

Trimethylsilyl vs tert-butyl as activating substituent of benzene

Would trimethylsilane as a benzene substituent have an activating effect relative to tert-butyl for electrophilic substitution reactions?
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0answers
11 views

Why are these compounds classified as metamers?

Metamers are compounds having the same molecular formula but different number of carbon atoms, on either side of functional group. In the above compounds, the number of carbon atoms around the ester ...
1
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1answer
19 views

Calculating the solubility of cuprous iodide

I am clearly missing something obvious here. I get the $\mathrm{K_{sp}}$ from the CRC for $\ce{CuI}$ as $1\cdot10^{-12}$. So, $\ce{CuI-> Cu+ + I-}$ So the formula ought to be $$\mathrm{K_{sp}...
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0answers
19 views

Why is it experimentally difficult to accurately find the critical volume of a real gas?

I was reading up on the derivation of the values of various critical state functions( $\ce{Vc}$, $\ce{pc}$ and $\ce{Tc}$) from the Van der Waals equation (Physical Chemistry by G.W. Castellan). There, ...
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0answers
18 views

What is the formula for the rate of evaporation of methanol? [closed]

I want to increase the rate of evaporation of methanol by sucking off its vapour as it evaporates. Is it possible and can we mathematically show it? Also I want to produce a refrigeration effect so I ...
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0answers
12 views

What is pharmaceutical and chemical engineering [closed]

I want to know what is pharmaceutical and chemical engineering. What do they work. Is it good to study it.
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0answers
23 views

Why is H2Te the strongest acid among the following?

Among H2S, H2Se, H2Te the strongest acid is H2Te. The reason being that the bond strength in it the weakest so it dissociates easily. But my question is that why does it looses H+ in first place ...
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0answers
18 views

Morse interatomic potential

I am working with Morse interatomic potential, I searched through the Internet but I could not find any Morse parameters for Zirconium element. Is there any table, handbook or something like these ...
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0answers
11 views

What is a rotational-free signal transient?

I am unable to understand what is meant by this term, I encountered it on this paper. https://science.sciencemag.org/content/278/5338/658.full
2
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0answers
15 views

Curtin-Hammett principle to evaluate alkene insertion

Given an unsymmetrical alkene in a simple non-stereoselective catalytic hydrogenation reaction. If one would want to investigate the nuances in the catalytic cycle of a dihydride complex leading to ...
0
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1answer
16 views

What order would these compounds elute in a 3:1 hexanes:ethyl acetate TLC run?

I would figure the order would be (in order of smallest Rf to largest) W, Z, Y, X. Is the carboxylic acid more polar than the acetic anhydride?
3
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0answers
24 views

Discussion about Warren-Cowely Parameter

The Warren-Cowely Parameter (WCP) for short range solution order is defined as: $$\mathrm{WCP}_{ij} = 1 - \frac{Z_{ij}}{x_j \cdot Z_i}$$ where $Z_{ij}$ is the partial Coordination Number (CN) of ...
-1
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0answers
11 views

equilibrium reactions [closed]

How will the equilibrium of following reactions be affected 1) N2(g) + O2 (g) ⇄ 2NO(g); 2) 4HCl(g) + O2(g) ⇄ 2Cl2(g) + 2H2O(g) a) by rise of pressure; b) by decrease of oxygen concentration? Explain ...
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0answers
23 views

what makes a colloid particles lyophilic or lyophobic?

Why do some colloids don't precipitate(lyophilic) and some do(lyophobic)? Why is gold lyophobic, why does it need protective colloids also why does NaCl cause precipitation in gold sol?
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0answers
27 views

How many condensed tetracyclic aromatic hydrocarbons are there?

Recently I have been asked to sketch the chemical structures for every condensed tetracyclic aromatic hydrocarbon. I have managed to find 7 structures, but my chemistry teacher's solution was ...
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0answers
13 views

rate of SN2 reaction

In epoxidation of halohydrins when the carbons have more branchs (methyl) the rate of reaction will be incresed, than the halohydrin without methyl branchs? Whats the reason?
1
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1answer
15 views

Difference between “physical quantities” and “units”?

My textbook, Atkins' Physical Chemistry, 11th edition, by Atkins, de Paula, and Keeler, says the following: Although it is good practice to use only SI units, there will be occasions where accepted ...
-1
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1answer
35 views

Does vapour pressure affect evaporation and if so how can we use this to increase the rate of evaporation? [closed]

Could we reduce the vapour pressure by constantly sucking vapour from the liquid surface?
-5
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2answers
44 views

How can I add more electrons to copper? [closed]

In a galvanic cell, there are two reactions taking place. One is oxidation and other one is reduction. The reduction reaction is $\ce{Cu^2+ + 2 e- -> Cu}$. In this reaction, the copper 2+ ion ...
2
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0answers
31 views

Is strontium more metallic than sodium? If yes then why?

I got an MCQ in my examination, "Which one of the following is more metallic?" and the options were Sr, Na, Be or Aluminium. I know that sodium is more metallic than Be or Al but my mind stuck on ...
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0answers
10 views

How to calculate the amount of solid soda added to increase the pH of a solution [closed]

0.1 mole of HCN and 0.01 mole of AgI are in solution in 1 litre of water. We add solid soda to increase the pH of the solution. Ka(HCN/CN-)=10^-9.2 Ks(AgI)=10^-16 KD(Age(CN)^- 2)=10^-21 When the AgI ...
-1
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0answers
28 views

How is HCl relevant in the reaction of iodomethane and ammonia? [closed]

The following reaction is conducted using $\pu{1.8 g}$ of $\ce{CH3I}$ and $\pu{250 mL}$ of a $\pu{0.2 mol L-1}$ solution of aqueous $\ce{HCl}$. $$\ce{CH3I (l) + NH3 (aq) -> CH3NH2 (aq) + HI (aq)}$...
1
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1answer
21 views

How to determine the pH of citrate buffer system

I used this table (http://microscopy.berkeley.edu/Resources/instruction/buffers.html) to make a citrate buffer system. The Pka value is 6.4, and I multiplied the solution by ten to make a larger batch....
2
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1answer
29 views

Frequency region and “uncoupled oscillators” in vibrational spectroscopy

I am currently studying the textbook Infrared and Raman Spectroscopy by Larkin. In the first chapter of the textbook, the author presents the following table and accompanying explanation: The ...
1
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1answer
28 views

What is the relationship between concentration and voltage in a galvanic cell? How do you calculate the theoretical?

I am a year 12 Chemistry student and I was wondering if you could help me with some questions I have about a Galvanic cell experiment? I am doing an experimental report in Chemistry. The experiment I ...
4
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0answers
28 views

Enantiomers to diasteroisomers (rotational spectra)

Enantiomers have identical rotational spectrum because their mass distributions are identical. Recently a trick has been introduced in microwave spectroscopy in which a enatiomerically pure gas chiral ...
-1
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0answers
29 views

Basic Distillation Setup for home experimentation [closed]

If I am in the wrong section please let me know so I can repost/have it moved to the correct location. So I am currently trying to get into distillation, I have some potential uses for it in my line ...
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0answers
22 views

Could I polymerize or cross-link agar biopolymer to increase molecular weight?

I have synthesised a biomaterial using 12 grams agar powder, 18 grams glycerol and 400ml water. I have tried different formulas mainly being reducing the amount of glycerol and water but the physical ...
-1
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0answers
21 views

How are surgical masks manufactured? [closed]

After some research, I found the most common surgical masks are 3-ply type II. They have 3 layers of polypropylene, one is the filter and the other 2 are for protection. They filter between 98 and 99% ...
2
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2answers
41 views

Can you approximate the change in entropy of a reaction?

I found a problem in which I am given a hypothetical reaction in which from 2 liquids (reactants) I get 4 moles of gas and 1 mole of a solid substance (products): $$\ce{A (l) + B (l) -> 4C (g) + ...
-1
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1answer
32 views

How is silica gel made? [closed]

How is silica gel prepared from sand (after extracting it). How many ways can it be used? Is there a way to make it without an oven?
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0answers
27 views

Computing the work (thermodynamics) [closed]

first of all sorry for my bad english - it is not my native language. Let's say that there is a procces (1->2) where PxT= const. How can we calculate the work of this proccess? For instance, if the ...
4
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1answer
104 views

Hessian Matrix and Physical directions: Potential Energy Surface

How do the eigenvectors of the Hessian Matrix for potential energy surface correspond directly to the physical directions of translation, rotation and vibration? I see that they might correspond to ...
-1
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0answers
26 views

Effect of sugar in inhibiting oxidation rate of ascorbic acid in a closed system [closed]

I am a high school student working on a lab investigating the relationship between the concentration of sugar added to orange juice and vitamin c content (measured by DCPIP titration). I have read ...
-1
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0answers
17 views

Carbonylation of Ether [closed]

What is the reaction mechanism of the following reaction: $ ROR+CO $->$RCOOR $ I tried to search but couldn't find online.
-1
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2answers
54 views

Given that they contain an OH group, why do carboxylic acids not act as base? [closed]

As far I know carboxylic acids have a OH group but during dissociation only hydrogen gets separated. The CO moiety is polar, demonstrating that oxygen is much more electronegative than carbon. Why ...
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0answers
23 views

if we a have a molecule can we calculate its energy as a whole with it bonds electrons and protons and neutrons and to how match accuracy [closed]

sry i well explain better and simplify if we a have a molecule can we calculate its energy as a whole with it bonds electrons and protons and neutrons and to how match accuracy
-2
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0answers
26 views

Period of palladium [closed]

The configuration of palladium is 2,8,18,18. Then what is it doing in the 5th period? Is there an explanation without the concept of subshells?
3
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1answer
1k views

What does (sol) in a chemical equation mean?

I'm reading Shrivers Inorganic Chemistry book and some of the equations have a (sol) state on them. I'm sure the book has already defined this but I cannot find where. Examples: \begin{align} \ce{[...
1
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1answer
28 views

How can there be concentration and pressure terms simultaneously in the Nernst equation?

In the Nernst equation we are taught that the reaction quotient can have pressure terms and concentration terms simultaneously. According to my knowledge this does not happen anywhere else, so why can ...
-1
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0answers
18 views

Which one of these products is the most stable? [closed]

Which one of these products is the most stable, and why?
5
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1answer
37 views

Can density functional approximations including dispersion correction perform worse than without it?

I am trying correlate some experimental properties of a molecule to its calculated equilibrium geometry. To do so, I calculated the geometry and energy of some conformers. Now, I obtain mixed results ...
2
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1answer
39 views

Only valence shell electrons participate in bonding then how is Cr in H2CrO4 forming 6 covalent bonds although it has only 1 valence electron?

The structure of $\ce{H2CrO4}$ is as follows: Shell configuration of chromium is 2,8,13,1 i.e. it has only 1 valence electron and only valence electron participate in bonding but Chromium in the ...
1
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0answers
24 views

Understanding the gaff2.dat proper dihedral parameters

I have a project where I'm trying to program my own force field, and I decided to use the AMBER gaff2.dat force field parameters. However, I am really struggling parsing the gaff2.dat file when it ...

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