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I intend to destroy (dissolving would be optimal) a few computer chips (NAND memory chips used eg. on SSDs to be precise).
Why? See foot note.
I am not a chemist, so of course I tried to research the topic a bit before actually attempting anything. I got to know that they are covered in a resin called CNE and that ... |
Having read the following was wondering something . :
$$ pk_{a} = \frac{[H^+][A^-]}{[HA]} $$
$$ HA <=> H^+ + A^- $$
$$pH = pk_{a} - log\frac{[A^-]}{[HA]} $$
This rmgd
$$ [A^-] = [salt] $$
when acid is weak .
Now my question is like this : take a beaker of CH3COOH . Now add CH3COONa . Now here using the a over f... |
Having read the following was wondering something:
$$\mathrm {p}K_\mathrm{a} = \frac{[\ce{H+}][\ce{A-}]}{[\ce{HA}]} $$
$$\ce{HA <=> H+ + A-}$$
$$\mathrm{pH = p}K\mathrm{_{a}} - \mathrm{log\frac{[\ce{A-}]}{[\ce{HA}]}} $$
This rmgd
$$ \mathrm{[\ce{A-}] = [salt] }$$
when acid is weak .
Now my question is like this... |
Having read the following was wondering something:
$$\mathrm {p}K_\mathrm{a} = -log\frac{[\ce{H+}][\ce{A-}]}{[\ce{HA}]} $$
$$\ce{HA <=> H+ + A-}$$
$$\mathrm{pH = p}K\mathrm{_{a}} - \mathrm{log\frac{[\ce{A-}]}{[\ce{HA}]}} $$
This rmgd
$$ \mathrm{[\ce{A-}] = [salt] }$$
when acid is weak .
Now my question is like ... |
How is the selective titration testing equation simplified? |
i need some guidance regarding the issue of solubility, as you can see in my question i have glycol and ether.
What factors play a role in the solubilization process between these two compounds?
I know that glyccol has polar character and intermolecular dipole-dipole forces, while ether (ethyl ether, i imagine) h... |
Explain the mechanism of glycerol solubility in ether.? |
Having read the following was wondering something:
$$\mathrm {p}K_\mathrm{a} = -\log\frac{[\ce{H+}][\ce{A-}]}{[\ce{HA}]} $$
$$\ce{HA <=> H+ + A-}$$
$$\mathrm{pH = p}K\mathrm{_{a}} - \mathrm{log\frac{[\ce{A-}]}{[\ce{HA}]}} $$
This rmgd
$$ \mathrm{[\ce{A-}] = [salt] }$$
when acid is weak.
Now my question is lik... |
I need some guidance regarding the issue of solubility, as you can see in my question i have glycerol and ether.
What factors play a role in the solubilization process between these two compounds?
I know that glycerol has polar character and intermolecular dipole-dipole forces, while ether (ethyl ether, i imagine... |
How would an electron identify the specific photons of a certain wavelength which are to be absorbed in a Hydrogen atom while creating an absorption spectrum? Well, I was thinking of it like this-
Way-01: The electron will absorb any electron coming towards it regardless of its wavelength and jump. Then if the wavel... |
How does an electron identify whether to absorb a photon of a certain wavelength or not in absorption spectrum? |
Having read the following was wondering something:
$$\mathrm {p}K_\mathrm{a} = -\log\frac{[\ce{H+}][\ce{A-}]}{[\ce{HA}]} $$
$$\ce{HA <=> H+ + A-}$$
$$\mathrm{pH = p}K\mathrm{_{a}} +\mathrm{log\frac{[\ce{A-}]}{[\ce{HA}]}} $$
This rmgd
$$ \mathrm{[\ce{A-}] = [salt] }$$
when acid is weak.
Now my question is like... |
How would an electron identify the specific photons of a certain wavelength which are to be absorbed in a Hydrogen atom while creating an absorption spectrum? Well, I was thinking of it like this-
Way-01: The electron will absorb any photon coming towards it regardless of its wavelength and jump. Then if the wavelen... |
> [OP..] How would an electron identify the specific photons of a certain wavelength which are to be absorbed in a Hydrogen atom while creating an absorption spectrum?
As discussed in the comments, this is an observed phenomenon. We can try to describe this observation in a way that we can make predictions, but that... |
Having read the following was wondering something:
$$\mathrm {p}K_\mathrm{a} = -\log\frac{[\ce{H+}]_\mathrm{eq}[\ce{A-}]_\mathrm{eq}}{[\ce{HA}]_\mathrm{eq}} $$
$$\ce{HA <=> H+ + A-}$$
$$\mathrm{pH = p}K\mathrm{_{a}} +\mathrm{log\frac{[\ce{A-}]}{[\ce{HA}]}} $$
This rmgd
$$ \mathrm{[\ce{A-}] = [salt] }$$
when acid ... |
From my understanding, the compressibility factor is defined by
$$Z=\frac{pv}{RT}=\frac{p\bar{v}}{\bar{R}T}$$
It can also be defined by the ratio of the real molar volume of a gas to the ideal molar volume of a gas at the same temperature and pressure. Essentially it corrects for the deviation of a real gas from... |
I was doing an experiment in chemistry class involving titrations. I would heat up different samples of vinegar and titrate them using NaOH. The trend that I found was how has temperature increase, the pH of the endpoint decreases. Can someone explain this to me please? |
Why does the pH of the endpoint decrease when temperature of the titration is increased? |
If you wanted to increase the pH of a weak acid by 1, how many times should you need to dilute it? |
When considering the electrical conductivity of metal oxides, they will conduct better if the metals orbitals can reach each other to overlap. Whether this can happen is contributed to by a couple of things such as Z-eff charge (electronegativity), the anion, oxidation state etc. We're told that one of those propertie... |
Why do 4d and 5d metals have more orbital overlap than 3d because of size? |
I have some water-soluble crystalbond that is attached to silicon and, because of some overheating (to about 150 Celcius) during a final processing step, the crystalbond seems to have charred (white/grayish colour, see photo at the bottom) and is no longer dissolvable in water. Since this silicon is important and canno... |
I'm really interested in the [Fischer-Tropsch][1] [gas-to-liquids][2] (GTL) process. A lot of people are using wood or other biomass feedstock to make syngas on small scales (farms, shops, etc.).
Practically, what would be required to build a small scale GTL reactor to run a Fischer-Tropsch process on a small scale... |
Small scale gas-to-liquids via Fischer-Tropsch — is it even possible? |
Is there a way to exactly calculate the quantity of hydrogen or oxygen in a water electrolysis? I am thinking of a plain and simple electrolysis like an anode and cathode in salted water separating oxygen and hydrogen.
I am looking for the relation between the amounts of hydrogen $n(\ce{H2})$ or oxygen $n(\ce{O2})$ ... |
How much hydrogen or oxygen will be produced in the electrolysis of water? |
What organic molecules have a relatively small work function, preferably in the visible spectrum? Polycyclic aromatic hydrocarbons are in the low UV spectrum, making it unsuitable for the photocathode requirement. |
If I have an unsymmetrical alkene like the one in the picture with Br2 (Anti reaction), [![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/xCVoi.png
I need the product with stereochemistry, How do i do it with a simple rule? since it's an anti reaction, does that mean that I just need to p... |
Stereochemistry of the product of an alkene + Br2? |
If I have an unsymmetrical alkene like the one in the picture with bromine (Anti reaction), [![Reactants of prop-2-en-oic acid with bromine][1]][1]
[1]: https://i.stack.imgur.com/xCVoi.png
I need the product with stereochemistry, how do I determine it with a simple rule? If it's an anti reaction, does that me... |
Stereochemistry of the product of an alkene with bromine? |
I can draw two possible Lewis structures for $\ce{PO2F2-}$ anion:
[![Lewis structures of difluorophosphate][1]][1]
What is the correct structure and why is the other one wrong?
[1]: https://i.stack.imgur.com/Cinyl.png |
What is the correct Lewis structure of difluorophosphate? |
Is there a a simple rule for determining the stereochemistry for the product of a reaction between an unsymmetrical alkene like (2*E*)-but-2-enoic acid and bromine (*anti* reaction)?
[![Reaction between crotonic acid and bromine][1]][1]
If it's an *anti* reaction, does that mean that I just need to put each bromi... |
I've read about photoelectric cells, and most of the sources say that Potassium and Cesium can be used as electrodes in the same. But why not Rubidium?
The abundant isotope of Rb (72.2%) is not radioactive either, and is actually quite stable.
The ionization energy of Rb lies in between that of Cs and K, so its ... |
Complexes of type $\ce{MA3B3}$ have two geometrical isomers, namely:
1. *fac*-isomer
2. *mer*-isomer
If we look closely at the *mer*-isomer, it has a plane of symmetry, so it is optically inactive.
But the *fac*-isomer has no plane of symmetry. Still, it is optically inactive, why?
Being a 12th grader, I won... |
I am coming from a chemical background and currently work in the field of vibrational spectroscopy. When I talk to fellow physicists or chemists I always encounter the same question. "Why are the vibrational modes of methyl- and methylenegroups are called r and d modes".
Does this have a group theory background? ... |
When I mix whey protein powder into warm porridge (that I cooked in the microwave), the thick porridge becomes much less thick.
I searched this, and I found several forum threads discussing this too so it seems to be a common phenomenon. Happens when cooking porridge on the hob too, not just from mixing protein in a... |
Why does whey protein powder make porridge much less viscous? |
**It probably isn't practical to do Fischer-Tropsch on a small scale**
Gasification of biomass is easy. And produces syngas, a mixture of carbon dioxide, carbon monoxide, hydrogen and other compounds.
But the Fischer-Tropsch process to convert that mixture into useful liquids (like diesel) is not easy. The proces... |
I would like to know how you could increase the voltage in zinc and copper galvanic cell:
Zn(s) +Cu2+ → Zn2+ +Cu(s)
I know that temperature and surface area is a factor that affects the voltage, but I would like to specifically know about how concentration changes the voltage.
If I want to increase the voltage... |
does increasing one of the electrolytes in a galvanic cell increase the voltage? |
I'm really interested in the [Fischer–Tropsch][1] [gas-to-liquids][2] (GTL) process. A lot of people are using wood or other biomass feedstock to make syngas on small scales (farms, shops, etc.).
Practically, what would be required to build a small scale GTL reactor to run a Fischer–Tropsch process on a small scale... |
Small scale gas-to-liquids via Fischer–Tropsch — is it even possible? |
Does cinnabar react with bromine and iodine to form elemental sulphur? This reaction was described in "Explorations in the history of science and technology in China" but I have doubts...[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/sZFgH.png |
Does cinnabar react with iodine? |
I would like to know how you could increase the voltage in zinc and copper galvanic cell:
$$\ce{Zn(s) + Cu^2+ → Zn^2+ + Cu(s)}$$
I know that temperature and surface area is a factor that affects the voltage, but I would like to specifically know about how concentration changes the voltage.
If I want to increase... |
Does increasing one of the electrolytes in a galvanic cell increase the voltage? |
When I mix whey protein powder into warm porridge (that I cooked in the microwave), the thick porridge becomes much less thick.
I searched this, and I found several forum threads discussing this too so it seems to be a common phenomenon. Happens when cooking porridge on the hob too, not just from mixing protein in a... |
I understand the mechanism behind the cathode's increasing mass in many batteries. As the cathode receives electrons, ions are reduced to form atoms. In short, more electrons equals more mass in the cathode. what I was wondering is whether or not there are batteries where the cathode does not increase in mass for whate... |
Do the cathodes of all batteries increase in mass as the battery is used? |
Standard electrode potentials are reported for materials that are not usable as actual electrodes in water because they react spontaneously and rapidly. https://www.engineeringtoolbox.com/electrode-potential-d_482.html
Some metals, like zinc, are useful as cell electrodes if pure, but if not so pure, exhibit cathodi... |
I know that the decaffeination process is not perfect and that it leaves some caffeine. I've looked online and there was a company in 2009 that offered **caffeine test strips** but they seem to be no longer offered.
Another approach would be to use a GCMS, but used GCMS devices are expensive and it takes alot of eff... |
How can I find out how much caffeine is in my decaf tea and coffee? |
I have some water-soluble crystalbond that is attached to silicon and, because of some overheating (to about 150 Celcius) during a final processing step, the crystalbond seems to have charred (white/grayish colour, see photo at the bottom) and is no longer dissolvable in water. Since this silicon is important and canno... |
1. When adding calcium hydroxide to water and corn for nixtamalization, does the heat of the water have any effect on the "activation" of the calcium hydroxide? How so?
1a. Specifically, what causes the change in water color (from clear to yellow)?
2. Does the ratio of calcium hydroxide to water have any effect ... |
I wondered if the electron lone pairs on the oxygen atoms also counted as pi electrons since resonance structures exist where these lone pairs can be delocalised over the molecule? If so how would this correspond to using them to find the length of the conjugated system because wouldn’t that give extra length where the... |
I am asking for help because I couldn't find the answer even on the Internet ?
Let's say we have :
- a **gas 1** moving inside a pipe (we don't know the geometry) at **mass flow rate $Q_1$ and temperature $T_1$**
We inject a gas 2 at some point inside the gas 1 :
- **gas 2** is injected at **mass fow rate $Q_2$... |
What organic molecules have a relatively small work function, preferably in the visible spectrum? Polycyclic aromatic hydrocarbons are in the low UV spectrum, making it unsuitable for the photocathode requirement. A work function in the green-cyan spectrum, or anything below3 eV is the main focus. Efficiency, thermal s... |
The essence of what's going on is this:
Your equation, $dG = Vdp -SdT$, is correct, but has restrictions you don't realize. Specifically, it applies only to systems that are (a) closed (so no adding or subtracting material), (b) have only a single-component* (so no mixing, phase changes, or chemical reactions) and (... |
In valence bond theory, I suppose that electrons in say, 2px and 2py have the same energy because of the same structure of orbitals. But what about 3dxy and 3dz^2? Do they also have the same energy? I would say, no for the difference in their shape. But I am not quite sure since they are in the same subshell. could any... |
Please pardon my chemistry ignorance! I actually have done a lot research on these specific topics, but can't find anything definitive--anywhere!
1. When adding calcium hydroxide to water and corn for nixtamalization, does the heat of the water have any effect on the "activation" of the calcium hydroxide (specific ... |
Please pardon my chemistry ignorance! I actually have done a lot research on these specific topics, but can't find anything definitive--anywhere!
1. When adding calcium hydroxide to water and corn for [nixtamalization][1], does the heat of the water have any effect on the "activation" of the calcium hydroxide (spec... |
I am asking for help because I couldn't find the answer even on the Internet ?
Let's say we have :
- a gas 1 moving inside a pipe (we don't know the geometry) at mass flow rate $Q_1$ and temperature $T_1$
We inject a gas 2 at some point inside the gas 1 :
- gas 2is injected at mass fow rate $Q_2$ and at tempera... |
Let's say we have a gas **1** moving inside a pipe (we don't know the geometry) at mass flow rate $Q_1$ and temperature $T_1.$ We inject a gas **2** at some point inside the pipe with gas **1** at mass flow rate $Q_2$ and at temperature $T_2.$
We know that the resulting mixture is moving at the mass flow rate $Q_\m... |
The essence of what's going on is this:
Your equation, $dG = Vdp -SdT$, is correct, but has restrictions you don't realize. Specifically, it applies only to systems that are (a) closed (so no adding or subtracting material), (b) have only a single component* (so no mixing, phase changes, or chemical reactions) and (... |
Sodium hydroxide is generally prepared
commercially by the electrolysis of sodium
chloride in Castner-Kellner cell. A brine
solution is electrolyzed using a mercury
cathode and a carbon anode. Sodium metal
discharged at the cathode combines with
mercury to form sodium amalgam.
My question is, why sodium ion disc... |
[This filter](https://www.aquasanaeurope.com/products/aquasana-powered-water-filter-countertop-pitcher-in-white.html) rates a 3 month lifespan with 1210 liter capacity, but I expect to filter only 300 liters in 3 months. Is it still expired after 3 months - if so, why? What degrades a filter while it's unused? |
Do water filters expire even if underused? |
Ive used zinc sulfate and copper sulfate as the solutions, and used zinc and copper electrodes.
For salt bridge, I took lithium, potassium, calcium, sodium and zinc nitrates. The results are as below:
Zinc Nitrate: 1.071V
Potassium Nitrate: 1.071V
Lithium Nitrate: 1.081V
Calcium Nitrate: 1.069V
Sodium N... |
Will changing the salt in the salt bridge change the voltage produced in a galvanic cell? |
Of course it is a pipe and it has a infinite volume hypotactically,
To use ideal gas equations is a bit tricky with *mass flow rate* need to convert to *molar flow rate* of each gas thus need to divide by $\ce{M_w}$ molecular weight respective to each gas.
Consider $\ce{1}$ time unit where inside of pipe gets
... |
I have used zinc sulfate and copper sulfate as the solutions, and used zinc and copper electrodes.
For salt bridge I took lithium, potassium, calcium, sodium and zinc nitrates. The results are as below:
$$
\begin{array}{lr}
\hline
\text{Compound} & E_\mathrm{cell}/\pu{V} \\
\hline
\ce{LiNO3} & 1.081 \\
\ce... |
Atomic nucleus-The atomic nucleus is the small dense region consisting of protons and neutrons at the center of an atom discovered in 1911 by EARNEST RUTHERFORD. Atoms are made up of a positively charged nucleus surrounded by a cloud of negatively charged atoms. Nuclei are very dense and extremely small. They contain m... |
What is the difference between atom and nucleus? |
I learnt about how ocean acidification can be described in terms of equilibrium. This is summarized in the textbook diagram below:
[![enter image description here][1]][1]
However, this diagram doesn't explain to me why the shells should be softening. As more CO2 is put into the atmosphere, this will increase $\ce... |
Why are shells softening in the ocean? |
Atomic nucleus-The atomic nucleus is the small dense region consisting of protons and neutrons at the center of an atom discovered in 1911 by EARNEST RUTHERFORD. Atoms are made up of a positively charged nucleus surrounded by a cloud of negatively charged atoms. Nuclei are very dense and extremely small. They contain m... |
I'm interested in the denaturation of proteins by alcohols, specifically by ethanol.
I have devised a simple experiment in which I inject solutions of ethanol (of variable concentrations) into solutions of egg albumen (containing proteins such as conalbumin). **I have observed a marked pH change in solution after i... |
Why does denaturation of albumen protein cause pH of solution to increase? |
I have a very expensive custom made automotive aluminum radiator that has had a mouse or mice nesting inside the top tank. I have removed most of the nesting material through the top inlet but I want to clear the radiator tubes that may be plugged up with the nesting material (looks like cotton of some sort) and be su... |
16 g of dioxygen contains 16 g of oxygen atoms. To find out how much carbon dioxide is produced, you can either use a realistic description of the reaction, or you can go atom by atom. Either path gives the same solution, but the one chosen by the textbook is not modern chemistry, and makes some of us angry or sad.
... |
What does the pKb (or $K_b$) of a strong acid mean?
For instance [this link][1] reports the Kb of HI, an extremely strong acid. Are they reporting the reaction constant of the reaction:
$HI + H_2O \implies H_2I^+ + OH^- $
Is the $K_b$ for the equation?
That reaction seems so bizarre; it seems like the pro... |
pKb of a strong acid? |
I am aware of the regioselectivity of silyl enol ether formation at an unsymmetrical ketone under 'thermodynamic conditions'.
Does this selectivity extend to systems containing more than one ketone group?
In other words, if some starting material were to contain two ketone groups, under 'thermodynamic conditions'... |
You might look up the decomposition of hydrogen peroxide, $\ce{H2O2}$. The 3% solution sold as antiseptic should be safe to use at home, as would be some readily available catalysts and inhibitors.
Horseradish might be used for a catalyst... but don't eat it in the lab.
To measure speed of reaction, measure gas e... |
What is the different in stereochemistry between the product of cis alkene with mCPBA and trans alkene with mCPBA, I drew the products, they do look different but the configurations are the exact same, does that mean that they give the same products?
[![enter image description here][1]][1]
[1]: https://i.stac... |
Trans/Cis Alkene with mCPBA products? |
When I look up the definition of solute and solvent, the definition by the Oxford English Dictionary is
solute
/ˈsɒljuːt,sɒˈljuːt/
noun
the ***minor*** component in a solution, dissolved in the solvent.
What does minor imply here? Does it classify them as solute and solvent as per mass/vo... |
I am not 100% sure if this is the right place to ask, but please point me in the right direction if not.
I am designing a conductivity meter, and when it comes to displaying the results in mS/cm or µS/cm, I also need to convert to EC. The first place I found was [THIS][1] website which seems great as it has all the... |
Is it possible to decompose cinnabar into Hg and S instead of Hg+SO2 by roasting/heating? What conditions have to be satisfied? |
Is it possible to decompose cinnabar into $\ce{Hg}$ and $\ce{S}$ instead of $\ce{Hg + SO2}$ with roasting and heating. What conditions need to be satisfied in the new method?
|
Cinnabar decomposition by heating optional method? |
I am not 100% sure if this is the right place to ask, but please point me in the right direction if not.
I am designing a conductivity meter, and when it comes to displaying the results in mS/cm or µS/cm, I also need to convert to EC. The first place I found was [THIS][1] website which seems great as it has all the... |
I am not 100% sure if this is the right place to ask, but please point me in the right direction if not.
I am designing a conductivity meter, and when it comes to displaying the results in mS/cm or µS/cm, I also need to convert to EC. The first place I found was [THIS][1] website which seems great as it has all the... |
how to increase pH by 1? |
I need to prepare the 1M solution of sodium crotonate, however, I don't have one in lab, but I do have sodium hydroxide and crotonic acid.
Thus, I calculated that for 100 ml of 1M solution I need: ~4g of NaOH and ~8.6g of crotonic acid. After preparation of solution (approx 80 ml of DI water to dissolve the crotoni... |
What pH value of 1M sodium crotonate solution supposed to be? |
how to increase pH of a strong acid by 1? |
If you wanted to increase the pH of a weak acid by 1, how many times should you need to dilute it? |
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