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Can you say about the structure of CrO3 and the colour?
And also I have a question whether is it possible to have CrO3 when dichromate is heating with sulphuric acid? |
Can you say about the structure of $\ce{CrO3}$ and the colour?
And also I have a question whether is it possible to have $\ce{CrO3}$ when dichromate is heating with sulphuric acid? |
What is the structure and color of $\ce{CrO3}$?
Also, is it possible to have $\ce{CrO3}$ when dichromate is heating with sulphuric acid? |
What is the color and structure of CrO3? |
What is the structure and color of $\ce{CrO3}$?
Also, is it possible to produce $\ce{CrO3}$ when dichromate is heated with sulphuric acid? |
if I have a solution of KOH, for instance, which is in equilibrium with undissolved KOH at a temperature of 25 Celsius.
After raising the temperature to 50 celsius, the mass of dissolved KOH will decrease.
WHY? |
Why does raising the temperature affect the mass? |
Consider a solution of $\ce{KOH}$ which is in equilibrium with undissolved $\ce{KOH}$ at $25°\mathrm{C}$.
After raising the temperature to $50°\mathrm{C}$, the mass of undissolved $\ce{KOH}$ decreases. Why is this? |
Why does raising the temperature affect the mass of dissolved solute? |
What is the justification for Hückel's Rule? |
I know that this constant tells us the strength of the interaction between the metal and the ligand, so should it also mean that the *higher the constant, the stable the complex ?*
I need to make sure of it because in photometric titration, all that matters is the stability of complex, and if the constant is given, on... |
I receive $120~\mathrm{mL}$ bags of medicine in sterile water. The medicine is refrigerated and then packed with a significant amount of ice packs in an insulated bag. Generally three times the volume of all the medicine. When I remove the ice packs, they are still solid two hours after being packed. So, they are very ... |
Can Ice Packs Freeze Water at 21°C? |
I receive $120~\mathrm{mL}$ bags of medicine in sterile water. The medicine is refrigerated and then packed with a significant amount of ice packs in an insulated bag. Generally three times the volume of all the medicine. When I remove the ice packs, they are still solid two hours after being packed. So, they are very ... |
Can Ice Packs Freeze Water at 21 °C? |
just a thought that if we engineered metal ions to behave like non-metals in terms of chemical properties (by supplying or removing electrons), would the altered metal ions bond covalently?
would the ions be too unstable and begin to decay? |
is it possible to get two metals bonding covalently? |
How do I create a spreadsheet containing the coordinates and predicted bond angles, molecular properties, torsion properties, etc of a molecule? |
Can metal ions be engineered to behave like non-metals in terms of chemical properties (by supplying or removing electrons), would the altered metal ions bond covalently?
Would the ions be too unstable and begin to decay? |
Can two metals bonding covalently? |
Can two metals bond covalently? |
What is the mechanism for the photolysis of HX to dihydrogen and dihalogen ? From the low quantum yield (0.3% for HI according to one paper) it seems unlikely to be a chain process but I am not sure why it would not be. |
What is the mechanism for the photolysis of $\ce{HX}$ to dihydrogen and dihalogen ? From the low quantum yield (0.3% for $\ce{HI}$ according to one paper) it seems unlikely to be a chain process but I am not sure why it would not be. |
Consider a solution of $\ce{KOH}$ which is in equilibrium with undissolved $\ce{KOH}$ at $25\ \mathrm{^\circ C}$.
After raising the temperature to $50\ \mathrm{^\circ C}$, the mass of undissolved $\ce{KOH}$ decreases. Why is this? |
We have a investigation in my chemistry class in which we must calculate the amount of calcium carbonate in sea shells. We can have as many sea shells as we wish, as well as all lab equipment + hydrochloric acid of varying concentration from 0.5 mol/L to 2 mol/L. How is it to be done?
Thanks in advance. |
We have a investigation in my chemistry class in which we must calculate the amount of calcium carbonate in sea shells. We can have as many sea shells as we wish, lab equipment, and hydrochloric acid of varying concentration from $0.5~\mathrm{mol~dm^{-3}}$ to $2~\mathrm{mol~dm^{-3}}$. How is it to be done? |
Wouldn't it be great to be able to predict the melting point of a metal based on the atomic number and not by looking in some table for the value that was measured experimentally by someone else? Or to predict the same melting point for a simple salt like NaCl or KI by applying some formula to the atomic numbers of the... |
I know that $C-D$ and $C-T$ bonds are stronger than $C-H$ bonds, but is this generally true for isotopes of all elements? (By isotopes I mean stable ones with large half lives.) |
Do heavier isotopes of an element always form stronger bonds than the lighter ones? |
I know that $\ce{C-D}$ and $\ce{C-T}$ bonds are stronger than $\ce{C-H}$ bonds, but is this generally true for isotopes of all elements? (By isotopes I mean stable ones with large half lives.) |
What is the meaning of cmmol in chemistry? |
I came across a unit called $\text{cmmol dm}^{-3}$ in buffer solutions. What does this unit mean? |
For a given element do heavier isotopes form stronger bonds than lighter isotopes? |
Isovalent isotopes will have the same force constant. However the different masses of the isotope will affect the position of the vibrational state in its potential well. You can rationalise the difference in well depth briefly using the vibrational frequencies of a classical oscillator as the harmonic approximation to... |
In the contact process, the commercial process of producing $\ce{H2SO4}$, several reactions occur before the final product is produced:
> $\ce{S8_{(s)} +8O2_{(g)} -> 8SO2_{(g)}}~~~~~~~~~~\Delta H_{\mathrm{f}}=-70.9~\mathrm{kcal~mol^{-1}}$
> $\ce{2SO2_{(g)} +O2_{(g)} \xrightarrow{V2O5} 2SO3_{(g)}}~~~~~\Delta H_{\m... |
From [this source](http://www.2classnotes.com/digital_notes.asp?p=Extraction_of_Aluminium)
>Baeyer's process: This method is mainly applied when ferric oxide is present as chief impurity.
>Serpeck's process: This process is used when silica is present in considerable amount of bauxide ore.
I couldn't find any ... |
I have identified carvacrol and thymol via thin-layer-chromatography and via gas chromatography
On a normal silica plate the thymol has a higher Rf-value then carvacrol. The explanation for this would be the position of the hydroxyl-group and the difference size of the nearby methyl or isopropyl group. I think thymol ... |
It was the question I found in textbook,
Assuming that Air is oxygen I solved it this way
FeSO4 + O2 --> Fe2O3 + SO2
But in my textbook it's given that Ferrous (III) Sulphate is formed
Fe2(SO4)3
How is that? Am I wrong?
I find formation of FeIIIsulphate highly doubtful |
It was the question I found in textbook.
Assuming that air is oxygen I solved it this way:
$\ce{FeSO4 + O2 -> Fe2O3 + SO2}$
But in my textbook it's given that Ferric Sulphate is formed
$\ce{Fe2(SO4)3}$.
How is that? Am I wrong?
I find formation of Ferric Sulphate highly doubtful. |
It was the question I found in textbook.
Assuming that air is oxygen I solved it this way:
FeSO4 + O2 -> Fe2O3 + SO2}$
But in my textbook it's given that Ferric Sulphate is formed
$\ce{Fe2(SO4)3}$.
Or does $\ce{Fe2O3 + SO2}$ form $\ce{Fe2(SO4)3}$. $
How is that? Am I wrong?
I find formation of Ferric Su... |
It was the question I found in textbook.
Assuming that air is oxygen I solved it this way:
$\ce{FeSO4 + O2 -> Fe2O3 + SO2}$
But in my textbook it's given that Ferric Sulphate is formed
$\ce{Fe2(SO4)3}$.
Or does $\ce{Fe2O3 + SO2}$ form $\ce{Fe2(SO4)3}$.
How is that? Am I wrong?
I find formation of Ferric ... |
Could anyone tell me how I would go about calculating the pH of 100.0 mL of 0.100 M $\ce{H2NNH2}$ ($K_\text{b} = 3.0 \times 10^{-6}$).
Furthermore, how would this pH change when 20.0 mL of 0.200 M $\ce{HNO3}$ is added to the solution?
I’m not looking for only an answer, but rather the general method to solve the... |
I am asked to identify the highest and lowest energy conformations for the following bond-line structure (I think it is 2,2-dimethylbutane). I drew a Newman projection (for all 6 conformations) and was able to identify the lowest energy conformation correctly but the textbook solution for the highest energy conformatio... |
I am asked to identify the highest and lowest energy conformations for the following bond-line structure (I think it is 2,2-dimethylbutane). I drew a Newman projection (for all 6 conformations) and was able to identify the lowest energy conformation correctly but the textbook solution for the highest energy conformatio... |
Load your CIF file in [PLATON](http://www.cryst.chem.uu.nl/spek/platon/pl000000.html) and run `CALC-GEO`
In the `*.LIS` file generated, you'll find all the tables that you need, namely
* Bond Lengths (Angstrom)
* Bond/Valence Angles (Degrees)
* Torsion/Dihedral Angles (Deg.)
You can still use the `reg... |
Isovalent isotopes will have the same force constant. However the different masses of the isotope will affect the position of the vibrational state in its potential well. You can rationalise the difference in well depth briefly using the vibrational frequencies of a classical oscillator as the harmonic approximation to... |
I am asked to identify the highest and lowest energy conformations for the following bond-line structure (I think it is 2,2-dimethylbutane). I drew a Newman projection (for all 6 conformations) and was able to identify the lowest energy conformation correctly but the textbook solution for the highest energy conformatio... |
Isovalent isotopes will have the same force constant. However the different masses of the isotope will affect the position of the vibrational state in its potential well. You can rationalise the difference in well depth briefly using the vibrational frequencies of a classical oscillator as the harmonic approximation to... |
I am asked to identify the highest and lowest energy conformations for the following bond-line structure (I think it is 2,2-dimethylbutane). I drew a Newman projection (for all 6 conformations) and was able to identify the lowest energy conformation correctly but the textbook solution for the highest energy conformatio... |
I'm wondering why maleic anhydride interacts with the middle cycle of anthracene.
![enter image description here][1]
My thought concering product based stability:
I would have expected that a Diels Alder to the outer ring would be better giving more resonance stabilization because I expected a naphtalene part ... |
Very short answer:
$\Delta G = \Delta H - T\Delta S$
As this is an org-chem question, no need to solve the equation numerically. As you might know, $\ce{N2_{(g)}}$'s standard formation enthalpy ($\Delta H_\text{f}^\circ$) is 0 – at standard $T$ and $p$, $\ce{N2_{(g)}}$ is gaseous. Therefore, its enthalpic contrib... |
Stumbled across this interesting practice problem in my organic textbook. I have a few reasons for why $\ce{H4N+}$ is less acidic than $\ce{H3O+}$.
1) Let’s assess conjugate stability first. Conjugates are $\ce{H3N}$ and $\ce{H2O}$. Let’s look at central atom oxidation state. Nitrogen in ammonia has an oxidation sta... |
I'm wondering why maleic anhydride interacts with the middle cycle of anthracene.
![enter image description here][1]
My thought concering product based stability:
I would have expected that a Diels Alder to the outer ring would be better giving more resonance stabilization because I expected a naphtalene part ... |
Here are a number of resources that may be of use for your research.
The UCLA website presents tables and data in their webpage [Theory of Ultraviolet-Visible (UV-Vis) Spectroscopy][1], including reference tables of common functional groups, aromatics and compounds often used in the laboratory. (Many compounds you ... |
I have been writing a custom MD code for some time. I have been using the andersen thermostat, mainly because its ease of use, and the fact that I am not concerned with gathering dynamical data, but rather free energies. I have implemented the shake algorithm found in lammps. However, the thermostat seems to be underco... |
I am trying to simulate the excitation state of Acetone. I ran TDDFT for it both in gas phase and solvated state in water ( both implicit and explicit water).
The experimental data say that Acetone undergoes n->π* transition which means higher wavelength in gas phase ( λmax= ~276 nm ) and shorter wavelength in solva... |
Why Acetone does not behave like its computational values? |
Isovalent isotopes will have the same force constant. However the different masses of the isotope will affect the position of the vibrational state in its potential well. You can rationalise the difference in well depth briefly using the vibrational frequencies of a classical oscillator as the harmonic approximation to... |
I am trying to simulate the excitation state of Acetone. I ran TDDFT for it both in gas phase and solvated state in water ( both implicit and explicit water).
The experimental data say that Acetone undergoes n->π* transition which means higher wavelength in gas phase ( λmax= ~276 nm ) and shorter wavelength in solva... |
I am trying to simulate the excitation state of Acetone. I ran TDDFT for it both in gas phase and solvated state in water ( both implicit and explicit water).
The experimental data say that Acetone undergoes n->π* transition which means higher wavelength in gas phase ( λmax= ~276 nm ) and shorter wavelength in solva... |
I am trying to simulate the excitation state of acetone. I ran TDDFT for it both in gas phase and solvated state in water (both implicit and explicit water).
The experimental data say that acetone undergoes n->π* transition, which means it has a higher wavelength in gas phase ($\mathrm{\lambda_{max}}=$~$276~\mathrm{... |
If a lattice contains a solvent, lets say $\ce{NaCl}$ and water of crystallisation, what is the condition for a solvent molecule to change it's location?
From my current point of view I assume that such a water molecule is bound to a lattice ion by ion-dipole forces. It vibrates at that location until, randomly, t... |
I've done my research on this so I've seen the questions asking about the same premise without using plants.
Basically, this is a thought experiment I came up with. Whether or not I perform it depends on the feasibility. This is the reaction I'm thinking of:
$$
\ce{CO_2 \rightarrow C + O_2}
$$
From [NIST](ht... |
There are two stable isotopes of iridium, $\ce{^191Ir}$ and $\ce{^193Ir}$. If you randomly pick an iridium atom from a large collection of iridium atoms, which isotope are you more likely to select? |
Firstly, I would like to address the compound below.
![enter image description here][1]
This compound on elaborate elongation would result in this structure.
![enter image description here][2]
But is the below given numbering correct? I am just dubious that what if the same compound is given numbering... |
It was the question I found in textbook.
Assuming that air is oxygen I solved it this way:
$\ce{FeSO4 + O2 -> Fe2O3 + SO2}$
But in my textbook it's given that iron (III) sulphate is formed
$\ce{Fe2(SO4)3}$.
Or does $\ce{Fe2O3 + SO2}$ form $\ce{Fe2(SO4)3}$.
How is that? Am I wrong?
I find formation of iro... |
How to define the atom numbers in unsaturated hydrocarbons correctly according to IUPAC? |
> What is formed when you leave iron (II) sulfate in plain air?
It was the question I found in textbook.
Assuming that air is oxygen I solved it this way:
$$\ce{FeSO4 + O2 -> Fe2O3 + SO2}$$
But in my textbook it's given that iron (III) sulphate is formed
$\ce{Fe2(SO4)3}$.
Or does $\ce{Fe2O3 + SO2}$ for... |
What is formed when you leave iron (II) sulfate in plain air? |
I have a base $\ce{M(OH)_{3}}$ having 3 $\mathrm{p}K_{\mathrm{b}}$ values as,
$$
\mathrm{p}K_{\mathrm{b}_{1}} = 0.5\\
\mathrm{p}K_{\mathrm{b}_{2}} = 3.7\\
\mathrm{p}K_{\mathrm{b}_{3}} = 7.7\\
$$
If a strong acid is given as the titrant and phenolphthalein and methyl orange are given as possible indicators, how ... |
Is it possible for an element to have a calculated relative atomic mass that is higher than the relative isotopic mass of its most massive component isotope?
The equation is:
$\mathrm{Relative~Atomic~Mass}=\sum[{\mathrm{(Isotopic~Mass) \cdot (Relative~Abundance)]}} \times100\%$ |
Can we add concentrated $\ce{H2SO4}$ and concentrated $\ce{HNO3}$ to anisole?
I heard that we can't add acids into phenol and aniline which make them blast. |
I should probably add that I was originally given an unknown solid mixture of 2 salts. I separated the insoluble salt out by centrifuging and then decanting. I found that the insoluble salt is $\ce{MgCO3}$ (by adding $\ce{HCl}$ (bubbles) and $\ce{NaOH}$ into the solutoin (pcp jelly like white)). The decanted liquid was... |
I am trying to understand how to interpret the TDDFT results ( I know there is [another post][1] for this but it does not answer my question ). Here is part of the result from GAMESS:
![GAMESS TDDFT][2]
I downloaded [Chemissian][3] and this is its result for this state:
![Chemissian Output][4]
I hav... |
Load your CIF file in [PLATON](http://www.cryst.chem.uu.nl/spek/platon/pl000000.html) and run `CALC-GEO`
In the `*.LIS` file generated, you'll find all the tables that you need, namely
* Bond Lengths (Angstrom)
* Bond/Valence Angles (Degrees)
* Torsion/Dihedral Angles (Deg.)
You can still use the `reg... |
For the first time I'm doing [TD-DFT][1] calculations (wB97XD functional) in Gaussian 09 for an *open-shell* system and the results look like the hell of a mess for me. The molecule is rather big, so I started with just 10 excited states to see how it would work.
First off, the ground electronic state is $^2A_2$, or... |
Arranging spheres ABABAB type in 2D gives us close packing.
Now, this layer if arranged in ABABAB (in 3D) gives us HCP and if arranged in ABCABC (in 3D) gives us FCC.
What do we get if we arrange it in AAAAA type (in 3D) ?
Please help. I have been struggling with this question for a long time.
(we are talkin... |
Which unit cell do we obtain if spheres are arranged in ABABAB type in 2D and then that 2D layer is arranged in AAAAAA type in 3D? |
if I have a container in vacuum filled with I2 gas and then I bombard it with high speed electrons say using electron gun, would i be able to get I+ & I- ions or would I only get I2+ plus an ejected electron?
thanks |
is it possible to break the bonds of diatomic elements such as fluorine or iodine and create positive and negative ions by electron bombardment? |
if I have a container in vacuum filled with I<sub>2</sub> gas and then I bombard it with high speed electrons say using electron gun, would i be able to get I+ & I- ions or would I only get I2+ plus an ejected electron?
|
if I have a container in vacuum filled with $\ce{I2}$ gas and then I bombard it with high speed electrons say using electron gun, would i be able to get $\ce{I+}$ & $\ce{I-}$ ions or would I only get $\ce{I^2+}$ plus an ejected electron?
|
The unit $cmmol\,dm^{-3}$ is the same as $mmol_{c}\,dm^{-3}$ which denotes the millimoles of charge per litre. I think the former notation is not well used anymore. On the other hand, latter is used often and a google search would return a number of references. For example,
http://micromaintain.ucanr.edu/Prediction/... |
If one were to dissolve magnesium citrate (about 100 mg) in water (about 70 ml) and let the solution sit for 48 hours, would the solution be exactly the same as one dissolved and consumed right away?
How does one explain the difference in taste from a 48-hour solution and a 5-minute solution? |
this is your output, right?
TRANSITION DIPOLE, A.U. OSCILLATOR
HARTREE EV X Y Z STRENGTH
0 A -193.0290234748 0.000
1 A -192.8724089055 4.262 0.0001 0.0000 0.0001 0.000
2 A -192.783133562... |
There was a question in one of my exam papers to draw the resonance structures for $\ce{N2O}$. But the resonance structures I drew were not given marks.
The top 2 structures are the ones I drew and the bottom 3 are the ones in the marking scheme.
I have the doubt, whether my structures are unstable, like $\ce{N}$ a... |
What are the correct resonance structures of nitrous oxide? |
While studying the Crystal Field Theory I was told Dq is a unit, related to the unit Δo by the relation Δo = 10 Dq. But aren't Δo and Dq variables, not units? The unit is of energy, such as eV or Joules, these are symbols to represent a particular value of energy, which could be anything. So what do we mean when we say... |
What does it mean, Δo= 10 Dq? |
In Crystal Field Theory what does Δo= 10 Dq mean? |
While studying the Crystal Field Theory I was told $D_q$ is a unit, related to the unit $\Delta_{\mathrm{O}}$ by the relation $\Delta_{\mathrm{O}} = 10 D_q$. But aren't $\Delta_{\mathrm{O}}$ and $D_q$ variables, not units? The unit is of energy, such as eV or joules, these are symbols to represent a particular value of... |
In Crystal Field Theory what does Δo=10Dq mean? |
Can anyone tell me how I can convert a rate constant derived from first order kinetics (units are $\mathrm{h^{-1}}$) into an actual rate (turnovers/h)?
The scenario is that I know my rate constant for a molecule degrading in solution and it is $0.012\ \mathrm{h^{-1}}$. I know that I have $10^{14}$ catalyst molecules... |
I am asked to identify the number of stereoisomers that are possible for $\ce{H_2C=CHCH_2CH_2CH_2CH=CH_2}$
I drew the bond-line structure as follows, and I think that there can be cis and trans isomers, but my answer is wrong. The correct answer states that since neither of the double bonds exhibit stereoisomerism, ... |
I am asked to identify the number of stereoisomers that are possible for $\ce{H_2C=CHCH_2CH_2CH_2CH=CH_2}$
I drew the bond-line structure as follows, and I think that there can be *cis* and *trans* isomers, but my answer is wrong. The correct answer states that since neither of the double bonds exhibit stereoisomeri... |
I am asked to identify the number of stereoisomers that are possible for $\ce{H_2C=CHCH_2CH_2CH_2CH=CH_2}$
I drew the bond-line structure as follows, and I think that there can be *cis* and *trans* isomers, but my answer is wrong. The correct answer states that since neither of the double bonds exhibit stereoisomeri... |
A friend of mine was looking over the definition of pH, and wondering if it is possible to have a negative pH level. From the equation below, it certainly seems possible—just have a $1.1$ (or something $\gt 1$) molar solution of $\ce{H+}$ ions:
$$\text{pH} = -\log([\ce{H+}])$$
(Where $[\ce{X}]$ denotes the concentrat... |
I am asked to identify the number of stereoisomers that are possible for $\ce{H_2C=CHCH_2CH_2CH_2CH=CH_2}$
I drew the bond-line structure as follows, and I think that there can be *cis* and *trans* isomers, but my answer is wrong. The correct answer states that since neither of the double bonds exhibit stereoisomeri... |
During the formation of $\ce{Al2O3}$ from 5.4 grams of $\ce{Al}$ and enough oxygen, the temperature of 2 kg of water climbs by 20 degrees. What’s the enthalpy of formation of $\ce{Al2O3}$ (per mole) ?
What I tried:
The balanced reaction:
$$\ce{4Al + 3 O2 -> 2 Al2O3}$$
5.4 grams of $\ce{Al}$ are 0.2 moles.
... |
I'm extracting DMT from Acacia Confusa via ACID/Base. I extracted the DMT with H20 and Acetic Acid, converting it to DMT-Acetate. Here, I used a non polar Solvent, Naptha, to defat the material, causing an emulsion. I used NACL to break the emulsion... this caused a thick layer of black tar to form on top of the aqueo... |
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