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52 views

Density g/cm3 of bleached viscose

I can find in literature what the density is for untreated viscose, but not for viscose that is bleached. Does this change the density? And what is the density for bleached viscose?
5
votes
1answer
20k views

Activation energy and temperature [duplicate]

It is said that activation energy does not change with temperature. But I am unable to figure out why. If we increase the temperature, the kinetic energy of the molecules will increase and they will ...
4
votes
2answers
147 views

How to identify an emerald green solution with possibly two anions?

The solution is emerald green in colour. When added with water, it gives a pale blue solution. When reacted with $\ce{BaCl2}$, it gives a sky blue solution and a white precipitate. When reacted ...
20
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1answer
3k views

Do only outer electron shells take part in forming chemical bonds?

Do only outer electron shells take part in forming chemical bonds? Or could an inner shell create a bond under some conditions?
6
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1answer
4k views

Periodic cleavage of carbohydrates

Carbohydrate like glucose undergoes periodic cleavage by $\ce{HIO4}$ and forms respective products are five moles of formic acid and one mole of formaldehyde. Here is my question , what is mechanism ...
3
votes
1answer
255 views

How does an electrolyte react to voltages below its electrolysis potential?

An electrolyte can be electrolysed by a voltage higher than the reverse reaction’s cell potential, while conducting a current in the process. But what happens at the electrodes when the applied ...
1
vote
1answer
134 views

How to figure out which two solutions will emit largest heat when they are mixed in same volumes?

How can I figure out which two solutions will emit the largest heat, when they are mixed in same volumes? Then let's assume that there are five pairs of solutions given: \begin{align} \ce{2NaOH +...
14
votes
1answer
431 views

Does the Battery Bounce Test actually work?

I heard that a good way to test if a battery is dead or alive is to see if it bounces. Supposedly, dead batteries bounce higher than living ones. Can someone tell me if this is a legitimate claim, and ...
12
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4answers
717 views

Quantum mechanical explanation for Le Chatelier's principle?

We know from basic chemistry that a reaction reaches equilibrium as described by Le Châtelier's principle. What's the quantum mechanical explanation to this principle? How a change in temperature/...
3
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0answers
64 views

Can one dichlorotriazine molecule form two bonds with cellulose?

In all the reactions I saw online, dichlorotriazine is shown to form only one bond with cellulose (example 1, example 2; paper). But cellulose has many potential sites for bonding. Can ...
9
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1answer
17k views

Why is a ketone not capable of hydrogen bonding among themselves?

The ketone has one oxygen atom in it and there are two lone pairs hanging out, both of which make it seemingly capable of hydrogen bonding. But in reality it is not. Did some research and found this ...
5
votes
2answers
5k views

Equilibrium constant when adding more of a reactant

Suppose I have the reversible reaction: $$\ce{A +B⇌ C} $$ The reaction is at equilibrium with equilibrium constant $K$ I am told that if I increase the concentration of $\ce{B}$, the rate for the ...
2
votes
1answer
287 views

How do I write many cyclic voltammetry curves in Nova?

We are making an electrochemical research on supercapacitors that involves checking stability of our material. That requires repeated writing of cyclic voltammetry curves. Our goal is to write at ...
7
votes
1answer
2k views

How to make lead nitrate from pure lead

Is it possible to add copper nitrate solution and lead so that a single displacement reaction occurs to yield lead nitrate. I recently melted lead and added cooper nitrate to the molten lead. I then ...
4
votes
1answer
137 views

Software for technical calculation of chemical reactors

I'm not a chemical engineer and don't have good background in it. Just my father asked me to do something for him, as I'm a computer engineering graduate. This is a software for calculation of ...
6
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0answers
122 views

Interstitial sites: edge and face sharing?

In close packed structures there is one octahedral hole per close packed atom. In a HCP unit cell these octahedra form a chain of face sharing polyhedra. Is this this universal in close packing or ...
15
votes
3answers
6k views

How does chromium help stainless steel prevent rusting?

Various sources (such as this one) say that stainless steel is stainless because a passivation layer of an oxide is formed, but I haven't found details on why chromium helps create this passivation ...
3
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1answer
368 views

OD660 readings of yeast

I am working on a yeast fermentation project, and I am getting final OD660 reading of 1.85 for different media: yeast extracts+cane molasses, nitrogen source+cane molasses, and glucose+cane molasses ...
4
votes
1answer
6k views

Do all double displacement reactions lead to precipitates?

I know that most of the double displacement reactions form some kind of precipitates as their products. But do all of the double displacement reactions form precipitates? I have searched on this site ...
10
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2answers
2k views

Ring expansion from a given cyclic carbocation

How will the cyclobutane ring behave in the case of cyclobutylmethylium (cyclobutylmethyl cation)? I initially thought there would be ring expansion to a five membered ring so that there may be less ...
2
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2answers
892 views

Calculating pH of an unknown base, and the pKb

The percent dissociation of a base $\ce{X}$ in a $0.002\ \mathrm{M}$ solution is $4.7 \cdot 10^{-3}\ \%$. What is the pH of the solution and what is the $\mathrm{p}K_\text{b}$ of base $\ce{X}$? The ...
2
votes
1answer
620 views

If for a chemical reaction the standard gibbs free energy is negative then :

If the standard gibbs free energy for a reaction is negative then the forward reaction will take place and the reaction will not be reversible. Is it true ? I have a problem understanding what is ...
12
votes
1answer
3k views

Why carbon nanotubes can act as a good electrical conductor?

Bulk carbon is an insulator, but at nanoscale (e.g. carbon nanotubes) carbon may become a good electrical conductor. If I am correct this means carbon nanotube band structure is metal-like. E.g. it ...
5
votes
1answer
72 views

Dissolving to Create a Solution with Ethanol

If at 95% Ethanol can dissolve chemical X at 1mg/1mL then theoretically if you have 500mg of chemical X you can dissolve it in 500mL of $\ce{EtOH}$ to get 1mg/mL correct? My question is, if you have ...
4
votes
1answer
207 views

Determining spin of metal complex

Is there any way to determine the spin of $\ce{[Fe(OH)6]^{4-}}$ without looking at the spectrochemical series?
5
votes
1answer
3k views

When is phosphorus a polyatomic molecule?

Phosphorus is listed as a single element in the periodic table; however, I see that it is also a polyatomic molecule as $\ce{P4}$. I am trying to determine the number of atoms of phosphorus in an ...
8
votes
1answer
184 views

Wavelength extention in AAS

Theoreticly, the width of the spectral line in AAS (atomic absorbtion spectroscopy) is 10^-5, but in fact there happens an extention of it and it becomes 0.002-0.005. There are some factors which ...
11
votes
1answer
2k views

Purpose of ammine in Tollens' reagent

In this previous question the mechanism for the reaction of Tollens' reagent was outlined. As I understand it the oxidising agent in Tollens' is the diamminesilver(I) complex $\ce{[Ag(NH3)2]+}$ but ...
5
votes
2answers
626 views

Bromine with 10 electrons

On a test question, my organic chemistry professor gave us a really big molecule and told us to give list the formal charges on each atom. There was a $\ce{Br}$ with 3 lone pairs and a double bond to ...
6
votes
1answer
280 views

Dissolving Aspartic acid in vinegar?

I am trying to dissolve aspartic acid into vinegar as use as a carbon source in saltwater aquariums. It does not dissolve. I was told to increase the pH and it will work? What is the best way to ...
5
votes
2answers
3k views

Carbon with two double bonds and oxygen name

I have a compound like this: $$\ce{CH2=C=O}$$ I wonder if it is a functional group or a normal group. As a functional group I couldn't find out. Is it a normal compound or a functional group and ...
3
votes
1answer
7k views

Benzylic and allylic carbocation stability order [closed]

Most books I have read stop at this order : Benzylic > Allylic > Tertiary > secondary > primary However If I want to compare tertiary, secondary and primary benzylic and Allylic carbocations what ...
6
votes
1answer
5k views

Burning a diamond produces how much energy?

How much energy is produced by burning a 1 ct. diamond? I'm trying to figure out how much energy to build the diamonds in a biological process. See here: https://worldbuilding.stackexchange.com/...
2
votes
2answers
155 views

Are the following expressions for base dissociation constant equivalent?

Given a weak base such as $\ce{C2H5NH2}$, I usually see the expression for $K_\text{b}$ as $K_\text{b} = \frac{[\ce{C2H5NH3+}][\ce{OH-}]}{[\ce{C2H5NH2}]}$. Are the expressions $K_\text{b} = \frac{...
3
votes
1answer
621 views

50-90'C color changing chemical to use as warning marker for hot electronics?

I am testing electronics with many potentially unstable contacts, and I wish to monitor if they rise above 50 to 90 degrees Celsius, i.e. using carbon paper that would darken progressively from 50 to ...
3
votes
0answers
95 views

Catering grade electrolysis of alcohol

Would the electrolysis of alcohol, specifically spirits, result in a potable end product? I'm looking for some novel cocktail ingredients.
4
votes
0answers
214 views

How do popular reducing agents react on compounds that have ester, carbonyl, and unsaturated functionalities?

Suppose we have a chemical compound like ethyl 4-oxo-2-cyclopentene-1-carboxylate It is $\ce{-COOC2H5}$ bonded to a five-membered carbon ring with one double bond and the ring has another carbonyl ...
12
votes
1answer
476 views

19F NMR of hexafluorobromine(VII) cation

$\ce{[BrF6]+}$ is an octahedral species, and should have only one fluorine environment due to the symmetry. $\ce{Br}$ has nuclear spin $I=3/2$ and therefore is unlikely to cause splitting due to rapid ...
5
votes
5answers
31k views

Why is the melting of ice a spontaneous reaction?

So here's my question: we know that melting of ice is an spontaneous reaction but is it spontaneous? We have to supply energy in the form heat for the reaction to take place.
1
vote
2answers
364 views

Computing pH of a buffer, and concentrations

You pour $50~\mathrm{mL}$ of a $0.0200~\mathrm{M}$ $\ce{HCOOH}$-solution to $150~\mathrm{mL}$ of a $0.0500~\mathrm{M}$ $\ce{HCOONa}$-solution. The $K_\mathrm{a}$ of $\ce{HCOOH}$ is $1.8 \times 10^{-4}$...
1
vote
1answer
754 views

Acid catalyzed hydrolysis of ester

During acid catalyzed hydrolysis of ester why does the carbonyl oxygen attack the $\ce{H^{+}}$ ? Why doesn't the alkoxy oxygen which is more electron rich and less electronegative not attack the $\ce{...
1
vote
1answer
2k views

What is the mechanism of trialkylborane oxidation with hydroperoxide?

This is the mechanism of trialkylborane. In this mechanism I can't understand why should the -OH group leave and the -R group enter in its place to form borate ester. Can someone please explain me ...
3
votes
1answer
4k views

How is it possible, that the hydrolysis of ethers proceed via a SN2 mechanism?

Ethers on hydrolysis with dilute $\ce{H2SO4}$ under pressure produce alcohols. This is basically a type of acidic cleavage of ethers by the SN2 mechanism. (source) There is inversion of ...
2
votes
2answers
7k views

Given the concentration and density of a sample, calculate moles of bleach?

Given the concentration of bleach ($6\%\,\mathrm{m/m}$), density of bleach ($1.07\,\mathrm{g\,mL^{-1}}$), and molar mass of bleach ($74.44\,\mathrm{g\,mol^{-1}}$) how many moles of bleach are in a $4....
7
votes
2answers
909 views

Way to detect lead in gasoline

Is there any way that i can detect lead in gasoline, not by sending of to a lab but to be able to do this by myself?
1
vote
1answer
53 views

Electrodeposition of Ni

How can one electrodeposit Nickel on a substrate using a liquid crystal template? substrate is Indium Tin Oxide coated plate and the template is cetyl trimethylammonium bromide(CTAB)+WATER+ETHANOL
0
votes
1answer
930 views

Which of these compounds does not liberate heat when water is added to it?

Which of these compounds does not liberate heat when water is added to it: $\ce{KNO_3}$, $\ce{NaOH}$, $\ce{CaO}$, $\ce{H_2SO_4}$, $\ce{Na}$. I know from experience that dropping sodium tablets into ...
4
votes
1answer
2k views

Why are esters meta directors? Can't the carbonyl donate electrons into the ring?

I'm having trouble understanding why an ester is a meta directing/deactivating group. I'm not talking about an ester with its oxygen bound to the ring, like an acylated phenol. I mean the R group is ...
1
vote
1answer
177 views

What ion remains in the largest concentration at equilibrium: 0.1 M H₃PO₄ and 0.2 M KOH?

Mix equal volumes of $0.1~\mathrm{M}$ $\ce{H3PO4}$ and $0.2~\mathrm{M}$ $\ce{KOH}$. What ion remains in the largest concentration at equilibrium? My approach: suppose we mix $1~\mathrm{L}$ of each ...
2
votes
1answer
2k views

Is an iron (II) sulphate solution supposed to turn cloudy when silver nitrate is added?

$\ce{AgNO3}$ is not suppose to cause a precipitation when mixed with $\ce{FeSO4}$, but the acidified solution turns slightly cloudy when $\ce{AgNO3}$ is added. Is this suppose to happen? solutions ...

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