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We were told in a first year introductory Thermodynamics and Kinetics lecture and also from wikipedia that there are 3 main assumptions for the derivations used in Transition State Theory, but I'm not sure how or why they have been assumed?
1) Reactants are in constant equilibrium with the transition state structu... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/JDlw0.jpg
Why C is considered as correct option even though lead sulphide forms black precipitate and lead sulphate forms white precipitate? Image is added of original Question to make question reliable.
JEE Advance 2016 |
We were told in a first year introductory Thermodynamics and Kinetics lecture, and also from Wikipedia, that there are 3 main assumptions for the derivations used in Transition State Theory, but I'm not sure how or why they have been assumed?
1. Reactants are in constant equilibrium with the transition state structu... |
What is the reasoning behind the assumptions of Transition State Theory? |
Question:
---------
> 28. The reagent(s) that can selectively precipitate $\ce{S^2-}$ from a mixture of $\ce{S^2-}$ and $\ce{SO4^2-}$ in aqueous solution is(are):
>
> (A) $\ce{CuCl2}$
>
> (B) $\ce{BaCl2}$
>
> (C) $\ce{Pb(OOCCH3)2}$
>
> (D) $\ce{Na2[Fe(CN)5NO]}$
Answer:
-------
>! **(A) or (A) and... |
Question:
---------
> 28. The reagent(s) that can selectively precipitate $\ce{S^2-}$ from a mixture of $\ce{S^2-}$ and $\ce{SO4^2-}$ in aqueous solution is(are):
>
> (A) $\ce{CuCl2}$
>
> (B) $\ce{BaCl2}$
>
> (C) $\ce{Pb(OOCCH3)2}$
>
> (D) $\ce{Na2[Fe(CN)5NO]}$
Answer:
-------
>! **(A) or (A) and... |
I had read about the two important methods used for the concentration of an ore - Roasting and Calcination. I have a doubt regarding why both the methods are carried out at temperatures not above the ore's melting point.
After some research, I have been able to conclude that one of the reasons is the formation of co... |
Why are calcination and roasting processes carried out at a temperature just below the ore's fusion temperature? |
Consider 1-indanone:
[![1-Indanone][1]][1]
I am supposed to find the rearrangement product on treating this with hydroxylamine (which gives an oxime) and then $\ce{H+}$ (with heat). I am aware of the mechanism of Beckmann Rearrangement, and also know that the migration of the group anti to the hydroxyl group p... |
What class of compounds does this belong to, if it exists; $$\ce{CH3-CH2-C\equiv N^{+}- CH3}$$
I honestly don't know if it exists; it popped up in my head while I was reading up on nitrile compounds, and I haven't heard of this type of molecule, thus the question.
If it doesn't exist, why not? |
**Birefrigence** is a result of structural anisotropy observed for crystals other than of the cubic Bravais class. Then, interaction of vectorial properties (e.g., light) with said material is anisotropic, too. It is a phenomenon seen both for inorganic, as well as organic materials (examples listed e.g., [here][1]). A... |
This question was asked in an exam.
The lowest energy electronic state for excited state carbon atom is
a.
1D2
b.
3D1
c.
3D3
d.
3D2
Although we have been taught Hund's rule for determmining the relative energies for various term symbols in the ground state, I haven't read anything abou... |
This question was asked in an exam:
>The lowest energy electronic state for excited state carbon atom is,
a. $^1D_2$
b. $^3D_1$
c. $^3D_3$
d. $^3D_2$
Although we have been taught Hund's rule for determining the relative energies for various term symbols in the ground state, I haven't read anything... |
> Estimate the ratio of $\ce{Tb^3+}$ to $\ce{Tb^4+}$ in $\ce{Tb_6O_11}$.
For my solution I knew that I had to get a sum of 22 positive charges from 6 $\ce{Tb^3+}$ and $\ce{Tb^4+}$ ions, so I just added different combinations until I found that $4(\ce{Tb^4+})+2(\ce{Tb^3+})$ gave me the desired value to have an overa... |
How to identify the ratio of oxidation states in terbium ions in its mixed oxide? |
Outside of bonds between metal atoms=metallic bonds, non-metals=covalent bonds (molecules), it is difficult for me to determine what kind of bond it is.
I know that in the rule metals and non-metals form ionic bonds and that the ionic part of such bonds increases with increasing electronegativity difference and that F... |
How to apply the Fajans' rules? |
For lighter elements, the shells fill in order. Starting at the transition metals, an outer s orbital *may* fill before an inner d orbital, so the electron configuration of *unioninzed* cobalt is written $\ce{[Ar]}4\mathrm s^1\,3\mathrm d^7$, rather than $\ce{[Ar]}3\mathrm d^7\,4\mathrm s^1$.
There is a [video][1] d... |
My undershirts have turned yellow in the armpit area without the benefit of aluminum antiperspirants. I assumed the stains were from carbonaceous exudants from my pores - or the biogenic products of bacterial life on my skin.
So I bleached the undershirts, soaked them in a diluted bleach (sodium hypochlorite) soluti... |
I was using NaOH to remove hardened grease from my stove burners, and it began to generate a lot of bubbles, some of which merged into a big bubble and erupted into the surface, but most formed a very thick foam.
I left it reacting for a few minutes and it started making way too much foam, about 3 liters of it.
... |
What determines the consistency of hydrogen foam when reacting NaOH + Al? |
I was using NaOH to remove hardened grease from my stove burners, and it began to generate a lot of bubbles, some of which merged into a big bubble and erupted into the surface, but most formed a very thick foam.
I left it reacting for a few minutes and it started making way too much foam, about 3 liters of it.
... |
I am tutoring my nephew for his science GCSEs; and his chemistry textbook states that you can tell how pure any compound is by how close its melting and boiling points are to the "official" mp and bp for that compound. It says that impurities will always lower the melting point of **any** compound, but - paradoxically ... |
A solution is cloudy at lower concentration and becomes clear at higher concentration. Why? |
Why is Aniline a poor substrate for Nitration reaction? |
I am an engineering student who loves physics but didn't quite enjoy chemistry.
**a.** When I was in high school chemistry to me was something not as inspiring as physics but in which I couldn't solve problems well. Things looked no more than the arithmetics, but I got the answers wrong.
**b.** Reading university... |
I have that $100$ mM of K$_3$Fe(CN)$_6$ is dissolved in equimolar of the organic ion (which I assume is HCN). In the solution Fe(CN)$_6$$^{3-}$ reacts to form Fe(CN)$_6$$^{4-}$.
The formation of Fe(CN)$_6$$^{4-}$ as a function of time is measured in a Na$_2$SO$_4$ (which does not take part in the reaction) solution... |
I was using $\ce{NaOH}$ solution to remove hardened grease from my stove burners, and it began to generate a lot of bubbles, some of which merged into a big bubble and erupted into the surface, but most formed a very thick foam.
I left it reacting for a few minutes and it started making way too much foam, about 3 li... |
What determines the consistency of hydrogen foam when reacting aluminium with sodium hydroxide solution? |
During S<sub>N</sub>2 reaction with a silicon compound, a pentacovalent intermediate is formed, while there is no such intermediate formed with carbon compounds (only a pentacovalent transition state). Why is it so? I need an MO explanation (no d orbitals involved). |
I don't understand this statement written in my textbook about the polarising power of cations:
>If two cations have the same size and charge, then the one with *pseudo noble gas configuration* ( with 18 electrons in the outermost shell) has greater polarising power than the other with *noble gas configuration* (wi... |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/1wSRO.png
I am supposed to perform the shown reaction in the lab soon, but I don't really understand the mechanism behind it. I got told by my lab assistent that the is the mechanism is an electrophilic aromatic substitution in which the... |
Why do Resorcinol and Iodine react to 2-Iodobenzen-1,3-diol? |
Basically My question is, can chemistry predict the future? because the logic would tell me that the most stable alkene (2) which is most substituted would react the slowest, but on the other hand it would form the most stable carbocation (tertiary) which would mean it's best for this specific reaction which would make... |
Which Alkene Would react faster with HCl? |
I am having difficulty normalizing the wavefunction for a free particle in 1 dimension.
I have sent an attachment of my working out.
Could someone please let me know of my mistake?
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/ajLVn.png
Thank you.
|
I am having difficulty normalizing the wavefunction for a free particle in 1 dimension.
I have sent an attachment of my working out.
### My attempt at the normalisation
Free electron:
$$-\frac{\hbar^2}{2m}\frac{\mathrm d^2 \psi(x)}{\mathrm dx^2} = E\,\psi(x)$$
\begin{align}
\psi(x) &= A\sin(kx) + B\cos(kx... |
Your attempt has multiple issues, most of which are very basic.
The first issue that I noticed was how you expanded and simplified your integral.
> \begin{align}
\int^\infty_{-\infty}[A^2\sin^2(kx) &+ AB\sin(kx)\cos(kx) \\
&+ AB\cos(kx)\sin(kx) +B^2\cos^2(kx)]\mathrm dx = 1 \tag{1}
\end{align}
>
>Since, $\... |
I'm about to teach concrete to some high school children. I'm not a chemist but as I understand it the limestone cycle is this:
$\ce{CaCO3 -> CaO + CO2}$
$\ce{CaO + H2O -> Ca(OH)2}$
$\ce{Ca(OH)2 + CO2 -> CaCO3 + H2O}$
Two questions:
1) The water has to go somewhere or the concrete will stay wet.... |
I'm about to teach concrete to some high school children. I'm not a chemist but as I understand it the limestone cycle is this:
$$
\begin{align}
\ce{CaCO3 &-> CaO + CO2}\tag{R1}\\
\ce{CaO + H2O &-> Ca(OH)2}\tag{R2}\\
\ce{Ca(OH)2 + CO2 &-> CaCO3 + H2O}\tag{R3}
\end{align}
$$
Two questions:
1) The water... |
> Which alkene reacts faster with HCl?
>
> [![1: methylidenecyclohexane; 2: 1-methylcyclohex-1-ene; 3: 3-methylcyclohex-1-ene; 4: 4-methylcyclohex-1-ene; 5: ethenylcyclohexane][1]][1]
The logic tells me the most stable alkene **2** which is the most substituted would react the slowest.
On the other hand, it wou... |
Which alkene reacts faster with HCl? |
Theoretically electrolysis of water yields Hydrogen and Oxygen in gaseous form.
But to enhance conductivity we have to add an electrolyte like NaOH or KOH.
Does this produce any other gases along with Oxygen?? Does Na or OH ions also come out as some form of gas?
Or practically speaking can people breathe the ... |
What are the gaseous of outputs of electrolysis of Water along with a electrolyte? |
I am trying to estimate the volume of oxygen that will be produced by electrolysis of water at normal temperature and pressure with a current of 50 Amps. The following is my calculation.
The reaction is
$$
2H_2O \rightarrow O_2 + 4H^+ + 4e^-
$$
Therefore, to produce 1 mole of $O_2$ (24 liters), we need to move ... |
I'm learning organic chemistry from Clayden's book (2e). I've noticed they draw the cyclic hexenone below like this:
[![enter image description here][1]][1]
[![enter image description here][2]][2]
However, since the carbon on the carbonyl group is sp2 hybridized I am wondering if this is correct. Shouldn't this... |
Is the cyclic hexenone drawn correctly in this depiction? |
Theoretically electrolysis of water yields Hydrogen and Oxygen in gaseous form.
But to enhance conductivity we have to add an electrolyte like NaOH or KOH.
Does this produce any other gases along with Oxygen? Does Na or OH ions also come out as some form of gas?
Or practically speaking can people breathe the Oxy... |
What are the gaseous outputs of electrolysis of Water along with NaOH or KOH? |
I regularly home-distil small amounts of potable alcohol (ethanol), mainly from fermented sugar(s) solutions (the 'wash').
My still is a box standard, $4.5\mathrm{L}$ electrically heated (safety!), air-cooled pot still, which produces exactly $1$ single stage distillation ('one Theoretical Plate') Starting from a wa... |
Okay so let me start from the beginning.
I know that ΔH= ΔU + p ΔV ( at constant pressure).
Expanding ΔU,
ΔH= q + pΔV + pΔV ( q at constant pressure) -(1)
Next my chemistry book continued to say that in expansion work done by gas is negative, so the pv work terms cancel out, i.e,
ΔH= q - p ΔV + p ΔV
... |
I regularly home-distil small amounts of potable alcohol (ethanol), mainly from fermented sugar(s) solutions (the 'wash').
My still is a box standard, $4.5\mathrm{L}$ electrically heated (safety!), air-cooled pot still, which produces exactly $1$ single stage distillation ('one Theoretical Plate') Starting from a wa... |
I regularly home-distil small amounts of potable alcohol (ethanol), mainly from fermented sugar(s) solutions (the 'wash').
My still is a box standard, $4.5\mathrm{L}$ electrically heated (safety!), air-cooled pot still, which produces exactly $1$ single stage distillation ('one Theoretical Plate') Starting from a wa... |
In one task/example there is gas phase reaction and it is said that reaction takes place at pressure of 1 bar and standard Gibbs energy of reaction is needed to be calculated. In this task 1 bar is meant to be equilibrium pressure of a mixture. Problem I have is that total pressure initially is less than 1 bar since nu... |
Reading this question, I realized that OP is very new to organic chemistry, and in need for learning a lot about electrophilic aromatic substitution reactions. Thus, I recommend that OP should concentrate on the electrophilic aromatic substitution reactions and read the chapters of OP's textbook dedicated to that subje... |
[![Iodination Reaction][1]][1]
[1]: https://i.stack.imgur.com/1wSRO.png
I am supposed to perform the above shown reaction in the lab soon, but I don't really understand the mechanism behind it. I got told by my lab assistant that the mechanism is an electrophilic aromatic substitution in which resorcinol (b... |
Why do resorcinol and iodine react to give 2-iodobenzen-1,3-diol? |
I am trying to estimate the volume of oxygen that will be produced by electrolysis of water at normal temperature and pressure with a current of $\pu{50 A}$. The following is my calculation:
The reaction is
$$\ce{2H2O -> O2 + 4H+ + 4e-}$$
Therefore, to produce $\pu{1 mol}$ of $\ce{O2}$ ($\pu{24 L}$), we need to... |
At very dilute concentrations, the solvating power of water overcomes the natural tendency of surfactant molecules to agglomerate into a separate phase. The shear numerical excess of water molecules just about totally dissociates the bulk surfactant and dissolves it as separate molecules. So a mixture of surfactant and... |
Mechanism of Fischer esterification: Does the carboxylic acid gives off OH- or H+? |
The comments on [this][1] question seem to detail a trend in which $\ce{NR3+, NHR2+, NH2R+}$ all show meta-directing nature towards electrophilic substitutio, with the slightly stronger para-direction of $\ce{NH3+}$ being the odd one out, as cited from March's Advanced Organic Chemistry.
The 2020 edition has this to... |
The comments on [this][1] answer seem to detail a trend in which $\ce{NR3+, NHR2+, NH2R+}$ all show meta-directing nature towards electrophilic substitutio, with the slightly stronger para-direction of $\ce{NH3+}$ being the odd one out, as cited from March's Advanced Organic Chemistry.
The 2020 edition has this to s... |
The comments on [this][1] answer seem to detail a trend in which $\ce{NR3+, NHR2+, NH2R+}$ all show meta-directing nature towards electrophilic substitution, with the slightly stronger para-direction of $\ce{NH3+}$ being the odd one out, as cited from March's Advanced Organic Chemistry.
The 2020 edition has this to ... |
I am working through a paper, [Lateral flow immunochromatographic assay on a single piece of paper][1]. I'm having trouble understanding one of the points!
Under the **Device fabrication** question, it says:
> The sample and conjugate release regions were treated with a blocking solution to prevent nonspecific bi... |
Okay so let me start from the beginning.
I know that ΔH= ΔU + p ΔV ( at constant pressure).
Expanding ΔU,
ΔH= q + pΔV + pΔV ( q at constant pressure) -(1)
Next my chemistry book continued to say that in expansion work done by gas is negative, so the pv work terms cancel out, i.e,
ΔH= q - p ΔV + p ΔV
... |
I was required to find the products on heating the hydroxide of; [![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/ew6qv.jpg
Now it's easy enough to find the answer; Hoffman elimination isn't going to happen from the methyl, and the n-propyl doesn't have $\beta$-hydrogens as acidic as tha... |
Initially, we are given a solution containing two salts, they can be either carbonate or chloride salts (we do not know their composition initially).
Generally, $\ce{AgNO3}$ is used as a confirmatory test of $\ce{Cl-}$ (a white precipitate is obtained on adding silver nitrate to solution containing the chloride salt... |
@user1055 answered the question pretty much. I am just going to add a complementary answer which has the abstract to the paper which @user1055 mentioned. The abstract of the paper mentions the various products of the decomposition reaction:
> The thermal decomposition behavior of terephthalic acid (TA) was
> invest... |
Theoretically electrolysis of water yields Hydrogen and Oxygen in gaseous form.
But to enhance conductivity we have to add an electrolyte like $\ce{NaOH}$ or $\ce{KOH}$.
Does this produce any other gases along with Oxygen? Does $\ce{Na+}$ or $\ce{OH^-}$ ions also come out as some form of gas? Or practically speakin... |
Okay so let me start from the beginning.
I know that $ΔH= ΔU + p ΔV$ ( at constant pressure).
Expanding $ΔU$,
$$ΔH= q + pΔV + pΔV ~~~~~\text{(q at constant pressure)} \tag{1}$$
Next my chemistry book continued to say that in expansion work done by gas is negative, so the PV work terms cancel out, i.e,
... |
Your book uses the "chemistry sign convention", that is, $w=-p_\textrm{ex} \Delta V$, where $p_\textrm{ex}$ is the external pressure.
However the enthalpy is not defined in terms of the external pressure but rather the pressure $p$ in the system: $H=U+pV$. From the definition of enthalpy it follows that $\Delta H... |
I have to do an experiment where I will find out what the influence of the concentration on the rate of a homogenous reaction is.
We are asked to create 2 solutions, respectively A and B:
$$\ce{KI + Na2S2O3 + Starch + water}$$
and
$$\ce{H2O2 + H2SO4 + water}$$
As long as A and B aren't added together... |
There are 4 different timescales in material characterization (as classified in the Atkins textbook):
a. Time during which a quantum of radiation or a particle can interact with a molecule.
b. Lifetime of excited state of a molecule.
c. Minimum lifetime species must have to be seen as a distinct species.
d.... |
There are 4 different timescales in material characterization (as classified in the Atkins textbook):
a. Time during which a quantum of radiation or a particle can interact with a molecule.
b. Lifetime of excited state of a molecule.
c. Minimum lifetime species must have to be seen as a distinct species.
d.... |
We're learning about chromatography in class, and I'm confused about all the different types (e.g. those that separate liquid-liquid solutions vs. those that separate liquid-solid solutions vs. those that separate solid-solid solutions, etc.).
Could you provide a summary of the similarities between all forms of chro... |
Textbook Question:
> The rhodopsin molecules in the retina contain a derivative of vitamin A called cis-retinal (Figure 6). On exposure to light, cis-retinal becomes an isomer called trans-retinal.
>
> [![enter image description here][1]][1]
>This process helps cause an electrical impulse to be transferred to the... |
This is a question that had me puzzled for quite a while. I feel that information is missing.
A weak acid, $\ce{HA}$, $K_\textrm{a} = \pu{1.0e-4 M}$, is titrated with $\ce{NaOH}$. The concentration of $\ce{NaA}$ at the equivalence point is $\pu{0.010 M}$. What is the pH at the equivalence point?
a) 4.0
b) 6... |
I found a question
>Which is more stable among the following?
>
>(a) $\ce{CaCO3}$
>
>(b) $\ce{MgCO3}$
Answer : (a)
Explanation was given as:
>$\ce{Mg^2+}$ has smaller radius than $\ce{Ca^2+}$ and thus charge/radius of $\ce{Mg^2+}$ is greater , hence it is less stable.
While when reading about the coo... |
I have to do a lab about enzyme catalysis with peroxidase in my chemistry class. We are to use the blank control solution in the experiment. My question is, why can we not use water instead? I did some research about this and someone says something like "It is because the water blank absorbs so much light that the usab... |
I know that when $\ce{Cu^{2+}}$ ions react to $\ce{Fe}$ atoms, it becomes $\ce{Cu}$ + $\ce{Fe^{2+}}$. My question is, why?
Copper atoms normally have 29 electrons. This means that in the K-shell there are 2 electrons, in $L = 8$ electrons, in $M = 18$ electrons and in $N = 1$ electron. (Yes I know that there is a sy... |
I observed a doublet with peaks at 5.6336 and 5.5886 ppm with the NMR instrument running at 300 MHz, and got a $J_\ce{PH}= \pu{13.5 Hz}$. Is this correct for this molecule (ethoxycarbonylmethyl(triphenyl)phosphonium bromide)? This value is larger than the hydrogen coupling constants for the C-C bonds. Is this larger co... |
Can ketones next to a nitrogen hetero atom tautomerise? |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/d5nYp.jpg
The answer given is (D) but I think (B) should be the answer as the concerned benzylic carbon in option (D) is an unstable tetrahedral complex and it should break. Besides, the medium is acidic so it should catalyse this process... |
Why lactols being tetrahedral complexes do not break? |
>$\ce{R-OH + NaBr + H2SO4->R-Br + NaHSO4 + H2O}$
---
Due to sulphuric acid, the ${\ce-OH}$ group will convert into $\ce{-H2O+}$ which is a great leaving group so I thought it would form a carbocation and then the $\ce{Br-}$ would attack to form the alkyl bromide. That is, it would follow $S_N1$ path but I al... |
While reading an organic chemistry textbook I saw the following Formula for calculating equilibrium constant of an acid-base reaction
Consider following acid base reaction in which $\ce{HA}$(reactant acid) and $\ce{HB+}$(product acid) are acids in forward and backward reaction respectively.
$$\ce{HA + B <=> A- +... |
The issue as I can see it here is a simple misunderstanding that can rectified:
$K_\mathrm a$ is a constant even if $\ce{[A]}$ is not. (which is how it was defined)
The definition of $k_\mathrm a$ is as follows:
> $K_\mathrm a$ , the acid ionization constant, is the equilibrium constant for chemical reactions ... |
While reading an organic chemistry textbook I saw the following Formula for calculating equilibrium constant of an acid-base reaction
Consider following acid base reaction in which $\ce{HA}$(reactant acid) and $\ce{HB+}$(product acid) are acids in forward and backward reaction respectively.
$$\ce{HA + B <=> A- +... |
I came across a question :
Which of the following compound does not decolourise an acidified solution of KMnO4?
Answer was FeCl3.
After doing a bit of research I found that KMnO4 oxidises HCl to Cl2.
I doubt whether KMno4 would also oxidise Chloride ions in case of acidified solution of FeCl3.
(I know iron cannot ... |
Will KMnO4 react with FeCl3? |
I know that plastic susceptible to UV attack will create free radicals when put under sunlight even short time. I'd like to know if the photodamage will stop at all once it is taken away from the sunlight or if it will still do photodamage to the plastic but the rate becomes very slow because of the absence of light bu... |
When reading about $\ce{SeO_2}$ I read this following reaction:
$\ce{CH3CH2COCH3 ->[SeO2] CH3CH2COCHO + CH3COCOCH3}$
In the following reaction it was stated that $\ce{CH3CH2COCHO}$ was the major product. But I fail to understand why ?<br>
The two possible reasonings I can think of are that the terminal hydrogen ... |
I came across a question :
>Which of the following compound does not decolourise an acidified solution of $\ce{KMnO4}$?
Answer was:
>! $\ce{FeCl3}$
After doing a bit of research I found that $\ce{KMnO4}$ oxidises $\ce{HCl}$ to $\ce{Cl2}$.
I doubt whether $\ce{KMnO4}$ would also oxidise chloride ions in case ... |
Will potassium permanganate react with ferric chloride? |
[![enter image description here][1]][1]
[1]: https://i.stack.imgur.com/d5nYp.jpg
The answer given is (D) but I think (B) should be the answer as the concerned benzylic carbon in option (D) is an unstable tetrahedral complex and it should break. Besides, the medium is acidic so it should catalyse this process... |
From my understanding, battery provides a driving force to pull electrons from anode, this the anode become positively charged.
Suppose the anode is copper, the process should be like this:
$\ce{Cu->Cu^2+ +2e-}$
However, the copper ions should be dissolved into the electrolyte after this process, and only neut... |
Why would electrode be positively charged in electrolysis? |
I'm working on a website where I want to provide the pH level of plants! Although i don't even know what this is (i have zero knowledge in chemistry) I have to provide it! What I want to do is provide the pH spectrum on the website so that it would point to the correct pH level of a specific plant. Let's use the follow... |
This is the exact question I faced on an exam:
>Calculate the $\mathrm{pH}$ of $\pu{0.05 M}~\ce{Na2CO3}. \\(\ce{H2CO3}: K_\mathrm{a_1}= 4\times 10^{-7},~ K_\mathrm{a_2}= 4.7\times 10^{-11})$
### Solution ###
$$\ce{Na2CO3 ->2Na+ + CO3^2-}$$
I suppose nothing that can contribute to the $\mathrm{pH}$ of a solu... |
This is a question that had me puzzled for quite a while. I feel that information is missing.
>A weak acid, $\ce{HA}$, $K_\textrm{a} = \pu{1.0e-4 M}$, is titrated with $\ce{NaOH}$. The concentration of $\ce{NaA}$ at the equivalence point is $\pu{0.010 M}$. What is the pH at the equivalence point?
a) 4.0
b) ... |
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