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Does this two product are the same in terms of grade? |
My friend is installing copper pipes in his house, which is going to be in a humid area, and he says that copper will only be oxidized by the air and the excess water vapor in the humid air won't affect it. However, it is to my understanding that since water vapor is $\ce{H2O}$, which contains oxygen, there will be mor... |
I spent a while trying to figure out which stackexchange site in which to post this question, forgive me if I got it wrong.
A [number][1] of scholarly articles indicate that concrete can leach calcium compounds under the right conditions. Could they ever wick upwards against gravity through dry or water-saturated so... |
Can compounds found in concrete leach into soil against gravity? |
I am refluxing HBr with 1,6-hexanediol for 16 hours at 80 degrees in toluene solvent. How can I be sure that more than 90% of the product is brominated only at one terminal? If double brominated product is in more than 10% of total yield, then product mixture will be useless for me. |
The benzyloxycarbonyl group (CBZ) is widely used to protect amines, especially in
aminoacid chemistry. A procedure to synthesise the CBZ derivative of glycine from glycine and benzyl chloroformate is given in the description below.
Glycine ($0.1~\mathrm{mol}$) was dissolved in aqueous sodium hydroxide ($50~\mathr... |
The benzyloxycarbonyl group (CBZ) is widely used to protect amines, especially in aminoacid chemistry. A procedure to synthesise the CBZ derivative of glycine from glycine and benzyl chloroformate is given in the description below.
> Glycine ($0.1~\mathrm{mol}$) was dissolved in aqueous sodium hydroxide ($50~\mathr... |
I stumbled-upon this compound:
CC=C1C(C)CCC1(C)
![CC=C1C(C)CCC1(C)][1]
and I'm wondering how to determine the configuration of the double bond. Is it *E* or *Z*? How do I decide on the priorities when the substituents can only differ in the configurations on the chiral centers? I googled around and searche... |
How to determine priorities for this compound accoring to the Cahn-Ingold-Prelog rules? |
Formula for calculating age by using carbon-14 (source: [HowStuffWorks](http://science.howstuffworks.com/environmental/earth/geology/carbon-142.htm))
$$
t = \frac{\ln (N_f/N_o)}{-0.693}t_{1/2}
$$
The page doesn't explain what the $-0.693$ represents. What is $-0.693$?
Secondly, it says that $N_o$ is the original l... |
How to determine priorities for this compound according to the Cahn-Ingold-Prelog rules? |
Is it wise to use ECPs on light atoms for electronic structure calculations? |
Does phenol undergoes friedel–crafts reaction or it reacts with lewis acid like Aniline does? |
Is element 111 considered to act as an eka-aurum?
Being under the same column of group 11, which usually provides enough evidence for correlation of properties for an eka-element, would this element have the similar properties such as conductivity or inertness with gold?
With the understanding of the correlation be... |
I am refluxing $\ce{HBr}$ with 1,6-hexanediol for 16 hours at 80 degrees in toluene solvent. How can I be sure that more than 90% of the product is brominated only at one terminal? If double brominated product is in more than 10% of total yield, then product mixture will be useless for me. |
I am refluxing $\ce{HBr}$ with 1,6-hexanediol for 16 hours at 80 °C in toluene. How can I be sure that more than 90% of the product is brominated only at one terminal? If the amount of double brominated product is in more than 10% of the total yield, then the product mixture will be useless for me. |
Chemistry help - How much COCl2 in grams is in the equilibrium mixture? |
Large elements of my answer is drawn from my own notes that I use for teaching General Chemistry II.
-----------
**What is −0.693?**
Radioactive decay processes follow first-order kinetics. A first-order reaction is one where the rate depends **only** on the concentration of one of the reactants raised to the... |
Can Calcium chloride be effectively used as a desiccant to absorb both heat and moisture? |
I'm stuck on the last question of my homework and I really need some help!
> How much $\ce{COCl2}$ grams is in the equilibrium mixture?
> Consider the reaction:
$$\ce{CO(g) + Cl2(g) <=> COCl2(g)}$$
$K_\mathrm{eq}= 2.9\cdot 10^{10}$ at 25 °C
A 5.69 L flask containing an equilibrium reaction mixture has $[\ce... |
How to calculate the mass of phosgene in the equilibrium mixture of carbon dioxide and dichloride? |
Can calcium chloride be effectively used as a desiccant to absorb both heat and moisture? |
I am having a problem wrapping my mind around the idea that in $230\:\mathrm{mL}$ of $0.615\:\mathrm{M}$ $\ce{KCl}$ there is $0.141\:\mathrm{mol}$ of $\ce{Cl^-}$ ions. I guess I still do not understand moles.
Is this calculation saying that there $0.141\:\mathrm{mol}$ of $\ce{K}$ and $\ce{Cl}$ in one mole of $\ce{KC... |
I've been struggling with this for a while, and I can't seem to solve the problem. Alcohol is made in the fermentation process in beer:
"Sugars formed during mashing (maltose and maltotriose) will undergo hydrolysis and form multiple molecules of the simple sugar glucose. This glucose will then be fermented by the y... |
The photoelectron spectrum of krypton is shown below.![enter image description here][1]
[1]: https://i.stack.imgur.com/7KCra.png
(where the x-axis is in electron volts (eV))\
Since both the 3p and 3d shells are more than half full, based on Hund's rules the lowest-energy level is the one with the largest J... |
The photoelectron spectrum of krypton is shown below.![enter image description here][1]
[1]: https://i.stack.imgur.com/7KCra.png
(where the x-axis is in electron volts (eV))\
Since both the $3p$ and $3d$ shells are more than half full, based on Hund's rules the lowest-energy level is the one with the large... |
As far as I understand, there has been very limited experimental investigation of the chemistry of roentgenium (Z=111), if at all, simply due to the fact that so few atoms have been produced and they decay so quickly. It is possible to do some chemistry with even single atoms in seconds, but as you might expect it's an... |
As far as I understand, there has been very limited experimental investigation of the properties of roentgenium (Z=111), if at all, simply due to the fact that so few atoms have been produced and they decay so quickly. It is possible to do some chemistry with even single atoms in seconds, but as you might expect it's a... |
As far as I understand, there has been very limited experimental investigation of the properties of roentgenium (Z=111), if at all, simply due to the fact that so few atoms have been produced and they decay so quickly. It is possible to do some chemistry with even single atoms in seconds, but as you might expect it's a... |
I'm familiar with the fact that theoretical formulae are based on already known theory and are very frequently simplified (some equations don't include interactions between molecules for example) while the purpose of empirical equations (like polynomial equations) is just to follow experimental measurements even if it ... |
Can anyone explain why my textbook only gives the following resonance structures?
> Write the important resonance structures for each of the following:
![question][1]
---
![answer][2]
I also put two resonance case where the double bond electrons are moved on the individual carbon atoms.
[1]: https... |
![enter image description here][1]
What will be the major product of this elimination reaction?
The exocyclic product has more substituent groups on the alkene which should make it more stable but I have heard that exocyclic alkenes are less stable than their endocyclic counterparts. Why is this the case and is i... |
> What will be the major product of this elimination reaction?
In the acid-catalyzed dehydration of 1-methylcyclohexanol, both 1-methylcyclohexene and methylenecyclohexane are formed in *ca*. an 85:15 ratio. In your example we have two more substituents on the exocyclic double bond which will serve to further stabi... |
# Yes.
The battery bounce test *kind of* works. You can tell whether the battery still has a charge greater than 90%, but bounce hight levels off at about 50% and doesn't go higher. This means that it is not clear whether the battery is completely discharged when you observe a bounce.
# Why?
[Steingart *et al.... |
From what point of view? Environmental? Industrial? Practical?
In Europe (I live in Italy) we use methane a lot, both for automotive and for house heating/cooking.
From the environmental point ov view, $\ce{CH4}$ is one of the best choices (together with LPG). When burnt (both in thermodynamics engines and in fre... |
> Arrange these compounds: $\ce{CO2}$, $\ce{CH3OH}$, $\ce{RbF}$, $\ce{CH3Br}$ in order of increasing boiling points.
I think I should consider the forces between them, that is:
* $\ce{CO2}$: dispersion forces
* $\ce{RbF}$: dispersion and ionic forces
* $\ce{CH3OH}$: Dipole-dipole interactions, Hydrogen bonding... |
- Name of the compund: **Dimethyl nitroxide**
- Lewis structure:
![enter image description here][1]
- [Reference][2]
[1]: https://i.stack.imgur.com/nez1q.png
[2]: http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?publicId=1860-5397-9-181 |
I'm attempting to write the balanced equation of the combination of Lithium metal and Fluorine gas. I understand that this will produce an Ionic solid because it is a reaction of a metal and a nonmetal. However, I'm confused with the fluoride ion having a charge of -1 and fluorine only occurring as a diatomic molecule ... |
Is F2 two fluoride ions or just one? |
- Name of the compund: **Dimethyl nitroxide**
- Lewis structure:
![enter image description here][1]
- [Reference][2]
- Full Lewis structure:
H
..
H:C:H
.. ..
:N : O .
.. ..
H:C:H
..
... |
Most cheap items (from China mostly) have a strong tangy odor to the plastics (or some resin, but I can mostly smell it on plastics). The smell is always consistent over a broad range or products and I get it for at least a decade. So I do not believe this is a one-off thing and I bet most people have experienced it. T... |
- Name of the compund: **Dimethyl nitroxide**
- Lewis structure:
![enter image description here][1]
- [Reference][2]
- Full Lewis structure:
![enter image description here][3]
[1]: https://i.stack.imgur.com/nez1q.png
[2]: http://www.beilstein-journals.org/bjoc/single/articleFullText.htm?public... |
I'm attempting to write the balanced equation of the combination of lithium metal and fluorine gas. I understand that this will produce an Ionic solid because it is a reaction of a metal and a nonmetal. However, I'm confused with the fluoride ion having a charge of -1 and fluorine only occurring as a diatomic molecule ... |
For school, my teacher asked what the proper procedure/reaction would be to add a polyvinyl alcohol chain onto a polyethylene chain. Can anyone help? I'll provide additional information if needed. |
In one of my MCQ questions, there was a statement saying all group 2 elements form covalent hydroxides. I know it is incorrect.I know that BeH2 is a covalent hydride. What about the rest?Are all of them metallic hydroxides? Is it true that metallic hydrides produce the hydroxide and give off H2 with water?
|
In one of my MCQ questions, there was a statement saying all group 2 elements form covalent hydroxides. I know it is incorrect. I know that $\ce{BeH2}$ is a covalent hydride. What about the rest? Are all of them metallic hydroxides? Is it true that metallic hydrides produce the hydroxide and give off $\ce{H2}$ with wat... |
I'm attempting to write the balanced equation of the combination of lithium metal and fluorine gas. I understand that this will produce an ionic solid because it is a reaction of a metal and a nonmetal. However, I'm confused with the fluoride ion having a charge of -1 and fluorine only occurring as a diatomic molecule ... |
I am refluxing $\ce{HBr}$ with 1,6-hexanediol for $16\:\mathrm{hours}$ at $80°\mathrm{C}$ in toluene. How can I be sure that more than $90\%$ of the product is brominated only at one terminal? If the amount of double brominated product is in more than $10\%$ of the total yield, then the product mixture will be useless ... |
Here is the unbalanced equation.
$$\ce{Fe(OH)2(s) +O_2(g)\rightarrow Fe(OH)3(s)}$$
Therefore, one half reaction is
$$\ce{Fe(OH)2(s) +O2(g)\rightarrow Fe(OH)3(s)}$$
and the other half reaction is
$$\ce{O2(g)\rightarrow 2H2O\:(l)}$$
My question, how are we justified in making the latter half reactio... |
Would really be good tip know. Just getting interested in this stuff.
I tried to crystallize a leaf. Failed.
What materials other than table salt can be crystallized?
Any guidance and examples would be great! |
What things form crystals? |
- Name of the compund: **Dimethyl nitroxide**
- Full Lewis structure:
![enter image description here][3]
- Further information of related Lewis structures and how this knowledge is applied on real top science, I recomender seeing this [reference:][2] Moreira, G.; Charles, L.; Major, M.; Vacandio, F.; Guilla... |
- Name of the compund: **Dimethyl nitroxide**
- Full Lewis structure:
![enter image description here][3]
- Further information of related Lewis structures and how this knowledge is applied on real top science, I recommend seeing this [reference:][2] Moreira, G.; Charles, L.; Major, M.; Vacandio, F.; Guillan... |
In vogel's organic book, they have mentioned that in lund bjerrum method of purification of ethanol, magnesium is added which forms ethanolate. But they said to activate the magnesium first by iodine.
Why is the activation needed and how exactly this activation process works in the activation of magnesium? |
There is a quite extensive chapter about hydrogen and its compounds in [Holleman and Wibereg's book "Inorganic Chemistry"][1]. As I only have the german version, I will briefly summarise what I read.
You are of course right, hydrogen forms salt-like structures with alkaline and earth alkaline elements, except for be... |
In one of my MCQ questions, there was a statement saying all group 2 elements form covalent hydroxides. I know it is incorrect. I know that $\ce{BeH2}$ is a covalent hydride. What about the rest? Are all of them metallic hydrides? Is it true that metallic hydrides produce the hydroxide and give off $\ce{H2}$ with water... |
What is the bonding type in hydrides of group 2 elements? |
*Let me try to talk you out of it ;-)*
The precious metals in a catalytic converter sit in a honeycomb ceramic that contains a lot of synthetic Cordierite. This material isn't only heat-resistant, but also quite hard.
Industrial recycling of catalytic converters typically starts with
1. dismantling (decannin... |
In Vogel's organic book, they have mentioned that in the Lund and Bjerrum method of purification of ethanol, magnesium is added, which forms ethanolate. But they said to activate the magnesium first by iodine.
Why is the activation needed and how exactly does this activation process work in the activation of magnes... |
I completed a titration of Ammonium Acetate buffer solution and to it I added 2M Hydrochloric Acid. I measured the initial pH of the buffer solution before any acid was added and I used methyl orange as an indicator which has a pKA value of 3. My independant variable was the temperature of the buffer. I was just wonder... |
I completed a titration of Ammonium Acetate buffer solution and to it I added 2M Hydrochloric Acid.
I measured the initial pH of the buffer solution before any acid was added and I used methyl orange as an indicator which has a pKA value of 3.
My independent variable was the temperature of the buffer.
I was j... |
![enter image description here][1]
What will be the major product of this elimination reaction?
The exocyclic product has more substituent groups on the alkene which should make it more stable but I have heard that exocyclic alkenes are less stable than their endocyclic counterparts. Why is this the case and is i... |
Would really be good to know. Just getting interested in this stuff.
People are saying I should crystallize salt, for example. What things could I do instead of salt with and still get a Crystal from? |
In one of our slides, the professor has written
> $ \Delta E_{sys} = -\Delta e_{sur}$
Where $E_{sys}$ symbolizes the energy of a given system, and $e_{sur}$ symbolizes the energy of the surroundings of that system.
On a few occasions, she's used both the upper, and the lower, case literal of a single letter ... |
Why does my professor use both the upper, and the lower, case literal of a letter to symbolize the same concept? |
Problem: 70 grams of pure, hydrated $MgSO_4$ is dissolved in 90 grams of $H_2O$. If the mole fraction of the solute is 0.039, find the molecular formula of the solute.$$$$
My flawed attempt at a solution:$$$$
Let the solute be $MgSO_4.xH_2O$<br>
In 70 grams, the number of moles of the solute is $\dfrac{70}{120+18x}$... |
According to Wikipedia,
> ... the definition of the gram is not (as of 2011) mathematically tied to that of the atomic mass unit
Why did we change that? |
Why is the gram no longer a function of the atomic mass number? |
> Problem: 70 grams of pure, hydrated $\ce{MgSO_4}$ is dissolved in 90
> grams of $\ce{H_2O}$. If the mole fraction of the solute is 0.039,
> find the molecular formula of the solute.
My flawed attempt at a solution:
Let the solute be $\ce{MgSO_4.xH_2O}$<br>
In 70 grams, the number of moles of the solute is $\... |
In my notes, I've used phrases such as 'atom, particle, or molecule' more often than I'd like. For example, Wikipedia defines atomic mass as
> the mass of an atomic particle, sub-atomic particle, or molecule.
I remember concise definitions more easily, so a single term for 'molecules and molecular constituents... |
Is there a term that denotes 'molecules and molecular constituents'? |
Why do sp2 carbons tend to prefer eclipsed conformations whereas sp3 carbons prefer anti-periplanar? |
**Reasoning**: My guess would have to be that it has to do with the strength of the intermolecular forces between each molecules. Take for example molecular compounds that have a very low molar mass like **CO** and **CH<sub>4</sub>**. Both of theses molecules have a very small molar mass, a very low london dispersion f... |
How to determine if a compound is likely to become a crystalline solid at room temperature? |
According to WebElements, of the Noble Gases, [$\ce{He}$][1], [$\ce{Ne}$][2] and [$\ce{Ar}$][3] do not react with any of the halogens; however:
- [$\ce{KrF2}$][4] can be synthesised at low temperatures.
- [Xenon][5] can react with fluorine to produce $\ce{XeF2}$, $\ce{XeF4}$ and $\ce{XeF6}$
- [Radon][6] can react ... |
The mer-people demand cooked food. They don't want to go on land to make it.
Is there a chemical reaction they could use which would create enough heat to cook their food underwater in a safe manner? |
Is there a chemical reaction which could give off enough heat underwater to cook something? |
In my notes, I've used phrases such as 'atom, particle, or molecule' more often than I'd like. For example, Wikipedia defines atomic mass as
> the mass of an atomic particle, sub-atomic particle, or molecule.
I remember concise definitions more easily, so a single word for 'molecules and molecular constituents... |
**Reasoning**: My guess would have to be that it has to do with the strength of the intermolecular forces between each molecules. Take for example, molecular compounds that have a very low molar mass like **$\ce{CO}$** and **$\ce{CH4}$**. Both of theses molecules have a very small molar mass, a very low London dispersi... |
**Reasoning**: My guess would have to be that it has to do with the strength of the intermolecular forces between each molecules. Take for example, molecular compounds that have a very low molar mass like **$\ce{CO}$** and **$\ce{CH4}$**. Both of theses molecules have a very small molar mass, a very low London dispersi... |
Interesting prompt!
There are plenty of reactions which could be performed underwater to release a large amount of energy. In fact, many substances react vigorously with water itself. You may have heard about how alkali metals such as sodium are not compatible with water, and there's [a good reason for it!](https://... |
Interesting prompt!
There are plenty of reactions which could be performed underwater to release a large amount of energy. In fact, many substances react vigorously with water itself. You may have heard about how alkali metals such as sodium are not compatible with water, and there's [a good reason for it!](https://... |
Methyl orange changes colors depending on the acidity or basicity of the solution. But I have read that it forms complexes with certain ions. Can anybody suggest any resource regarding the coordination complex-formation chemistry of methyl orange? |
How to determine if a compound is likely to become a solid at room temperature? |
Alright, let's take this one step at a time.
First of all, you want to determine a molecular formula, and among your known data you have a mole fraction. This suggests it's a good idea to work with moles to solve the problem. As such, the first step is to convert the amount of water added and magnesium sulfate hydra... |
Alright, let's take this one step at a time.
First of all, you want to determine a molecular formula, and among your known data you have a mole fraction. This suggests it's a good idea to work with moles to solve the problem. As such, the first step is to convert the amount of water added and magnesium sulfate hydra... |
> I remember using both 95% ethanol and absolute ethanol quite a few times. You'd need absolute ethanol for a reaction that would fail if water was present, such as a Grignard reaction. I can't remember whether the absolute ethanol was in an ordinary bottle or the type with a rubber septum (where you keep the liquid un... |
- Name of the compund: **Dimethyl nitroxide**
- Full Lewis structure:
![enter image description here][3]
- The properly way to determine the Lewis structure, based on this example, is:
1. Total valence electrons: $4\cdot2 + 5 + 6 + 1\cdot6 = 25$
2. Total electrons needed for octets/doublets: $8\cdot4+2\... |
>First, why would one use ethanol for a Grignard reaction? If a Grignard is destroyed by water (as suggested by the poster) then wouldn't a Grignard also be destroyed by ethanol?
As well as being excellent nucleophiles, Grignard reagents are also very strong bases because they essentially function as alkyl anions. T... |
If I have the pressure and temperature of a substance in its triple point, as well as its pressure and temperature in the critical point, how can I determine de boiling point of the substance at 1 atm of pressure?
Thanks. |
Alright, let’s take this one step at a time.
First of all, you want to determine a molecular formula, and among your known data you have a mole fraction. This suggests it’s a good idea to work with moles to solve the problem. As such, the first step is to convert the amount of water added and magnesium sulfate hydra... |
Interesting prompt!
There are plenty of reactions which could be performed underwater to release a large amount of energy. In fact, many substances react vigorously with water itself. You may have heard about how alkali metals such as sodium are not compatible with water, and there's [a good reason for it!](https://... |
In relation to the vaporization of THC, when smoked, is it possible that there is any active THC residue that becomes trapped inside the evaporator after the flame goes out?
Wouldn't some of the vapor get stuck inside because the instrument is not a hollow tube? |
Is an azide ion paramagnetic?
How do I use MO theory to show that it is or isn't?
I drew a sine wave diagram and filled up the 1pi and 2pi MOs, and since there is no unpaired electron, can I conclude that azide is NOT paramagnetic?
|
Is azide paramagnetic? |
Why is the rate of water exchange at Al(III) centres so slow ?
According to [this medical book][1] (p.5) it is $10^{5}$ times faster at Mg(II).
[1]: https://books.google.co.uk/books?id=VURZcorw_3gC |
> I remember using both 95% ethanol and absolute ethanol quite a few times. You'd need absolute ethanol for a reaction that would fail if water was present, such as a Grignard reaction. I can't remember whether the absolute ethanol was in an ordinary bottle or the type with a rubber septum (where you keep the liquid un... |
I'm trying to figure out what my optimal current density would be in respect to the limiting current density.
How do you calculate concentration polarization and limiting current density in an electrolytic cell. There are two copper electrodes and a 2M copper nitrate solution. The average current density was 0.375 ... |
I'm trying to figure out what my optimal current density would be in respect to the limiting current density.
How do you calculate concentration polarization and limiting current density in an electrolytic cell. There are two copper electrodes and a $2M$ copper nitrate solution. The average current density was $0.3... |
I'm trying to figure out what my optimal current density would be in respect to the limiting current density.
How do you calculate concentration polarization and limiting current density in an electrolytic cell. There are two copper electrodes and a $2\:\mathrm{M}$ copper nitrate solution. The average current densi... |
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