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We know that the structure of CH4 is tetrahedral, and not planar tetragonal, as a tetrahedron enables maximum distribution of H-atoms in space, as they repulse from each other. This is proved by the fact **that each H-C-H bond angle is equal in magnitude.**
So in case of PCl5, why should the shape be trigonal bipyram... |
Is PCl5 really trigonal bipyramidal in shape? |
We know that the structure of CH4 is tetrahedral, and not planar tetragonal, as a tetrahedron enables maximum distribution of H-atoms in space, as they repulse from each other. This is proved by the fact **that each H-C-H bond angle is equal in magnitude.**
So in case of PCl5, why should the shape be trigonal bipyram... |
I'm no chemist, so bear with me.
From my understanding, the reason metal oxidation occurs is because the metal is losing electrons to the oxygen ions in the air; and that an ion is an atom or molecule which either has more or less electrons than the "standard" of that atom/molecule; which is why it's "taking" electr... |
What determines the atom or molecule that receives electrons during oxidation? |
What is the scientific term for the separation of dust particles from air by suction through a specialized flask in a way similar to the operation of a bong?
The thing that led me to this was a vacuum cleaner that uses water to separate dust and other particles from the air by vacuuming the air through a water bowl... |
We know that the structure of $\ce{CH4}$ is tetrahedral, and not planar tetragonal, as a tetrahedron enables maximum distribution of $\ce{H}$-atoms in space, as they repulse from each other. This is proved by the fact that each $\ce{H-C-H}$ bond angle is equal in magnitude.
In the case of $\ce{PCl5}$, why should the... |
We know that the structure of $\ce{CH4}$ is tetrahedral, and not planar tetragonal, as a tetrahedron enables maximum distribution of $\ce{H}$-atoms in space, as they repulse from each other. This is proved by the fact that each $\ce{H-C-H}$ bond angle is equal in magnitude.
In the case of $\ce{PCl5}$, why should the... |
I would like to ask a question about the ordering of the $\ce{X}$ spins on the right hand side of an $\ce{AX2}$ energy diagram.
I was given the diagram here below:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/fZkyG.png
and asked to evaluate why this diagram results in a triplet. ... |
(1) $\ce{PH3(g) <=>[W]PH3(adsorption)->[W]P(s) + 3/2 H2(g)}$
The **decomposition** of phosphine on tungsten surface at low pressure is a pseudo first order reaction. This is because the rate of reaction depends on the partial pressure of phosphine and which depends on the surface area of tungsten covered by phosphin... |
My teacher said that on the periodic table there is a "nose" formed by Al, Zn, Ag, and Cd. She said that they are all fixed charged (+3, +2, +1, and +2 respectively), and said that if I write them in ionic equations, I just say Silver Nitrate instead of Silver (I) Nitrate. She also said to put all Al as +3 charge in al... |
My teacher said that on the periodic table there is a "nose" formed by Al, Zn, Ag, and Cd. She said that they are all fixed charged (+3, +2, +1, and +2 respectively), and said that if I write them in ionic equations, I just say Silver Nitrate instead of Silver (I) Nitrate. She also said to put all Al as +3 charge in al... |
I have an aluminium surface covered with some plastic, which I intend to dissolve in order to clean the surface. On the note for the plastic I have applied, it says that it contains the following:
- VM&P (what is this??)
- Naphtha
- Hexane
- Toluene
- Methyl Ethyl Ketone
- Resins
What solvent would yo... |
I have an aluminium surface covered with some plastic, which I intend to dissolve in order to clean the surface. On the note for the plastic I have applied, it says that it contains the following:
- 2-butanone
- Naphtha
- Hexane
- Toluene
- Methyl Ethyl Ketone
- Resins
What solvent would you recommend... |
I have an aluminium surface covered with some plastic, which I intend to dissolve in order to clean the surface. On the note for the plastic I have applied, it says that it contains the following:
- 2-butanone
- Naphtha
- Hexane
- Toluene
- Resins
What solvent would you recommend to dissolve this plastic... |
In light of [this question](https://chemistry.stackexchange.com/q/73614/7450) and its answers, I hope to get some insights into the pH of LaCl3 in water and its pH relationship to La(OH)3 percipient's pKa?
What can be done in order to prevent LaCl3 from forming La(OH)3 and maintaining the pH 24'C - 25'C?
When cr... |
I have an aluminium surface covered with some plastic, which I intend to dissolve in order to clean the surface. On the note for the plastic I have applied, it says that it contains the following:
- 2-butanone Naphtha
- Hexane
- Toluene
- Resins
What solvent would you recommend to dissolve this plastic, wi... |
Dhruba Charan Dash published the problem in his analytical chemistry textbook (ISBN 9788120353008). This is the picture that goes with the question:
[![enter image description here][1]][1]
Notice that the scale of the chemical shift increases with the strength of the magnetic field $B$. This means they are using ... |
Can the Arrhenius equation be used if the reactants are in the solid state and if I can use it for any state, how do I do so?
|
I have done an experiment where I dissolved four diffrent substituted phenols in acid, basic, and buffer solutions, and recorded the UV-Vis spectra for each. I'm supposed to pick a wavelength where the absorbances for the protonated, normal and dissociated forms are very different. I then use these equations given to m... |
How many times should I run a solvent extration experiment through? |
I have done an experiment where I dissolved four different substituted phenols in acidic, basic, and buffer solutions, and recorded the UV-Vis spectra for each. I'm supposed to pick a wavelength where the absorbances for the protonated, normal and dissociated forms are very different. I then use these equations given t... |
Clear distinction has to be made between Arrhenius-equation and transition state theory. The formulas for TST can be derived, as opposed to Arrhenius equation, which by itself, is not based on a solid physical derivation. Basically any process can be modeled by an Arrhenius equation that has the formula:
$$ r \propt... |
I have done an experiment where I dissolved four different substituted phenols in acidic, basic, and buffer solutions, and recorded the UV-Vis spectra for each. I'm supposed to pick a wavelength where the absorbances for the protonated, normal and dissociated forms are very different. I then use these equations given t... |
Why is the blue flame the hottest on a Bunsen burner?
I thought the outermost part of the flame must be the hottest region because of complete combustion of gases taking place there. Where am I getting wrong?
 |
Why is the outermost part of the Bunsen burner flame not the hottest region? |
So I have a question concerning a reaction mechanism for the reaction below.
[![enter image description here][1]][1]
I know for certain that I get the alfa anomer, but I can't explain it. When I draw out the mechanism it doesn't make sense to me.
[![enter image description here][2]][2]
I think what throws... |
Can a per-acetylated sugar anomerize? |
Can there be a compound which stops the pesticide from entering into the fruit or vegetable? For example, a solution which is sprayed before pesticides and somehow blocks pesticides from entering into the fruit? |
Can there be a compound which stops the pesticide from entering into the fruit or vegetable? |
While studying group theory, I've got confused by the following statement:
> For a molecule to have a permanent dipole moment, it must have an asymmetric charge distribution. The point group of the molecule not only determines whether the molecule may have a dipole moment but also in which direction(s) it may point.... |
The word "stability" itself isn't very clear, so you have to figure out exactly what it is stable with respect to. If you look up the data, the reaction
$$\ce{NaO2 (s) -> Na(s) + O2(g)}$$
is not enthalpically favourable. So, $\ce{NaO2}$ is actually stable with respect to decomposition to the constituent elements.... |
While I can't find specific justification for the surface, the first competition involved both gold and silver "racetracks."
- [Drivers gear up for world’s first nanocar race](https://doi.org/10.1038/544278a)
- [How to build and race a fast nanocar](https://doi.org/10.1038/nnano.2017.137)
The competition involve... |
I have a conceptual physical chemistry question here.
> A thermos bottle containing milk is shaken vigorously. Consider the milk as the system. Will the temperature rise as a result of the shaking?
My answer to this is **yes**, but I'm having trouble finding an equation that explains this result.
The best I h... |
I am unable to get two things straight
1. Shouldn't higher temperatures mean higher energy for the molecules and therefore a greater rate of effusion?
2. Even if this is so, isn't absolute temperature th... |
Why is the rate of effusion of a gas inversely proportional to (absolute) temperature? |
> (iv) Rate of effusion of a gas: The rate of passing of a gas through an orifice may be given as:
>$$r=\frac{PA}{\sqrt{2\pi RTm}}$$
<!
I am unable to get two things straight:
1. Shouldn't higher... |
Why does potassium permanganate oxidize formic acid and oxalic acid, but has no reaction with benzoic acid and acetic acid? |
> (iv) Rate of effusion of a gas: The rate of passing of a gas through an orifice may be given as:
>$$r=\frac{PA}{\sqrt{2\pi RTm}}$$
<!
I am unable to get two things straight:
1. Shouldn't higher... |
I would like to ask a question about the ordering of the $\ce{X}$ spins on the right hand side of an $\ce{AX2}$ energy diagram.
I was given the diagram here below:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/fZkyG.png
and asked to evaluate why this diagram results in a triplet. ... |
> **(iv) Rate of effusion of a gas:** The rate of passing of a gas through an orifice may be given as:
> $$r = \frac{PA}{\sqrt{2\pi RTm}}$$
> where
> $P = $ Partial pressure of the gas
> $A = $ Area of cross-section of the orifice
> $R = $ Gas constant
> $T = $ Absolute temperature
> $m = $ Molar ... |
## No, it would not ##
A dipole means that there is a difference (in charge) from one "side" to another "side"
If we have determined that something is symmetric, it means the "sides" are equal to each other - and that as you rotate $(\frac{1}{n})$ around the symmetry axis, **everything stays the same.** If there ... |
## No, it would not ##
A dipole means that there is a difference (in charge) from one "side" to another "side".
If we have determined that something is symmetric, it means the "sides" are equal to each other — and that as you rotate $\left(\frac{1}{n}\right)$ around the symmetry axis, **everything stays the same.... |
While studying group theory, I've got confused by the following statement:
> For a molecule to have a permanent dipole moment, it must have an asymmetric charge distribution. The point group of the molecule not only determines whether the molecule may have a dipole moment but also in which direction(s) it may point.... |
Why does dipole must lie parallel to a rotation symmetry axis? |
I have a range of sodium hydroxide solutions with different concentrations. (from 1.0 mol dm^-3 to 0.5 mol dm^-3). The max volume of each is 100ml. How can you easily dispose of these? Can I pour them down the sink? |
How to dispose of NaOH solution? |
How can I find the Van der Waals constants (a and b) without any critical values? |
What should be orupad name of given compound (see image)? |
What should be IUPAC name of given compound (see image)? |
I think the name should be **1-carbamoylpentane-3-sulphonic acid**, but the answer sheet mentions it as **2-carbamoylpentane-3-sulphonic acid**:
[![2-carbamoylpentane-3-sulphonic acid][1]][1]
Can anyone please explain why the chain starting with methyl group is considered parent chain instead of one starting with... |
Why does potassium permanganate oxidize formic acid and oxalic acid, but has no reaction with benzoic acid and acetic acid?
EDIT (Apologies for the unclear question):
The reactions were heated in a water bath (~70-80 deg. C). Oxalic acid had turned colorless: C2H2O4 + KMnO4 + 6H+ ------> CO2 + H2O + (Mn2+) + KOH
... |
I'd like to do a class experiment as a metaphor for human relationships. Two people each have a different chemical which evaporates quickly (at STP). There is one glass between them. If only one person pours his/her chemical into the glass, it quickly evaporates. However, if both pour equal portions of their respec... |
If one were to take 1 mole of pure liquid Calcium Chloride (at 600 C) and bombard it with 7.65 * 10^14 Cu of x-rays (75 keV), how the calcium chloride become chemically altered in anyway? Would the radiation cause the calcium and/or chloride ions to further ionize into a form that would not bond with the other ions?
... |
What is the formula for vapor pressure of liquid related to surface tension of liquid? Can anyone please tell me? i know that if surface tension is more, vapor pressure will be less. Toluene evaporates faster than ethanol even though it is having more surface tension. How can i relate between every solvent through for... |
What is the formula for vapor pressure of liquid related to surface tension of liquid? Can anyone please tell me? |
How do we know the taste of compounds, and their smell too, when some of them are poisonous. My textbook had that Lead is sweet in taste, but it's poisonous. So, how exactly do we determine their taste and odour of such compunds? |
How is taste of chemical compounds determined? |
Why does potassium permanganate oxidize formic acid and oxalic acid, but has no reaction with benzoic acid and acetic acid?
The reactions were heated in a water bath (~70-80 °C). Oxalic acid had turned colorless:
$$\ce{C2H2O4 + KMnO4 + 6 H+ -> CO2 + H2O + Mn^2+ + KOH}$$
The same reaction could be said for form... |
When a compound is synthesised or isolated, it needs to be characterised. This characterisation serves to determine whether something has been synthesised/isolated before and as a template for later generations to compare their synthesised/isolated compounds to the one you have.
Nowadays, one reports NMR and mass sp... |
What is the relationship between enthalpy of atomisation and enthalpy of sublimation? |
**tl; dr:** In the case of a metal, sublimation and atomization can be regarded as synonymous when atomization refers to the process of converting the solid into a dilute atomic gas. In particular, the end points (states) of the process should be identical.
There are usually conventions on what you call "enthalpy of... |
**tl; dr:** In the case of a metal, sublimation and atomization can be regarded as synonymous when atomization refers to the process of converting the solid into a dilute atomic gas. In particular, the end points (states) of the process should be identical.
There are usually conventions on what you call "enthalpy of... |
If I understood correct, the high energy of atomisation for d-block element comes from the ability to make many metallic bonds due to half electron filled d-orbitals, but it seems here that copper has no free d-orbitals yet has high enthalpy of atomisation? Is there a mistake in my understanding or is there a reason ... |
Why does copper have a high enthalpy of atomisation when it has a fully filled d sub shell? |
**tl; dr:** In the case of a metal, sublimation and atomization can be regarded as synonymous when atomization refers to the process of converting the solid into a dilute atomic gas. In particular, the end points (states) of the process should be identical.
There are usually conventions on what you call "enthalpy of... |
We know that we have to first break the metallic lattice to turn the metal into a gas and hence there should be some sort of relation between the two,
I am trying to do this question:
"The Eθ(M2+/M) value for copper is positive (+0.34V). What is possibly the reason for this? (Hint: consider its high ΔaHV and low Δhyd... |
What is the formula for vapor pressure of liquid related to surface tension of liquid? I know that if the surface tension increases, vapor pressure will decrease. Toluene evaporates faster than ethanol even though it is having more surface tension. How can I relate vapor pressure and surface tension between every solve... |
What is the formula for vapor pressure of liquid related to surface tension of liquid? |
We know that we have to first break the metallic lattice to turn the metal into a gas and hence there should be some sort of relation between the two.
I am trying to answer this question:
>The $E^θ(\ce{M^{2+}}/\ce{M})$ value for copper is positive ($\pu{+0.34 V}$). What is possibly the reason for this? (Hint: con... |
**tl; dr:** In the case of a metal, sublimation and atomization can be regarded as synonymous when atomization refers to the process of converting the solid into a dilute atomic gas. In particular, the end points (states) of the process should be identical.
There are usually conventions on what you call "enthalpy of... |
does1,2 cyclopentadione majorly exsist in enol form? And if it does then by what percentage does it exsist in enol form. Will it be more than other 1,3 diketones with active methylene groups forming 6 membered hydrogen bonds chelation?
|
does1,2 cyclopentadione majorly exsist in enol form? And if it does then by what percentage does it exsist in enol form. Will it be more than other 1,3 diketones with active methylene groups forming 6 membered hydrogen bonds chelation...whereas it forms only a 5 membered hydrogen bonding chelation?
|
Going off Linear Christmas's comment, I will note that the notation from the referenced article has become relatively common for inorganic chemists. I was introduced to this notation in Chapter 2 of
[*The Organometallic Chemistry of the Transition Metals*](https://books.google.com/books/about/The_Organometallic_Chemi... |
In light of [this question](https://chemistry.stackexchange.com/q/73614/7450) and its answers, I hope to get some insights into the $\mathrm{pH}$ of $\ce{LaCl3}$ in water and its $\mathrm{pH}$ relationship to $\ce{La(OH)3}$ precipitant's $\mathrm{p}K_\mathrm{a}$?
What can be done in order to prevent $\ce{LaCl3}$ fr... |
What is the pH and pKa relationship of LaCl3 in water and its precipitant La(OH)3? |
**tl; dr:** In the case of a metal, sublimation and atomization can be regarded as synonymous when atomization refers to the process of converting the solid into a dilute atomic gas. In particular, the end points (states) of the process should be identical.
There are usually conventions on what you call "enthalpy of... |
**tl; dr:** In the case of a metal, sublimation and atomization can be regarded as synonymous when atomization refers to the process of converting the solid into a dilute atomic gas. In particular, the end points (states) of the process should be identical.
There are usually conventions on what you call "enthalpy of... |
To what extent does 1,2-cyclopentadione exist in enol form? Will it be more than for 1,3 diketones? 1,3-Diketone with active methylene groups can form hydrogen bonds with a 6-membered ring structure. 1,2-cyclopentadione could also form hydrogen bonds, but it forms only a 5-membered ring.
|
I was watching an online lecture on Decarboxylation by Soda Lime and the first few examples were straight forward but after a while a felt that the questions couldn't simply have one effect and maybe other factors should also come into consideration as complexity of structures increases.
[![REAGENT][1]][1]
In the a... |
Is the following product feasible? |
I was watching an online lecture on Decarboxylation by Soda Lime and the first few examples were straight forward but after a while a felt that the questions couldn't simply have one effect and maybe other factors should also come into consideration as complexity of structures increases.
[![REAGENT][1]][1]
In the a... |
If one were to take 1 mole of pure liquid Calcium Chloride (at 600 C) and bombard it with 7.65 * 10^14 Ci (2.83 * 10^25 particles) of x-rays (75 keV), how the calcium chloride become chemically altered in anyway? Would the radiation cause the calcium and/or chloride ions to further ionize into a form that would not bon... |
I was watching an online lecture on decarboxylation by soda lime and the first few examples were straight forward but after a while a felt that the questions couldn't simply have one effect and maybe other factors should also come into consideration as complexity of structures increases.
[![REAGENT][1]][1]
In the a... |
I am trying to work out the absolute configuration around carbon atom 5 in 5-bromo-2-methyl-2-hexene. Could someone please let me know if my working is correct? Does the wedged bond from C4 to C5 affect the structure of the molecule and its configuration?
[![enter image description here][1]][1]
[1]: https://i... |
I have this question we are given 'x' grams of benzene and 'y' grams of toulene, it is said that the vapour pressure of benzene is 75mmHG and that of toulene is 22mmHG and we are supposed to find mole fraction in vapour state, what I do not understand is how different states can have different values for mole fraction?... |
How is molefraction of a solution different in vapour state vs in solution vs vapour-liquid equilibrium? |
I was watching an online lecture on decarboxylation by soda lime and the first few examples were straight forward but after a while a felt that the questions couldn't simply have one effect and maybe other factors should also come into consideration as complexity of structures increases.
[![REAGENT][1]][1]
In the a... |
Why is it the case that For Jahn-Teller effects to occur in transition metals there must be degeneracy in either the t2g or eg orbitals? |
I am trying to work out the absolute configuration around carbon atom 5 in 5-bromo-2-methylhex-2-ene. Could someone please let me know if my working is correct? Does the wedged bond from C4 to C5 affect the structure of the molecule and its configuration?
[![enter image description here][1]][1]
[1]: https://i... |
If one were to take $\pu{1 mol}$ of pure liquid Calcium Chloride (at $\pu{600 ^\circ C}$) and bombard it with $\pu{7.65 \times 10^{14} Ci}$ ($\pu{2.83 \times 10^25 particles}$) of x-rays ($\pu{75 keV}$), how the calcium chloride become chemically altered in anyway? Would the radiation cause the calcium and/or chloride ... |
I am a novice in chemistry.
I don’t understand the way Lewis structure and how electrons are shared between elements.
For instance [![enter image description here][1]][1]
As we know, Oxygen has six valence electrons that means it has **3 lone pairs**.
So when oxygen wants to form a covalent bond, one of its val... |
I have a conceptual physical chemistry question here.
>A thermos bottle containing milk is shaken vigorously. Consider the milk as the system. Will the temperature rise as a result of the shaking?
My answer to this is $\mathrm{yes}$, but i'm having trouble finding an equation that explains this result.
The be... |
I have a conceptual physical chemistry question here.
>A thermos bottle containing milk is shaken vigorously. Consider the milk as the system. Will the temperature rise as a result of the shaking?
My answer to this is yes, but I'm having trouble finding an equation that explains this result.
The best i have i... |
The trigonal bipyramidal shape of $\ce{PCl5}$ is indeed the lowest energy conformation.
I have had a very hard time figuring out what your description of the structure meant and I am still not convinced I have actually understood correctly. However I was trying to model it in my head I either arrived at a variety o... |
The reaction between ammonia and hydrogen chloride to give ammonium chloride is a neutralization reaction, since ammonia acts as a base and hydrogen chloride acts as an acid.
The reaction is usually written as:
\begin{gather*}
NH_3+HCl→NH_4Cl
\end{gather*}
When ammonia dissolves in water, the ammonium cation... |
Can acid-base reactions occur in a non-aqueous medium? |
During preparation of alkenes from alcohols, we generally heat it in the presence of Al2O3 but how does aluminium oxide help in the reaction? |
The reaction between ammonia and hydrogen chloride to give ammonium chloride is a neutralization reaction, since ammonia acts as a base and hydrogen chloride acts as an acid.
The reaction is usually written as:
\begin{gather*}
\ce{NH3 +HCl->NH4Cl}
\end{gather*}
When ammonia dissolves in water, the ammonium c... |
The reaction between ammonia and hydrogen chloride to give ammonium chloride is a neutralization reaction, since ammonia acts as a base and hydrogen chloride acts as an acid.
The reaction is usually written as:
$$\ce{NH3 + HCl -> NH4Cl }\tag{1}$$
When ammonia dissolves in water, the ammonium cation, its conju... |
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