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Order of second iozination energies of lithium,berillium,neon,carbon and boron? |
While passing a plane of symmetry through any compound inorganic or organic should it contain a minimum number of atoms or can it be passed without containing any atoms ?
 |
While passing a plane of symmetry through any compound inorganic or organic should it contain a minimum number of atoms or can it be passed without containing any atoms ?
 |
This is a follow-up to the question [here](https://chemistry.stackexchange.com/questions/92420/best-way-to-raise-ph-without-alkali-metal/92442?noredirect=1#comment170240_92442). There is an answer claiming that tetramethylammonium hydroxide (TMAH) is a suitable strong base that can be used instead of the usual alkalie... |
I was reading a book and it was mentioned that Co[Hg(SCN)4] is diamagnetic. I know that it is made up of Hg2+ and Co2+. Co2+ has 7 electrons which means that it should always have an unpaired electron but then why is this compound diamagnetic? Am I missing something? |
Is Co[Hg(SCN)4] diamagnetic? |
> How do I relate the reversibility that we study in chemical equilibrium to that we study in thermodynamics?
I think I now understand what you're trying to say. The root of your problem is that the word "reversible" in chemical equilibrium is **different** from "reversible" in thermodynamics. They're not **same** a... |
I was reading a book and it was mentioned that $\ce{Co[Hg(SCN)4]}$ is diamagnetic. I know that it is made up of $\ce{Hg2+}$ and $\ce{Co2+}$. $\ce{Co2+}$ has 7 electrons which means that it should always have an unpaired electron but then why is this compound diamagnetic? Am I missing something? |
I was reading a book and it was mentioned that $\ce{Co[Hg(SCN)4]}$ is diamagnetic. I know that it is made up of $\ce{Hg^2+}$ and $\ce{Co^2+}$. $\ce{Co^2+}$ has 7 electrons which means that it should always have an unpaired electron but then why is this compound diamagnetic? Am I missing something? |
Cobalt is the counter-ion here. When checking diamagnetism or paramagnetism, you have to instead check the metal ion inside the coordination sphere, which in this case is $\ce{Hg^2+}$. See your mistake?
And as a hint, note that $\ce{Hg^2+}$ will have a $\ce{3d^10}$ electronic configuration.
**PS:** I find it surp... |
I understand that standard heat of atomization is the amount of heat energy required to produce one mole of gaseous atoms from the element in its standard state.
As with other types of units, it is also stated in terms of $\pu{(magnitude) kJ mol^-1}$. However, consider this situation - which is representative of the... |
Aromaticity makes a cyclic compund more stable. Here, 1 and 3 are aromatic since they follow Huckels rule(Or am I wrong here?). So, I thought maybe 3 is most stable followed by 1, then followed by 2 and 4(I dont know which is more stable out of 2 a... |
I understand that standard heat of atomization is the amount of heat energy required to produce one mole of gaseous atoms from the element in its standard state.
As with other types of units, it is also stated in terms of $\pu{(magnitude) kJ mol^-1}$. However, consider this situation - which is representative of the... |
>Here, 1 and 3 are aromatic since they follow Huckels rule(Or am I wrong here?
Yes you're wrong over here for applying the Huckel's rule the compound must be a closed circuit of delocalized electrons. In both the cases the circuits are not closed
***
If you're not aware of [Conjugation](https://en.m.wikip... |
>Here, 1 and 3 are aromatic since they follow Huckels rule(Or am I wrong here?
Yes you're wrong over here, for applying the Huckel's rule the compound must be a closed circuit of delocalized electrons. In both the cases the circuits are not closed
***
If you're not aware of [Conjugation](https://en.m.wiki... |
This is (alkanesulfinyl)benzene:
[![enter image description here][1]][1]
I didn't draw it, but we know that the sulphur atom also has a lone pair. So, the sulphur atom can *increase* electron density in the ring by donating a lone pair. However, oxygen can also *withdraw* electron density from the ring by pulling... |
**Question**
>Rank the following radicals in order of decreasing stability
Why does the phenyl shift happen preferent... |
Do amides from primary or secondary amines ever oxidize to a double-bond on the nitrogen? For example, like from an $\mathrm{R \bbox[yellow]{\color{red}{-}}(NH)-(C=O)-R'}$ to an $\mathrm{ R \bbox[yellow]{\color{red}{=}}N-(C=O)-R'}$?
Seems like a favorable product, given the creation of that conjugated pi-bonded syst... |
**Definition from [Wikipedia][1]**:
> Organosulfur compounds are organic compounds that contain sulfur. They are often associated with foul odors, but many of the sweetest compounds known are organosulfur derivatives, e.g., saccharin. Nature abounds with organosulfur compounds—sulfur is essential for life.
> Sulf... |
(Please note, I am not simply asking, "Is the conjugate of a strong acid a weak base?" I'm asking about the contradictory ways those terms seem to be used.)
I was revisiting strong/weak acids/bases to help some high school chemistry students and found a lot of apparent contradictions in the way that sources use the... |
Is there a terminology contradiction about whether the conjugate of a strong acid is a "weak base"? |
Do amides from primary or secondary amines ever oxidize to a double-bond on the nitrogen? For example, like from an R-(NH)-(C=O)-R' to an R=N-(C=O)-R' ?
Seems like a favorable product, given the creation of that conjugated pi-bonded system! But, I can't seem to find any references to such a reaction (perhaps it's just... |
Do amides from primary or secondary amines ever reduce to a double-bond on the nitrogen? For example, like from an R-(NH)-(C=O)-R' to an R=N-(C=O)-R' ?
Seems like a favorable product, given the creation of that conjugated pi-bonded system! But, I can't seem to find any references to such a reaction (perhaps it's just ... |
Do amides reduce to double-bonds? |
Do amides from primary or secondary amines ever oxidize to a double-bond on the nitrogen? For example, like from an $\mathrm{R \bbox[yellow]{\color{red}{-}}(NH)-(C=O)-R'}$ to an $\mathrm{ R \bbox[yellow]{\color{red}{=}}N-(C=O)-R'}$?
Seems like a favorable product, given the creation of that conjugated pi-bonded syst... |
Do amides oxidize to double-bonds? |
Please help me with any/all of the cases below. In the following cases, the named method and basis set are not suitable for the chemical systems. Why aren't they? Could you suggest a suitable method/basis set for each?
---
### 1. MP2/6-31G(d) for the calculation of reaction energy of the reaction below (H2C: shou... |
This is a great question and I love it. Thank you for taking the time to not only post the question but each attempted response. I will try to address the parts of this question that I can at the moment. I will list, in order, your attempted answer along with my response.
----------
> 1. Carbene H2C: has two s... |
In the news it was announced that anyone who might have been exposed in the recent Salisbury nerve agent incident should wash any potentially contaminated clothing as normal using regular detergent and water; other personal items can be cleaned with wipes.
The agent in question (identified only as [Novichok][1], a f... |
Recently I was studying salts and my professor provided a list of cations which are considered neutral in salts: $Cl^-$, $Br^-$, $I^-$, $NO_3^-$, $ClO_4^-$.
Now I'm looking at this and I realized the list seems to be almost identical to list of strong acids: $HCl$, $HBr$, $HI$, $HNO_3$, $HClO_4$, $H_2SO_4$.
Is th... |
Neutral anions in salts and strong acids are similar - is it a coincidence? |
Recently I was studying salts and my professor provided a list of anions which are considered neutral in salts: $\ce{Cl-}$, $\ce{Br-}$, $\ce{I-}$, $\ce{NO_3^-}$, $\ce{ClO_4^-}$.
Now I'm looking at this and I realized the list seems to be almost identical to a list of strong acids: $\ce{HCl}$, $\ce{HBr}$, $\ce{HI}$, ... |
**Tetramethylammonium hydroxide**
This is a strong base like NaOH.
See [Behavior of Polyethylene Oxide Based Nonionic Surfactants
in Silicon Processing Using Alkaline Solutions][1] *J. Electrochem. Soc.* 1995 volume 142, 621-627:
>alkaline cleaning solutions based on quarternary ammonium hydroxides such... |
[TETRAMETHYLAMMONIUM HYDROXIDE][3] *Journal of the Chemical Society* 87 (1905): 955-961:
>Practically the preparation of tetramethylammonium hydroxide
fiom its salts resolves itself into a question of solubility as follows.
In general, the equation
>$$\ce{NMe4X + MOH = NMe4OH + MX}$$
>will represent a r... |
[TETRAMETHYLAMMONIUM HYDROXIDE][3] *Journal of the Chemical Society* 87 (1905): 955-961:
>Practically the preparation of tetramethylammonium hydroxide
from its salts resolves itself into a question of solubility as follows.
In general, the equation
>$$\ce{NMe4X + MOH = NMe4OH + MX}$$
>will represent a r... |
I'm trying to work out whether this [![molecule is chiral:][1]][1]
It is my understanding that the sulfur is sp2 hybridised. Why is this? The central sulfur atom is bound to 3 atoms and then has a lone pair, so surely it is sp3 hybridised?
Or does it become sp2 hybridised so the empty p orbital allows for e... |
Can a molecule be achiral whilst it's resonance form chiral? |
When looking at different chemicals, I come across the 'preferred IUPAC name' and the 'systematic IUPAC name'. I've noticed that when I name chemicals, I name them by their 'systematic IUPAC name', as I've been taught to name them using this system.
When is the 'preferred IUPAC name' used? I sometimes come across i... |
[TETRAMETHYLAMMONIUM HYDROXIDE][1] *Journal of the Chemical Society* 87 (1905): 955-961:
>Practically the preparation of tetramethylammonium hydroxide
from its salts resolves itself into a question of solubility as follows.
In general, the equation
>$$\ce{NMe4X + MOH = NMe4OH + MX}$$
>will represent a r... |
Recently I was studying salts and my professor provided a list of anions which are considered neutral in salts (that is, they do not change the $\mathrm{pH}$ of an aqueous solution when added as a salt): $\ce{Cl-}$, $\ce{Br-}$, $\ce{I-}$, $\ce{NO_3^-}$, $\ce{ClO_4^-}$.
Now I'm looking at this and I realized the list... |
This is a follow-up to the question [here](https://chemistry.stackexchange.com/questions/92420/best-way-to-raise-ph-without-alkali-metal/92442?noredirect=1#comment170240_92442). There is an answer claiming that tetramethylammonium hydroxide (TMAH) is a suitable strong base that can be used instead of the usual alkalie... |
I would like to know how to obtain the following molecule, whose technical name should be something like *N,N-dimethylindol-3-ylglyoxylamide* (let's call it *DMIG* for short)
[![DMIG][1]][1]
One of the constraints being that I'd like to limit myself to compounds that are relatively easy/cheap (and, of course, leg... |
I refer you to [this][1] set of presentation slides. On slide 8, the author explains the preference for the staggered conformation of ethane by saying that there is a favourable hyperconjugative interaction between $\sigma^{}_{C-H}$ of the C-H bond in one methyl group and $\sigma^{*}_{C-H}$ of another C-H bond in the o... |
I need to compare the acidic strength in these molecules:
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/Ddn64.png
My Approach:
In compound I: Removing a proton would lead to conjugation between -ve charge, pi bond and lone pair of O. Moreover the inductive effect due to 'O' will... |
The degree of dissociation of the reactant at $1 atm$ is $20%$ (percent) as follows :
$$2NH_{3}⇆N_{2} + 3H_{2} $$
I follow two ways but end in two different answers...
> Here , I assume that initial amount of reactant mole is $2$ and this rod products us $0$ . Then I take the amount of ammonia in equilibr... |
How do London Dispersion Forces and Dipole-Dipole forces exist at the same time between polar molecules? |
London Dispersion Forces and Dipole-Dipole forces together? |
>The degree of dissociation of the reactant at $\pu{1 atm}$ is 20% as follows :
$$\ce{2NH_{3} <=> N_{2} + 3H_{2}} $$
I follow two ways but end in two different answers...
Here , I assume that initial amount of reactant mole is 2 and this rod products us 0 . Then I take the amount of ammonia in equilibrium... |
>The degree of dissociation of the reactant at $\pu{1 atm}$ is 20% as follows :
$$\ce{2NH3 <=> N2 + 3H2} $$
I follow two ways but end up with two different answers.
Here, I assume that initial amount of reactant mole is 2 and this rod produces 0. Then I take the amount of ammonia in equilibrium to be $\ma... |
Very pure hydrogen (99.9) can be made by which of the following process ?
(A)Electrolysis of water
(B)Reaction of salt like hydrides with water.
As per my knowledge the answer should be (B) but I am a bit confused and not exactly sure about the answer.
*Any explanation for the correct answer would be appreciated* |
How can we obtain very pure hydrogen? |
Using sodium bicarbonate as a deodorant sometimes can produce a strong ammonia smell. Is there some obvious chemical explanation for this? |
Is there any obvious relation between sodium bicarbonate and ammonia; (how) can sodium bicarbonate be involved in producing ammonia? |
This has a simpler answer than you expect. First of all, your reasoning is wrong because inductive effect is much less dominant than conjugation of electron pairs. So, if the latter is unequal in both cases, we should first prioritize it over inductive effects.
> Removing a proton(from the carbon adjacent to the pi ... |
Let's look at the definitions from Gold Book:
**Absorption**:
> The process of one material (absorbate) being retained by another (absorbent); this may be the physical solution of a gas, liquid, or solid in a liquid, attachment of molecules of a gas, vapour, liquid, or dissolved substance to a solid surface by ph... |
What is the difference between dissolution and absorption? |
Can someone tell me why - in experiments to observe corrosion of iron nails - we often use a preparation of agar gel (with $\ce{NaCl}$, phenolphthalein, etc.) instead of an aqueous solution? |
I am trying to make a new force field in amber for a novel compound including Boron (which does not exist in gaff).
For this, I calculated freq and I found bond-force-constants but I couldn't find force constants for **angles**.
For example I tested H2O: I calculated H2O frequencies in gaussian and I got constant ... |
Force Constants for Angles From Gaussian To Amber Which value shuold put in the matrix equation? |
What's the reaction of isopropyl chloride with sodium acetate? (The solvent is acetic acid)
Is it SN¹ or SN²?
My thoughts:
1. It's not that difficult to approach isopropyl chloride's carbon, for there isn't much steric crowding. It's just a 2° RX with two methyl groups. This favours SN².
2. 2°RX, here in this case... |
What's the reaction of isopropyl chloride with sodium acetate? (The solvent is acetic acid)
Is it S<sub>N</sub>1 or S<sub>N</sub>2?
My thoughts:
1. It's not that difficult to approach isopropyl chloride's carbon, for there isn't much steric crowding. It's just a 2 degree alkyl halide with two methyl groups. Th... |
Does isopropyl chloride undergo SN1 or SN2 with sodium acetate? |
What's the reaction of isopropyl chloride with sodium acetate? (The solvent is acetic acid)
Is it S<sub>N</sub>1 or S<sub>N</sub>2?
My thoughts:
1. It's not that difficult to approach isopropyl chloride's carbon, for there isn't much steric crowding. It's just a 2 degree alkyl halide with two methyl groups. Th... |
What's the reaction of isopropyl chloride with sodium acetate? (The solvent is acetic acid)
Is it S<sub>N</sub>1 or S<sub>N</sub>2?
My thoughts:
1. It's not that difficult to approach isopropyl chloride's carbon, for there isn't much steric crowding. It's just a 2 degree alkyl halide with two methyl groups. Th... |
Let's look at the definitions from Gold Book:
**Absorption**:
> The process of one material (absorbate) being retained by another (absorbent); this may be the physical solution of a gas, liquid, or solid in a liquid, attachment of molecules of a gas, vapour, liquid, or dissolved substance to a solid surface by ph... |
[![enter image description here][1]][1]
I am asked to give the type of reaction (S<sub>N</sub>1, S<sub>N</sub>2 or acid-base reaction) for the following reactions. I know that both $\ce{MeOH}$ and $\ce{EtOH}$ polar protic solvents, so because the first is an S<sub>N</sub>2 reaction shouldn't the second reaction be t... |
Let's look at the definitions from Gold Book:
**Absorption**:
> The process of one material (absorbate) being retained by another (absorbent); this may be the physical solution of a gas, liquid, or solid in a liquid, attachment of molecules of a gas, vapour, liquid, or dissolved substance to a solid surface by ph... |
Follow this paper,
<Structural analysis of humins formed in the Brønsted acid catalyzed dehydration of fructose>
[Structural analysis of humins formed in the Brønsted acid catalyzed dehydration of fructose ](http://pubs.rsc.org/en/Content/ArticleLanding/2018/GC/C7GC03054A#!divAbstract)
They explained "humins are s... |
What is spatially and chemically heterogeneous materials? |
Is there any logical reasoning behind the migratory aptitude for different groups in Baeyer-Villiger Oxidation?
Like in pinacol-pinacolone rearrangement, hydride ion is a better migrating group than an aryl which is better than an alkyl group. But why isn't this kind of order in Baeyer-Villiger Oxidation? |
I have done a biosorption study using a protein as a biosorbent and six different concentrations of $\ce{Pb}$ ions. I need to show the efficiency of the biosorbent, I was told to use the Langmuir isotherm to represent these results. Thus far, I
have plotted a graph of $q$ vs. $C_\mathrm f$ using the formula
$$q =... |
>The degree of dissociation of the reactant at $\pu{1 atm}$ is 20 % as follows:
$$\ce{2NH3 <=> N2 + 3H2} $$
I follow two ways but end up with two different answers.
Here, I assume that initial amount of reactant mole is 2 and this rod produces 0. Then I take the amount of ammonia in equilibrium to be $2-2\a... |
**Point 3)**
Why some electrons are $\mathrm{\sigma}$-bonding, $\mathrm{\pi}$-bonding or non-bonding is easier to understand if you first think about the orbitals involved. I'll discuss it in terms of hybridisation.
The central $\ce{C}$ atom has an $\mathrm{sp^2}$ hybridisation (corresponding to a trigonal planar... |
When propane reacts with chlorine, we will mostly (theoretically) get an isomer with a chlorine on the end. ($CH_3-CH_2-CH_2Cl$). However, when propane reacts with bromine, we will mostly get an isomer with bromine attached to the second carbon ($CH_3-CHBr-CH_3$). Could anyone please explain why this happens? |
When propane reacts with chlorine, we will mostly (theoretically) get an isomer with a chlorine on the end. ($\ce{CH_3-CH_2-CH_2Cl}$). However, when propane reacts with bromine, we will mostly get an isomer with bromine attached to the second carbon ($\ce{CH_3-CHBr-CH_3}$). Could anyone please explain why this happens? |
Is the shorthand electron configuration of Br- just [Kr]?
Also what about Ca2+ is it just [Ar] and Na+ just [He] 2s2 2p4? |
Is the shorthand electron configuration of Br- just [Kr]? |
[Here is a Pourbaix diagram of iron.][1] The line between Fe and Fe2+ is there because the Potential Fe/Fe2+ is -0.44V. The same applies for Fe2+/Fe3+ with 0.77V. But Fe/Fe3+ is -0.03V, but it's not on the graph as a line. How do I know which species have a line, and which don't? And if I'm drawing a graph, how do I kn... |
**Here is a Pourbaix diagram of iron:**
![Pourbaix diagram of iron][1]
The line between $\ce{Fe}$ and $\ce{Fe^2+}$ is there because the Potential $\ce{Fe/Fe^2+}$ is -0.44V. The same applies for $\ce{Fe^2+/Fe^3+}$ with 0.77V. But $\ce{Fe/Fe^3+}$ is -0.03V, but it's not on the graph as a line. How do I know which s... |
Is the shorthand electron configuration of $\ce{Br-}$ just $\ce{[Kr]}$?
Also what about $\ce{Ca^2+}$—is it just $\ce{[Ar]}$? And, is $\ce{Na+}$ just $\ce{[Ne]}$? |
I'm a teaching assistant on a first year course on Introduction to Thermodynamics based on the book "Molecular Driving Forces" by Dill & Bromberg.
There's a question which asks the students to derive the following relation between S, V and N:
$S(V,N) = Nkln(V)$
A simple solution that is hinted is to use the di... |
I have been studying chemistry for a while but I feel a total noob about it, so please be clear when answering.
I was studying and I encountered this exercise:
*Write the reaction between copper and concentrated nitric acid.*
Now, I know what copper is and also what nitric acid is, but how do I figure out that t... |
How to write a reaction that you have never seen? |
I have the following equation, already written, with a few coefficients to write.
$2MnO^-_4 + a H_2O_2 + b H^+ -> 2Mn^{2+} +cO_2 + dH_2O$
I have put a= 1, b=6, c=3 and d=4.
The number of atoms and the charges appear balanced to me. It is wrong, so where am I mistaking? |
How to balance this manganese peroxide reaction with hydrogen peroxide? |
Does nitric acid release hydrogen only when reacting with Mg and Mn? |
I am trying to make a new force field in AMBER for a novel compound including Boron (which does not exist in GAFF).
For this, I calculated freq and I found bond-force-constants but I couldn't find force constants for **angles**.
For example I tested $\ce{H2O}$: I calculated $\ce{H2O}$ frequencies in Gaussian and I ... |
Force Constants for Angles From Gaussian To AMBER: which value should I put in the matrix equation? |
I am trying to make a new force field in AMBER for a novel compound including boron (which does not exist in GAFF). For this, I calculated freq and I found bond force constants but I couldn't find force constants for **angles**.
For example I tested $\ce{H2O}$: I calculated $\ce{H2O}$ frequencies in Gaussian and I g... |
I would like to simulate a layer of graphene on a solid substrate, say Cu or quartz. I'm interested in their binding energy and other physical or chemical properties. However, their periods do not match each other, so if I want to use some standard DFT package like VASP or Quantum Expresso, I cannot use a single period... |
I have the following equation, already written, with a few coefficients to write.
$\ce{2MnO^-_4 + a H_2O_2 + b H^+ -> 2Mn^{2+} +cO_2 + dH_2O}$
I have put a = 1, b =6, c =3 and d =4.
The number of atoms and the charges appear balanced to me. It is wrong, so where am I mistaking? |
I have the following equation, already written, with a few coefficients to write.
$\ce{2MnO^4- + a H2O2 + b H+ -> 2Mn^2+ +c O2 + dH2O}$
I have put a = 1, b = 6, c = 3 and d = 4.
The number of atoms and the charges appear balanced to me. It is wrong, so where am I mistaking? |
I have the following equation, already written, with a few coefficients to write.
$\ce{2MnO4^- + a H2O2 + b H+ -> 2Mn^2+ +c O2 + dH2O}$
I have put a = 1, b = 6, c = 3 and d = 4.
The number of atoms and the charges appear balanced to me. It is wrong, so where am I mistaking? |
I have been studying chemistry for a while but I feel a total noob about it, so please be clear when answering.
I was studying and I encountered this exercise:
> Write the reaction between copper and concentrated nitric acid.
Now, I know what copper is and also what nitric acid is, but how do I figure out that... |
This is a follow-up to the question [here](https://chemistry.stackexchange.com/questions/92420/best-way-to-raise-ph-without-alkali-metal/92442?noredirect=1#comment170240_92442). There is an answer claiming that tetramethylammonium hydroxide (TMAH) is a suitable strong base that can be used instead of the usual alkalie... |
I think that as it is diazosalt it shouldn't be stable at room temperature. But it is stable. How is that possible? |
Why is benzenediazonium fluoroborate stable at room temperature? |
Why is benzenediazonium fluoroborate water insoluble and stable at room temperature? |
I think that as it is diazosalt it shouldn't be stable at room temperature. But it is stable. How is that possible?
And it is ionic hence insoluble in water.
Why? |
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