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First, try to be clear. Nobody can dissolve 0.1 M of anything in water. 0.1 M is not an amount. It is a concentration. I think you should replace "M" by "mole".
Second, you must mention the amount of water used to dissolve your product, or the final volume. I think you should rewrite your demand in such a way : "If... |
The question is in the title.
So could you please answer the question :
If I dissolve 0.1 mol of CaCl2.2H2O in Water, do i get a 0.1 M CaCl2 solution ? |
Not sure if this belongs on Chemistry or Physics stackexcahnge.
As water freezes into ice, it turns into a solid, and expands as it forms a crystal structure. But what happens to this crystal structure as it continues to cool? For example, if you take ice and cool it down to -50C, how does the crystal structure al... |
Not sure if this belongs on Chemistry or Physics stackexcahnge.
As water freezes into ice, it turns into a solid, and expands as it forms a crystal structure. But what happens to this crystal structure as it continues to cool? For example, if you take ice and cool it down to -50C, how does the crystal structure al... |
In a laboratory setting, the most common solvent removal method is rotary vacuum distillation. This is something I have performed many times, starting in organic chemistry labs. However, I am interested in learning of other solvent removal techniques.
Specifically, I am having a lot of trouble removing trace levels ... |
What are common solvent removal methods? |
The [Arrhenius equation][1] states that:
$$k=A\mathrm e^{\frac{-E_\mathrm a}{R T}}$$
[1]: https://en.wikipedia.org/wiki/Arrhenius_equation
What is the mathematical proof for this equation? |
>[![enter image description here][1]][1]
If you look at this compound, only the benzylic carbon on the top has a hydrogen attached to it, so how do we oxidize only the top part without touching the lower one (not sure if this product is right), and what happens to the $\ce{-CH2}$ in the middle?
Also, does benzy... |
Does an aryl compound with any functional group attached to it, undergo benzylic oxidation? |
[![enter image description here][1]][1]>[![enter image description here][2]][2]
If you look at this compound, only the benzylic carbon on the top has a hydrogen attached to it, so how do we oxidize only the top part without touching the lower one (not sure if this product is right), and what happens to the $\ce{-C... |
This is a quote from my textbook:
>The irregular trend in the first ionisation enthalpy of 3d lmetals,can be accounted for by considering that the removal of one electron alters the relative energies of 4s and 3d orbitals. So the unipositive ions have dn configuration with no 4s electrons.There is thus a reorganizatio... |
Zn which has the highest ionisation enthalpy in 3d series.The reason given in my textbook is:
>The value of zinc is higher because it represent ionisation from 4s level.
This is not correct because for every 3d element ionisation is from 4s orbital. The explanation I found for this is from this site is:
https:... |
Why Zn has highest ionisation enthalpy in 3d series? |
I have given the following equation: $A + 2B \rightarrow C$
$ v = –k\cdot [A]\cdot[B]^2$
gives me the orders 1 for A and 2 for B. That results in a total order of the reaction of 3.
So far so good. But I have given the following plot for linearization:
[![enter image description here][1]][1]
But this line... |
For the extraction of chromium, fusion of chromite ore with sodium or potassium carbonate in excess of air is done.
What exactly happens in this 'fusion' process? |
What does it mean to 'fuse' ores? |
If I dissolve $\pu{0.1 M}$ of $\ce{CaCl2.2H2O}$ in water, do I get a $\pu{0.1 M}$ $\ce{CaCl2}$ solution? |
If I dissolve 0.1M of CaCl2.2H2O in water, do I get a 0.1M CaCl2 solution? |
Rate determining step for parallel reaction? |
In classical analytical chemistry, absorbance values in Beer's law can theoretically range from 0 to infinity.
As general rule of thumb neither high, nor very low absorbance are used for constructing calibration curves. The reason for avoiding high absorbance is that when absorbance is 2, only 1% light reaches the ... |
How to calculate the parts-per-million concentration from a percent concentration? |
Suppose I have a reaction N2+3H2----->2NH3( Haber process).If we have to calculate the average rate of reaction of the above we follow the reasoning the rate of consumption of N2 is one- third that of H2 and half that of production of NH3.We go ahead and divide the change in concentration of N2 or H2 or NH3 by their st... |
Suppose I have a reaction (Say it is the Haber process):
$$\ce{N2 + 3H2 <=> 2NH3}$$
If we have to calculate the average rate of reaction of the above we follow the reasoning the rate of consumption of $\ce{N2}$ is one- third that of $\ce{H2}$ and half that of production of $\ce{NH3}$. We go ahead and divide the c... |
> My doubt is why rate of reaction is taken as the rate of consumption of N2?
It's done that way because rates have units, and most people don't pay enough attention to the units. Usually in chemistry, rates are units of _moles_ per unit time (per unit volume or per unit catalyst mass or per unit surface area or s... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background.
... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background.
... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background.
... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background. Here... |
I was working on a problem regarding the relative acidity of oxoacids in the form $\ce{HYO3}$ where $\ce{Y}$ represents a group 17 element.
The question (which is from a worksheet created by a chemistry instructor at my institution) is as follows:
>Which of the following is the most acidic: $\ce{HBrO3}$, $\ce{HFO3}$,... |
I was working on a problem regarding the relative acidity of oxoacids in the form $\ce{HYO3}$ where $\ce{Y}$ represents a group 17 element.
The question (which is from a worksheet created by a chemistry instructor at my institution) is as follows:
>Which of the following is the most acidic: $\ce{HBrO3}$, $\ce{HFO3}$,... |
Using an eluent of 1.00 mM NaHCO3 and 8.00 mM Na2CO3 in Milli-Q water, chromatographs were taken of the following anions: fluoride, chloride, nitrate, sulfate And phosphate. Why were the retention times of sulfate and phosphate longer than those of chloride, nitrate, and fluoride? The retention time of phosphate is no... |
In ion chromatography there are multiple retention mechanisms, the ion-exchange is the primary one. However, let us keep it simple.
You should be able to explain why monovalents retain less than divalents? Use Coulomb's law! The force of attraction between the ion and the ion-exchange on stationary phase is proporti... |
What will be the effects of intramolecular hydrogen bonding on the stability of a molecule? Will it increase or decrease the overall stability of a molecule? Or will it not have any impact on the stability?
Why do I think intramolecular hydrogen bonding increases the stability?
I've learn that formation of a bond... |
Zn which has the highest ionisation enthalpy in 3d series.The reason given in my textbook is:
>The value of zinc is higher because it represent ionisation from 4s level.
This is not correct because for every 3d element ionisation is from 4s orbital. The explanation I found for this is from this site is:
https:... |
Consider this graph of the titration of a weak acid and a strong base:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/qmGNP.png
The buffering region is strongest at the midpoint of titration because there is equal concentrations of acetic acid and its conjugate base.
>My question... |
Why does the concentration of the acid equals that of the base at the mid-point of titration? |
Consider this graph of the titration of a weak acid and a strong base:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/qmGNP.png
The buffering region is strongest at the midpoint of titration because there is equal concentrations of acetic acid and its conjugate base.
>My question... |
For example, this reaction, is a dehydration reaction
$\ce{ HNO3+ P4O10 -> N2O5 + HPO3} $
If I were only given the reactants side of the equation, how would I predict the products side of it? |
How to predict the products of an inorganic dehydration reaction? |
$P_4O_{10}$ is known to be a dehydrating agent. It removes $2H$ and $1O$ from any substance it may encounter. In order to withdraw $H_2O$ from nitric acid, it must find at least 2 $H$ atoms. One molecule$HNO_3$ is not enough. So you have to use at least two molecules of $HNO_3$. What remains from $2 HNO_3$ after removi... |
I am doing an experiment for a miticide for honey bees. I will be dissolving 600 g of 99.6 % oxalic acid in one liter vegetable glycerin at 150 °F. I have been told it will give off formic acid fumes while mixing and heating. I don't think it will until it get to the melting temperature of oxalic acid. Is there any saf... |
First Law of Thermodynamics is expressed as<sup>[1]</sup>
>The internal energy of an isolated system is constant.
If $w$ denotes the work done on a system, $q$ for the energy transferred as heat to the system, and $\Delta U$ for the resulting change in internal energy, then it follows that $$\Delta U = q + w \lab... |
What gasses are typically produced when biomass is incinerated at high temperatures (600 C) in high oxygen environments and what is a typical composition of the ashes left behind? |
So as I've been told, when a substance melts, the actual bonds of the substance aren't broken, only the IMFs (inter-molecular forces). So why is it that metal groups decrease in melting points going down when they should be increasing because more shells exist thus ions in the lattice will be larger so more IMFs th... |
I have an electric device which frequently gets very oily (it's a vaporizer for herbs). It came with a few individually packaged small "tissues" drenched in "isopropyl alcohol". I've used up them all now to clean the insides.
After each cleaning session, I wait a few minutes before I put in new herbs and heat it up ... |
How (in)flammable is "isopropyl alcohol" really? |
I have been told that with the help of crystal field theory, we can decide the electronic configuration (t2g eg configuration) of the metal ion in a complex.
For example, in octahedral complexes, if the ligand is a strong field ligand, pairing of electron in t2g will be favourable, rather than the electron occupying a... |
I have been told that with the help of crystal field theory, we can decide the electronic configuration (t2g eg configuration) of the metal ion in a complex.
For example, in octahedral complexes, if the ligand is a strong field ligand, pairing of electron in t2g will be favourable, rather than the electron occupying a... |
The following table is from Solomons, Fryhle and Snyder Organic Chemistry, chapter 3, An Introduction to Organic Reactions and Their Mechanisms: Acids and Bases:
>**Table 3.8** Isotopic substituents and inductive effect
>$$ \small
\begin{array}{ccc}
\hline
\text{Acid} & \ce{pK_a} & \text{Inductive effect of the ... |
Why is d3-acetic acid more acidic than acetic acid? |
**Empirical data**
If you analyze crystal structure data for short intermolecular distances between hydrogen atoms and potential acceptor atoms, you will find a distribution of these angles. The simplest explanation for this distribution is that there is a favorable interaction that is strongest for the most commonl... |
I was wondering if anyone could provide me with a method to solving as I do not know what I am doing wrong after multiple attempts? |
Whenever you are given concentrations vs. **time**, think "integrated rate law." There are three integrated rate laws that your instructor will either give you or expect you to know:
(1) for a zero order reaction: $[A]_t = -kt + [A]_0$
(2) for a 1st order reaction: $ln[A]_t = -kt + ln[A]_0$
(3) for a 2nd order... |
Whenever you are given concentrations vs. **time**, think "integrated rate law." There are three integrated rate laws that your instructor will either give you or expect you to know:
(1) for a zero order reaction: $[A]_t = -kt + [A]_0$
(2) for a 1st order reaction: $ln[A]_t = -kt + ln[A]_0$
(3) for a 2nd order... |
Does anyone know or could make an educated guess as to the conductivity/resistivity of molten lithium carbonate? Ideally, around 750 degrees C. |
Whenever you are given concentrations vs. **time**, think "integrated rate law." There are three integrated rate laws that your instructor will either give you or expect you to know:
(1) for a zero order reaction: $[A]_t = -kt + [A]_0$
(2) for a 1st order reaction: $ln[A]_t = -kt + ln[A]_0$
(3) for a 2nd order... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background. Here... |
Consider this graph of the titration of a weak acid and a strong base:
[![Graph of the titration of a weak acid and a strong base][1]][1]
The buffering region is strongest at the midpoint of titration because there is equal concentrations of acetic acid and its conjugate base.
>My question is why at the midpoi... |
I have been told that with the help of crystal field theory, we can decide the electronic configuration ($\mathrm{t_{{2g}}}$ $\mathrm{e_g}$ configuration) of the metal ion in a complex.
For example, in octahedral complexes, if the ligand is a strong field ligand, pairing of electron in $\mathrm{t_{{2g}}}$ will be favo... |
This problem seems to have wrong data ! Look !
The molar mass of $Ca_2SiO_4$ is $172$. The molar mass of $Ca_3SiO_5$ is $228$. If you mix $3$ moles $Ca_2SiO_4$, (= $516$ g), and $4$ moles $Ca_3SiO_5$, (= $912$ g), the total weight is : $516 + 912 = 1428$ g. This mixture contains $3+4 = 7$ moles of $SiO_2$, which weig... |
**The data in your Table is incorrect.**
- Maya Paabo, Roger G. Bates and R. A. Robinson ("[Dissociation of Acetic Acid-d3 in Aqueous Solution and Related Isotope Effects from 0 to 50°](https://doi.org/10.1021/j100874a037)", J. Phys. Chem. 1966, 70, 2, 540-543) report that the $\mathrm{p}K_\text{a}$ of the deuterio... |
The following table is from Solomons, Fryhle and Snyder Organic Chemistry, chapter 3, An Introduction to Organic Reactions and Their Mechanisms: Acids and Bases:
>**Table 3.8** Isotopic substituents and inductive effect
>$$ \small
\begin{array}{ccc}
\hline
\text{Acid} & \ce{pK_a} & \text{Inductive effect of the ... |
The data reported from Solomons, Fryhle and Snyder Organic Chemistry is **incorrect.**
- Maya Paabo, Roger G. Bates and R. A. Robinson ("[Dissociation of Acetic Acid-d3 in Aqueous Solution and Related Isotope Effects from 0 to 50°](https://doi.org/10.1021/j100874a037)", J. Phys. Chem. 1966, 70, 2, 540-543) report t... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background. Here... |
Would a set of chemical data with a relative standard deviation of 0.6% or 20% be more reproducible?
My reasoning is that because it's easier to make mistakes and have a wide range of data, the 20% would be more reproducible, even though it is not accurate.
A RSD of 0.6% would be extremely precise and therefore h... |
I know that Cp-Cv=R but I have also seen Cp-Cv=R/M being used in case of ideal gas.
So in what cases the former is used and in what cases is the latter used? |
For what processes is mayor's formula applicable? |
Question: Consider the following reaction at equilibrium at a total pressure that we will call P1.
2SO2(g)+O2(g) <-> 2SO3(g)
Suppose the volume of the system is compressed to 1/2 its initial volume and then equilibrium is reestablished. The new equilibrium total pressure will be:
a) Twice P1
b) Three times ... |
How do you find the ph of lime juice through titration? |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/plUBh.png
The key says the correct answer is B. I am wondering if this is because all exothermic reactions are spontaneous? |
Are all exothermic reactions spontaneous? |
No, it is not the case that all exothermic reactions are spontaneous. More generally, it doesn't even make sense to make a broad statement that a reaction is or is not spontaneous without also specifying the concentrations of reactants and products, since for a certain relative concentration of reactants and products,... |
No, it is not the case that all exothermic reactions are spontaneous. More generally, it doesn't even make sense to make a broad statement that a reaction is or is not spontaneous without also specifying the concentrations of reactants and products, since for a certain relative concentration of reactants and products,... |
Difference between vapor-phase transport and vapor-phase deposition? |
I'm reading Ostlund's Modern Quantum Chemistry. In Appendix B, the kinetic energy integral is evaluated using the Gaussian Basis functions as
T11=T11+T(A1(I),A1(J),0.0D0)*D1(I)*D1(J)
T12=T12+T(A1(1),A2(J),R2).D1(I).02(J)
T22=T22+T(A2(1),A2(J).0.ODO).D2(1).D2(J)
I understand T11 to be the kinetic energy in... |
I'm reading Ostlund's Modern Quantum Chemistry. In Appendix B, the kinetic energy integral is evaluated using the Gaussian Basis functions as
T11=T11+T(A1(I),A1(J),0.0D0)*D1(I)*D1(J)
T12=T12+T(A1(1),A2(J),R2).D1(I).02(J)
T22=T22+T(A2(1),A2(J).0.ODO).D2(1).D2(J)
I understand `T11` to be the kinetic... |
I buy and drink Nescafe Gold all the time. I also buy the smaller "caffeine-free" version of the same product, to use when it's too close to bedtime. It tastes very differently, which makes me assume that the caffeine does have a lot of taste.
However, maybe it's not simply due to the lack of caffeine? Maybe the pro... |
How can they "wash away" the caffeine from Nescafe Gold to produce that "de-caf" version? |
I know that Be has a tendency to create bonds with an increase covalent character so I can tell that BeF<sub>2</sub> is more covalent than let's say MgF<sub>2</sub>. So why is BeF<sub>2</sub> soluble in water while MgF<sub>2</sub> is barely soluble ? Shouldn't the ionic compound be more soluble ?
My guess is that the... |
How can you explain the solubility of Bef2? |
I'm reading Ostlund's Modern Quantum Chemistry. In Appendix B, the kinetic energy integral is evaluated using the Gaussian Basis functions as
T11=T11+T(A1(I),A1(J),0.0D0)*D1(I)*D1(J)
T12=T12+T(A1(1),A2(J),R2).D1(I).D2(J)
T22=T22+T(A2(1),A2(J).0.0D0).D2(1).D2(J)
I understand `T11` to be the kinetic... |
Although in 2020 there is a big movement of bankers marketers to lean the public towards Cashless society, Cash in the form of banknotes is still used in many if not most countries.
Cash banknotes can be very dirty in some occasions, especially in humid countries and storage areas.
Is the concept of a "self cle... |
Is the concept of a "self cleaning" banknote plausible? |
Question:
>Consider the following reaction at equilibrium at a total pressure that we will call $P_1$.
$$\ce{2SO2(g) + O2(g) <=> 2SO3(g)}$$
Suppose the volume of the system is compressed to $\frac 12$ its initial volume and then equilibrium is reestablished. The new equilibrium total pressure will be:
> a) T... |
Although in 2020 there is a big movement of bankers marketers to lean the public towards cashless society, cash in the form of banknotes is still used in many if not most countries.
Cash banknotes can be very dirty in some occasions, especially in humid countries and furthermore in humid storage areas.
Is the c... |
There are a lot of papers on optical rotation which cite Rosenfeld's (German) 1928 paper "Quantum mechanical theory of natural optical rotation..." [Quantenmechanische Theorie der naturlichen optischen
Aktivitat von Flussigkeiten und Gasen, Zeitschrift für Physik, Volume 52, Issue 3-4, pp. 161-174] as background. Here... |
Although in 2020 there is a big movement of bankers marketers to lean the public towards cashless society, cash in the form of banknotes is still used in many if not most countries.
Cash banknotes can be very dirty in some occasions, especially old banknotes in humid countries and furthermore in humid storage areas.... |
I read chapter 9 in the book Biochemistry. 5th edition Berg JM, Tymoczko JL, Stryer L.
New York: W H Freeman; 2002. (provided in the NCBI site here :https://www.ncbi.nlm.nih.gov/books/NBK22526/)
it describes the mechanism of action of the chymotrypsin enzyme. the catalysis is performed through the catalytic triad c... |
The paper of interest is [C.M. Wolfe][1] et al., "Growth and Dislocation Structure of Single-Crystal Ga(As$_{1-x}$P$_{x}$)", Journal of Applied Physics 36(12) 3790 (1965).
The key paragraph is:
> The GaAsP of this investigation has been prepared
by a closed-tube method utilizing a quartz ampoule
which is clea... |
I've learnt that when a molecule is non-superposable on its mirror image, it exists as a pair of enantiomers and is optically active. Absence of plane of symmetry is given to be one of the properties of chiral molecules.
Are there optically active molecules in which all atoms lie in the same plane?
I think, it is... |
Are there optically active molecules in which all atoms lie in the same plane? |
A 299 mL solution containing 21 g of a protein in toluene had an osmotic pressure of 0.053 atm at 27 degrees Celsius. What is the molar mass (in g/mol) of the protein? Only enter a numerical value rounded to the nearest whole number in the answer box below. Do NOT type in the unit (g/mol).
I keep using the osmotic p... |
Could Someone Help Me? |
> Consider the reaction $$\ce{2A + B -> Products},$$ when the concentration of $\ce{B}$ alone was doubled, the half-life did not change. When the concentration of $\ce{A}$ alone was doubled, the rate increased by two times. The units of the rate constant is:
> a) $\mathrm{s^{-1}}$
> b) $\mathrm{L\ mol^{-1}\ s^{-1... |
A 299 mL solution containing 21 g of a protein in toluene had an osmotic pressure of 0.053 atm at 27 degrees Celsius. What is the molar mass (in g/mol) of the protein? Only enter a numerical value rounded to the nearest whole number in the answer box below. Do NOT type in the unit (g/mol).
We can use the formula tha... |
> A 299 mL solution containing 21 g of a protein in toluene had an osmotic pressure of 0.053 atm at 27 degrees Celsius. What is the molar mass (in g/mol) of the protein?
We can use the formula that
$$\Pi = iMRT$$
with i being the van't Hoff factor, *M* being the molarity, R being the constant (0.08206), and T ... |
> A 299 mL solution containing 21 g of a protein in toluene had an osmotic pressure of 0.053 atm at 27 degrees Celsius. What is the molar mass (in g/mol) of the protein?
We can use the formula that
$$\Pi = iMRT$$
with i being the van't Hoff factor, *M* being the molarity, R being the constant (0.08206), and T ... |
> A 299 mL solution containing 21 g of a protein in toluene had an osmotic pressure of 0.053 atm at 27 degrees Celsius. What is the molar mass (in g/mol) of the protein?
We can use the formula that
$$\Pi = iMRT$$
where $\Pi$ is the osmotic pressure, $i$ the van't Hoff factor, $M$ being the molarity, $R$ being ... |
> A 299 mL solution containing 21 g of a protein in toluene had an osmotic pressure of 0.053 atm at 27 degrees Celsius. What is the molar mass (in g/mol) of the protein?
We can use the formula that
$$\Pi = iMRT$$
where $\Pi$ is the osmotic pressure, $i$ the van't Hoff factor, $M$ being the molarity, $R$ being ... |
In the Castner–Kellner process, why is sodium amalgam formed instead of hydrogen gas at the cathode?
If we electrolyse brine solution, then it will liberate hydrogen at cathode, not sodium, because $\ce{Na+}$ has a negative reduction potential while that of $\ce{H+}$ is (by definition) 0. What factor here causes the... |
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