instruction stringlengths 15 21.8k |
|---|
Does it make sense to differentiate the Arrhenius equation with respect to temperature? |
2 moles of an ideal gas are in a closed system with a temperature of $25°C$.
The gas is cooled under constant **pressure** and afterwards heated gas under constant **volume**.
During the cooling process the gas has lost $1000J$ of heat to the environment.
It is known that the molar heat capacity of the gas is ... |
2 moles of an ideal gas are in a closed system with a temperature of $25°C$.
The gas is cooled under constant **pressure** and afterwards heated gas under constant **volume**.
During the cooling process the gas has lost $1000J$ of heat to the environment.
It is known that the molar heat capacity of the gas is ... |
Does anyone know if the presence of an electric field can help to reduce water adhesion to a surface? |
> *"An oxidizing acid is a Brønsted acid that is a strong oxidizing
> agent. All Brønsted acids can act as oxidizing agents, because the
> acidic proton can be reduced to hydrogen gas."*
>
but what does *oxidizing* have to do with *hydrogen*?
isn't it about *oxygen*?
like how *iron* becomes *iron oxide*... |
what does *oxidizing* have to do with *hydrogen*? |
The question didn't specify that which process was the given molar heat capacity was specified for. So we will assume that it is molar heat capacity for the first process. The first process is isobaric so $$q=nC_p\Delta T$$
You calculated $\Delta T$ correctly. The only mistake you did was assume that the gas was mo... |
> 2 moles of an ideal gas are in a closed system with a temperature of $25\ \mathrm{^\circ C}$.
>
> The gas is cooled under constant **pressure** and afterwards heated gas under constant **volume**.
>
> During the cooling process the gas has lost $1000\ \mathrm J$ of heat to the environment.
>
> It is known that ... |
The question didn't specify that which process was the given molar heat capacity was specified for. So we will assume that it is molar heat capacity for the first process. The first process is isobaric so $$q=nC_p\,\Delta T$$
You calculated $\Delta T$ correctly. The only mistake you did was assume that the gas was ... |
The question didn't specify that which process was the given molar heat capacity was specified for. So we will assume that it is molar heat capacity for the first process. The first process is isobaric so $$q=nC_p\,\Delta T$$
You calculated $\Delta T$ correctly. The only mistake you did was assume that the gas was ... |
Our instructor has lately been teaching us about different types of cations namely-Classical, Non-Classical, Resonance stabilized (**R.S.C**) & Octet complete cation (**O.C.C**) & how O.C.C is more stable than a R.S.C .
<br>One thing I did not get isn't donating lone pair like in the below given example too is resona... |
Why is an Octet Complete Cation more stable than a Resonance Stabilized Cation? |
My understanding is that:
* microplastics are short fragments of previously long polymer chains;
* wildfire smoke largely consists of incompletely burned organic materials such as wood. Wood burns by heat first breaking long polymer chains into small fragments, which then ignite (or not).
So ... it sounds like t... |
It's a simple matter of energy conservation. Here no heat can flow between surrounding and system. If work is done by the system, where do you think that energy comes from?
When a gas does expansion work, a part of kinetic energy is used up in doing work and average kinetic energy of the gas decrease. I ask you, wha... |
> An oxidizing acid is a Brønsted acid that is a strong oxidizing agent.
> All Brønsted acids can act as oxidizing agents, because the acidic
> proton can be reduced to hydrogen gas."
The whole sentence is written in a very convoluted fashion, and it is partially wrong as well. Someone should improve this Wikipedi... |
#TL;DR;
- Oxidation States are useful tools used in nomenclature, redox chemistry etc.
- There are a few simplistic rules to determine the oxidation state of elements in an atom; but they're not applicable to all the cases.
- There are instances where the assignment of oxidation state isn't useful, or where the o... |
Historically speaking, _potassium_ derives from _pot ash_ and now [_potash_][1] when -- if there were no geologic sources of $\ce{K2CO3}$ -- woods were burnt in a pot. The addition of water will dissolve $\ce{K2CO3}$ and other high soluble matter, but not the ash. According to [wikipedia][2], the addition of amine ma... |
I have 5 pounds of loose activated bamboo charcoal that I am using as an odor absorber. When I need to recharge it, I would like to heat it to 100 degrees celsius. How long does it need to remain at this temperature to recharge, that is, de-adsorb anything on its surface? |
What is the duration of time needed if heating activated carbon at 100 degrees celsius to recharge? |
I'm reading a book that covers the basics of electrical theory and I'm at a chapter that discusses the concept of a primary cell. The author includes the redox reactions that take place in a primary cell when it is charging/discharging.
The primary cell is comprised of an anode (composed of PbO<sub>2</sub>) and a c... |
What reaction would take place on an electrode in a primary cell if it were charged and the other electrode removed? |
I'm reading a book that covers the basics of electrical theory and I'm at a chapter that discusses the concept of a primary cell. The author includes the redox reactions that take place in a primary cell when it is charging/discharging.
The primary cell is comprised of an anode (composed of PbO<sub>2</sub>) and a c... |
I have read that while comparing atoms in a **row** we compare their electronegativities to know which atom would better stabilize a negative charge on it, and for atoms in a **column** we compare their sizes. Why is that so? Like, for example if we consider Nitrogen and Oxygen (which are same **row** elements), why ca... |
There seems to be a priority order that has to be followed while naming an organic compound with more than one functional group , according to IUPAC rules. I want to know if there is a basis on which this priority list has been made, or is it just arbitrarily ordered.
I have tried to connect the dots but failed, fir... |
Is the precedence of functional groups used in IUPAC naming arbitrary? |
The question didn't specify which process the given molar heat capacity was specified for. So we will assume that it is molar heat capacity for the first process. The first process is isobaric so $$q=nC_p\,\Delta T$$
You calculated $\Delta T$ correctly. The only mistake you did was assume that the gas was monoatomi... |
I'm looking for a liquid that can remove copper corrosion (oxides and basic carbonates - the black and green stuff) off copper piping.
The corrosion will be located on the inside of the pipe, in hard-to-reach areas, so ideally I should be able to just pour the liquid in, leave it for a while, and just flush it out w... |
What (stored-as-solids) acids/liquids can clean corroded copper? |
I'm sorry if this is a really super basic question. I am looking at the potential curves of a diatomic molecule in a book , and to plot them. I google the molecule and got to the NIST website, there I get diatomic mass and constants for each state, such as:
- Te - minimum electronic energy (cm-1)
- ωe - vib... |
how to obtain potential curves from database? |
It is common knowledge that aluminum is relatively resistant to corrosion due to its tough oxide layer. The ultrathin (1 nm even) layer is impervious to water and oxygen. What I can't figure out is, why? What makes $\ce{Al2O3}$ so strong compared to $\ce{Na2O}$ or $\ce{MgO}$? My theory is that the aluminum oxide molecu... |
Why is aluminum oxide resistant to corrosion? |
Are you asking how to take code developed to find the MFE (minimum free energy) structure of a single protein, and modify it to instead determine the structure of a two-protein complex?
Or are you asking if you can use this code, as is, to fold a concatenated combination of the two proteins, and in turn use this r... |
(This is in the context of macromolecular X-ray crystallography.)
From [Lamb et al. 2015][1]:
> Model bias is the result of how maps are calculated: because the
phase estimates for the calculation come from the model, maps will
tend to show electron density for an atom in the model whether it is
truly there or... |
Are crystallographic omit maps only used with molecular replacement? |
(This is in the context of macromolecular X-ray crystallography.)
From [Lamb et al. 2015][1]:
> Model bias is the result of how maps are calculated: because the
phase estimates for the calculation come from the model, maps will
tend to show electron density for an atom in the model whether it is
truly there or... |
> An oxidizing acid is a Brønsted acid that is a strong oxidizing
> agent. All Brønsted acids can act as oxidizing agents, because the
> acidic proton can be reduced to hydrogen gas.
(source: [Wikipedia][1])
But what does *oxidizing* have to do with *hydrogen*? Isn't it about *oxygen*?
Like how *iron* become... |
What does *oxidizing* have to do with *hydrogen*? |
The answer above is perfectly fine. There is another way to see it. It is very important to realize what is a "system" and a "surrounding", what changes when we talk about Entropy and other state functions? when we talk about Entropy, we say "The total change in Entropy of Universe is never negative, it can be either z... |
(This is in the context of macromolecular X-ray crystallography.)
From [Lamb et al. 2015][1]:
> Model bias is the result of how maps are calculated: because the
phase estimates [of the structure factor] for the calculation come from the model, maps will
tend to show electron density for an atom in the model whe... |
> MY textbook says : Real gases show Ideal Behavior under *low pressure ,high temperature.*
So I wanted to know what happens to real gases at *high pressure ,low pressure*
Do they also show ideal behavior under those conditions?
|
Under what conditions does Real Gases show Ideal Behaviour? |
I'm reading a book that covers the basics of electrical theory and I'm at a chapter that discusses the concept of a secondary cell. The author includes the redox reactions that take place in a primary cell when it is charging/discharging.
The secondary cell is comprised of an anode (composed of PbO<sub>2</sub>) and... |
What reaction would take place on an electrode in a secondary cell if it were charged and the other electrode removed? |
> in this case (of omitting a part), there would be an electron density (because the amplitudes are still there), just that it would be featureless
For each reflection, the structure factor $F_{hkl}$ gives the magnitude and phase resulting from interference of all atoms in the unit cell (see e.g. [this slide show][1... |
The following doesn't fit into a comments box.
- From the perspective of small molecule crystallography (say, ShelX), once you solved your model completely or completely enough to engage refining, you may recognize reflections leaving the straight line in the Fobs _vs._ Fcalc map. Within reason, it is possible to o... |
> [OP] ...if we don't have the phases (say for a part of a model), it just wouldn't get built even if we have the amplitudes for that part, right? Or is it that in this case (of omitting a part), there would be an electron density (because the amplitudes are still there), just that it would be featureless
For each r... |
I can't understand the electron count made on this page about Ozonolysis. (http://ursula.chem.yale.edu/~chem220/chem220js/STUDYAIDS/ozonolysis/Oz.html)
This is the specific part of the article:
[![Ozonide oxidation level][1]][1]
From my calculations the oxidation of an alkene to an ozonide is a 4 electrons oxidat... |
> [OP] ...if we don't have the phases (say for a part of a model), it just wouldn't get built even if we have the amplitudes for that part, right? Or is it that in this case (of omitting a part), there would be an electron density (because the amplitudes are still there), just that it would be featureless
For each r... |
Historically speaking, _potassium_ derives from _pot ash_ and now [_potash_][1] when -- if there were no geologic sources of $\ce{K2CO3}$ -- woods were burnt in a pot. The addition of water will dissolve $\ce{K2CO3}$ and other high soluble matter, but not the ash. According to [wikipedia][2], the addition of amine ma... |
First of all, I know that the reason for this is the bent structure of the molecule.
However, we were taught in my class that the dipole moment of a molecule is equal to the vector sum of the dipole moment of each bond in the molecule.
But Ozone only has bonds between two Oxygens, so why is the dipole moment of e... |
I'm reading a book that covers the basics of electrical theory and I'm at a chapter that discusses the concept of a secondary cell. The author includes the redox reactions that take place in a primary cell when it is charging/discharging.
The secondary cell is comprised of an anode (composed of PbO<sub>2</sub>) and... |
I am trying to fill a vial with as many immiscible liquids as possible so that they form many separate layers. I want to do this as a way to visualise how liquids with different refractive indexes flow past one another.
**TLDR** Is there some list or way of finding out which transparent liquids (at STP) I can mix i... |
It says: the rate of the chemical reaction is directly proportional to the product of the activities or concentrations of the reactants.
I can’t wrap my head around this statement. Could anyone explain it in other words please? |
D-glucose most common in nature and L-glucose is synthesized in the lab. I think that humans can't use L-glucose in their aerobic pathways so that they have not the same site to fill the active site of the enzyme but I am not satisfied. So why our cells can't use L-glucose? |
Does enzymes that digest D-glucose react with L-glucose? |
I'm looking for a liquid that can remove copper corrosion (oxides and basic carbonates - the black and green stuff) off copper piping.
The corrosion will be located on the inside of the pipe, in hard-to-reach areas, so ideally I should be able to just pour the liquid in, leave it for a while, and just flush it out w... |
This seems like it should be obvious but for some reason (my chemistry is very rusty) I'm having a hard time articulating why the hardboiled egg recipe in an instant pot should yield the same results regardless of altitude.
Questions:
1. Would I get the same results at altitude using the pressure cooker?
2. Why? o... |
If I hard boil eggs in a pressure cooker, will I get the same results regardless of altitude? |
D-glucose most common in nature and L-glucose is synthesized in the lab.
I know that humans can't use L-glucose in their aerobic pathways because it doesn't match the active site of the enzyme ...but I'd like to confirm and understand why.
Why can't our cells use L-glucose? |
Do enzymes that digest D-glucose react with L-glucose? |
D-glucose most common in nature and L-glucose is synthesized in the lab.
I know that humans can't use L-glucose in their aerobic pathways because it doesn't match the active site of the enzyme ...but I'd like to confirm and understand:
>Why can't our cells use L-glucose? |
> However, we were taught in my class that the dipole moment of a molecule is equal to the vector sum of the dipole moment of each bond in the molecule. But Ozone only has bonds between two Oxygens, so why is the dipole moment of each bond not equal to zero?
Chemical education is in such a sorry state. Why do they t... |
When water evaporates the hotter molecules leave and they take some heat with them. Which cools down what's left in the pot. You keep heating your pot and more molecules evaporate, which in turn cools down the pot more. When you just started to heat water - the amount of heat absorbed by the water is greater than the c... |
Take these two practice problems and their solutions from Ebbing (*8th ed*) that involve completing the molecular equation then writing the net ionic equation:
4.42a: $Ca(OH)_2(aq) + 2H_2SO_4(aq) \rightarrow$
soln: $$Ca(OH)_2(aq) + 2H_2SO_4(aq) \rightarrow 2H_2O(l) + Ca(HSO_4)_2(aq)$$
$$OH^-(aq) +2H^+(aq) +SO_4^... |
When writing the net ionic equation, if one of the products ionizes what is the most appropriate way to account for this in the answer? |
>When writing the net ionic equation, if one of the products ionizes, what is the most appropriate way to account for this in the answer?
Take these two practice problems and their solutions from Ebbing (*8th ed*) that involve completing the molecular equation, then writing the net ionic equation:
4.42a: $\ce{Ca(... |
![see image here]: https://i.stack.imgur.com/ZkDD0.png
I don't quite understand why these two hydrogens are the most acidic- from a hybridization perspective these are connected to a sp3 C (I thought the more s character, the more acidic). So why is it not any of the other hydrogens (connected to sp2 carbon)?
|
Why are these H the most acidic? |
[![enter image description here][1]][1]
I don't quite understand why these two hydrogens are the most acidic. From a hybridization perspective, these are connected to a $\mathrm{sp^3}$ carbon (I thought the more s character, the more acidic). So why is it not any of the other hydrogens (connected to $\mathrm{sp^2}$ ... |
[![cyclohexa-2,5-dien-1-one][1]][1]
I don't quite understand why these two hydrogens are the most acidic. From a hybridization perspective, these are connected to a $\mathrm{sp^3}$ carbon (I thought the more s character, the more acidic). So why is it not any of the other hydrogens (connected to $\mathrm{sp^2}$ carb... |
My apologies in advance if this is not the best forum for this kind of question.
Recently, I've bought a few non-anodized aluminium bread-baking forms, such as this one:
[![enter image description here][1]][1]
As you can see, there is already some discoloration on them when they come from the shop. My knowl... |
Is using oxidized aluminium baking forms safe? |
In our village lots of ash produced lot of it is thrown .so I want to extract pure potassium carbonate .However I am able to extract potassium compound and soluble compound by recrystallizing and evaporating .hence I found impurities the first test I do is electrolysis, during electrolysis there is presence of chlorine... |
In our village, lots of ash is produced which is thrown off. I want to extract pure potassium carbonate from that ash. I am able to extract the potassium compound and a soluble compound by recrystallizing and evaporating but I found impurities. The first test I performed is electrolysis. This test confirmed the presenc... |
How to extract pure potassium carbonate from ash? |
I think the title is clear enough . But I am rewriting the question for convenience.
>I just want to know that why aren't elements like magnesium, beryllium etc, with two valence electrons be stable like helium atom or why can't other elements become stable by completing duplet in the valence shell ? |
Why can't other elements become stable by completing duplet in their valence shell like helium atom does? |
We all know that hydrogen becomes stable by completing duplet and helium is stable since its valence shell has completed the duplet
>But I want to know that why aren't elements like magnesium, beryllium etc, with two valence electrons be stable like helium atom or why can't other elements become stable by comple... |
Why aren't elements with two valence shell electrons stable? |
Could you please help me understand the Wiki’s explanation of the rate of chemical reaction?
>It says: the rate of the chemical reaction is directly proportional to the product of the activities or concentrations of the reactants.
I can’t wrap my head around this statement. Could anyone explain it in other words... |
My textbook said that coordination complexes with weak field ligands require a larger wavelength for obtaining enough energy for electron transfer(and hence, the manifestation of a colour), but if E = hv(E is the energy, h is Planck's Constant and v is the frequency), then shouldn't the wave of higher frequency be need... |
In Concise Inorganic Chemistry (5th Edition) on page 196 , the primary valency of $[Co(NH_3)_5Cl]Cl_2$ is given to be 2.[![enter image description here][1]][1]
In other textbooks and in the [question][2] here, We get the idea that
>The primary valency of a compound is equal to its oxidation state.
In 'Inorga... |
First of all, I know that the reason for this is the bent structure of the molecule.
However, we were taught in my class that the dipole moment of a molecule is equal to the vector sum of the dipole moment of each bond in the molecule.
But ozone only has bonds between two oxygens, so why is the dipole moment of e... |
>A primary battery has the reaction:
$2$MnO$_2$ + Zn + $2$NH$_4$Cl $->$ Mn$_2$O$_3$ + Zn(NH$_3$)$_2$ + H$_2$O
>
> Write the half-cell reactions for the given equation.
I am having trouble understandning how you know which will be the oxidation reaction and which will be the reduction reaction. From what I have u... |
>A primary battery has the reaction:
$$\ce{2MnO2 + Zn + 2NH4Cl -> Mn2O3 + Zn(NH3)2 + H2O}$$
>Write the half-cell reactions for the given equation.
I am having trouble understanding how you know which will be the oxidation reaction and which will be the reduction reaction. From what I have understood I should assig... |
>A primary battery has the reaction:
$$\ce{2MnO2 + Zn + 2NH4Cl -> Mn2O3 + Zn(NH3)2Cl2 + H2O}$$
>Write the half-cell reactions for the given equation.
I am having trouble understanding how you know which will be the oxidation reaction and which will be the reduction reaction. From what I have understood I should as... |
Given that the fugacity of a substance is $f=Pe^{bT}$, how do I obtain the equation of state of the substance?
This is my approach, but I have not made good headway:
$$RT d (\ln f) = VdP \\
d(\ln f) = \frac{V}{RT} dP \\
bdT = \left( \frac{V}{RT} - \frac{1}{P}\right)dP$$
But what next? I see that
$$\left( \f... |
I would like to calculate the concentration of 10 µM unit in vitro to blood plasma unit ng/ml?
What formula do I need to use?
Do I need to use molecular weight? In my case, it is 314,47 g/mol for Cannabidiol
Can someone help? |
We all know that hydrogen becomes stable by completing duplet and helium is stable since its valence shell has completed the duplet
Still, other elements don't behave like that. I want to know that why aren't elements like magnesium, beryllium etc, with two valence electrons be unreactive like helium atom, or why... |
>A primary battery has the reaction:
$$\ce{2MnO2 + Zn + 2NH4Cl -> Mn2O3 + Zn(NH3)2Cl2 + H2O}$$
>Write the half-cell reactions for the given equation.
I am having trouble understanding how you know which will be the oxidation reaction and which will be the reduction reaction. From what I have understood I should as... |
Woah, that answer above me is very complicated. Im sure that it is also right, but let's explore a simpler way to look at this. Instead of thinking of elements becoming unreactive when their octet/duplet is filled, lets think about unreactivity in terms of noble gases. If we look at the noble gases on the periodic tabl... |
In accord with this forum's policy on not providing health advice, I will just comment on the chemistry surrounding any created Al3+ interacting with the superoxide radical anion (which is incidentally, present in the human body). As a source, here is a 2014 article by Tushar Kanti Das, et al, published in *Archives o... |
In accord with this forum's policy on not providing health advice, I will just comment on the chemistry surrounding any created Al3+ interacting with the superoxide radical anion (which is incidentally, present in the human body). As a source, here is a 2014 article by Tushar Kanti Das, et al, published in *Archives o... |
What is the chemical formula of GHEE (Indian butter)? Also, name the elements present and state the number of their atoms. |
What is the chemical formula of GHEE? |
The composition of ghee varies depending on the animal whose milk has been used. Ghee is a complex lipid of glycerides (majorly triglycerides), free fatty acids, phospholipids, sterols, sterol esters, fat soluble vitamins, carbonyls, hydrocarbons and carotenoids (only in ghee derived from cow milk).
[![enter image des... |
In Concise Inorganic Chemistry (5th Edition) on page 196 , the primary valency of $\ce{[Co(NH3)5Cl]Cl2}$ is given to be 2.
[![enter image description here][1]][1]
In other textbooks and in the [question][2] here, we get the idea that:
>The primary valency of a compound is equal to its oxidation state.
In 'I... |
What is the chemical formula of ghee (Indian butter)? Also, name the elements present and state the number of their atoms. |
What is the chemical formula of ghee? |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.