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Why is the deposition of silver more uniform from [Ag(Cl)₂]⁻ (aq) than from Ag⁺? |
I have seen videos and discussions about alcohol cracking acrylic, and waterblock manufacturers reminding users to not use alcohol in cooling system with plexiglass acrylic, but why is it so?
That question only asked for the effect, but here I already know the effect, I am asking for the reason for the effect, which... |
I have a question about fats. This may sound cliché! Because we are in the era of "trans-fat" free, "unsaturated" food. Not to mention it's the period *where people get sicker and die faster (oh may be, the statistics weren't obvious in the past...)*.
Fats are important part of our diet and major source of energy (... |
Why does alcohol crack acrylic (plexiglass)? |
I have seen videos and discussions about alcohol cracking acrylic, and waterblock manufacturers reminding users to not use alcohol in cooling system with plexiglass acrylic, but why is it so?
That question only asked for the effect, but here I already know the effect, I am asking for the reason for the effect, which... |
can you check this please ? @KlausWarzecha
in a 20% solution of $\ce{CuSO4}$ we have 20 g of Cu and 80 g of H2O
then
in every 259.6 $\ce{CuSO4*5H2O}$ we have 159.6 $\ce{CuSO4}$
so for every X $\ce{CuSO4*5H2O}$ we have 20 g $\ce{CuSO4}$
x=31.87 g
is this correct ? |
The uniformity of a deposition depends on more parameters, but in this case the difference is in electromigration effect. $\ce{Ag+}$ ions are atrracted to the electrode surface, but the complex $\ce{[Ag(Cl)2]-}$ is repulsed. Cyanides form complexes as well: $\ce{[Ag(CN)2]-}$ or $\ce{[Ag(Cl)3]2-}$ and they are also re... |
In the book that I'm reading it is mentioned higher molar mass results in stronger van der waals force, but didn't continued why.
I wonder why is that so? molar mass is actually dependable on the number of protons and neutrons, how can it be effective on the wan der waals force? |
How do I balance this using the half-reaction method: \begin{align*} Zn(s) + HCl(aq) \rightarrow Zn^{2+} (aq) + H_2 (g) \end{align*}
I would first split it up in its ionic components:
$Zn(s) + H^+ + Cl^- \rightarrow Zn^{2+} (aq) + H_2 (g)$.
Then we have first the oxidation-reaction: $Zn(s) \rightarrow Zn^{2+} (... |
The uniformity of a deposition depends on more parameters, but in this case the difference is in electromigration effect. $\ce{Ag+}$ ions are atrracted to the electrode surface, but the complex $\ce{[Ag(Cl)2]-}$ is repulsed. Cyanides form complexes as well: $\ce{[Ag(CN)2]-}$ or $\ce{[Ag(Cl)3]2-}$ and they are also re... |
Which all elements of Group 15 of the periodic table have allotropes?
P, As and Sb have well-known allotropes.
P - White, Red and Black.
As - Yellow, Black and Gray(Grey)
Sb - White, Yellow and Black
([Source][1])
**What about Nitrogen and Bismuth?**
* The same [source][2] ... |
So I came across this diagram,the other day:![diffrent types of bonds][1]
[1]: https://i.stack.imgur.com/Zzxk4.jpg
As a chemistry student ,I am well-versed with the dashed and wedged lines but I was wondering what the wavy and the dotted line represent? |
> I was wondering what the wavy and the dotted line represent?
- A **dashed** line indicates that the bond is extending **behind the plane** of the drawing surface
- A **bold-wedged** line indicates that the bond is **protruding out** from the plane of the drawing surface
- A **solid** line indicates that the b... |
Can all lattices be described as one of the fourteen Bravais lattices?
Is the hexagonal close packed structure also one of the fourteen Bravais lattices? |
Are all lattices Bravais lattices? |
According to the Wikipedia page about [rust][1], there are red and green types of rust that occur on iron. Red rust is the reaction with oxygen and water and the green with chlorine (in oxygen poor environments).
I understand the chemical reactions that forms these types of rust, but in the Wikipedia article, it st... |
According to the Wikipedia page about [rust][1], there are red and green types of rust that occur on iron. Red rust is the reaction with oxygen and water and the green with chlorine (in oxygen poor environments).
I understand the chemical reactions that forms these types of rust, but in the Wikipedia article, it st... |
What are the meanings of dotted lines and waves in structural formulas? |
I drew a rough picture of the two cells, and marked each position with a distinct letter:![enter image description here][1]
The whole reason I am asking this question is that I am bit confused and unsure about some of the chemistry and physics concepts. It will be extremely helpful if you guys can tell me if what I di... |
Are rate constants for water exchange of transition metal aqua-complexes tabulated anywhere ? I haven't been able to find a resource which is anywhere near comprehensive. |
I understand that $\ce{CdCl2}$ has a rhombohedral unit cell as shown in [this book.][1] However I often find it being referred to as a "CCP analogue" of $\ce{CdI2}$. Presumably it is the chlorides which form a cubic lattice; how would you draw the cubic unit cell ?
[1]: https://books.google.co.uk/books?id=-EKCm5... |
> I was wondering what the wavy and the dotted line represent?
- A **dashed** line indicates that the bond is extending **behind the plane** of the drawing surface
- A **bold-wedged** line indicates that the bond is **protruding out** from the plane of the drawing surface
- A **solid** line indicates that the b... |
a) 3.8
b) 7
c) 9
d) 12
**My Attempt:**
Cs+ + H2O --> CsOH + H+ (becase CsOH is a strong base, the forward reaction should not occur right?
Br- + H2o --> HBr + OH- (because HBr acid, the forward reaction should also no occur right?)
Any help would be greatly appreciated!!
|
What is the pH of CsBr? |
a) 3.8
b) 7
c) 9
d) 12
**My Attempt:**
$\ce{Cs+ + H2O <<=> CsOH + H+}$ (because $\ce{CsOH}$ is a strong base, the forward reaction should not occur right)?
$\ce{Br- + H2O <<=> HBr + OH-}$ (because $\ce{HBr}$ acid, the forward reaction should also no occur right?)
Any help would be greatly appreciated!!... |
Would copper wires from power transmission or telephone lines acquire a patina but remain largely intact, or oxidize into dust after a century or more without replacement or maintenance?
Obviously environmental factors would be enormous; ideally I'd like to know what the metal's state would be in ideal (underground?... |
To what state would copper wiring revert if abandoned for centuries? |
Is time a measurement of entropy? Is it because time is increasing forever? |
Is time a measurement of Entropy? |
Is time a measurement of entropy? Is it because time is increasing forever?
Well after reading about the Second Law of Thermodynamics and working with Entropy, I began to realize that if time can be interpreted as a measure of Entropy, since it is always increasing.
> Since almost everything decays with time, I t... |
My textbook reads as follows:
> "When a gas is adsorbed, the freedom of movement of its molecules become restricted. This amounts to decrease in the entropy of the gas after adsorption, i.e. Entropy change is negative."
But now, I am unable to understand why it isn't a violation of the 2nd Law of Thermodynamics w... |
Does adsorption violate thermodynamics? |
I am interested in ab initio computational chemistry.I am trying to figure out what I should study. I know that I should study physical chemistry, mathematics, and programming. However, I am not sure in what I should be focusing on. It is a "recent" field. And books on the topic are rather specific. Can anyone working ... |
Computational Chemistry (Ab Initio), what should I study? |
How do I balance this using the half-reaction method: $$\ce{Zn(s) + HCl(aq) -> Zn^{2+} (aq) + H_2 (g)}$$
I would first split it up in its ionic components:
$\ce{Zn(s) + H^+ + Cl^- -> Zn^{2+} (aq) + H_2 (g)}$.
Then we have first the oxidation-reaction: $\ce{Zn(s) -> Zn^{2+} (aq)}$. Balancing this with electrons ... |
I sprinkled salt on my turkey skin and left it to dry out over night. It was covered with aluminum foil. The next morning the aluminum foil had holes ‘burnt’ in it and the turkey skin turned silver at the spots where the salt crystals had touched the aluminum foil. Was my turkey poisoned with aluminum at this point? I ... |
Why did the salt on the skin of my turkey react with the aluminum foil it was touching? |
Could someone, please, explain to me how the Standard Hydrogen Electrode works and how it is used to measure electrode potentials? Also, why does it have a potential value of zero? |
<h3>In case of metal deficient defects in the crystal lattice of a metal, the positive void are filled by electrons. <p></h3>
- How does this result in the coloration of a substance?
- Does this condition arise only in the case of metals?
|
How does zinc become oxidized when it's not in direct contact with copper ions in a galvanic cell? |
Is it possible to reduce raspberry ketone, which is 2-(4-hydroxyphenyl)ethyl methyl ketone, to ethyl methyl ketone? How would I do it in practice? |
Is it possible to reduce raspberry ketone (*4-(4-Hydroxyphenyl)butan-2-one*) to ethyl methyl ketone? How would I do this in practice? |
What is an effective extraction solvent for removing hydrocarbons from soil (using a a soxhlet extractor)? |
So in order to solve this, apparently all you need to do is plug it into the equation
pH = log [H3O+]
where the concentration of H3O+ is 5M. But why can we assume this? Don't we need to create an ice table from HCl + H2O--> H3O+ + Cl- and use the Ka value of HCl to solve this?
Thank you!! |
What is the pH of a 5M solution of HCl? |
So in order to solve this, apparently all you need to do is plug it into the equation
pH = -log [H3O+]
where the concentration of H3O+ is 5M. But why can we assume this? Don't we need to create an ice table from HCl + H2O--> H3O+ + Cl- and use the Ka value of HCl to solve this?
Thank you!! |
So in order to solve this, apparently all you need to do is plug it into the equation
$\ce{pH = -log [H3O+]}$
where the concentration of $\ce{H3O+}$ is 5M. But why can we assume this? Don't we need to create an ice table from $\ce{HCl + H2O-> H3O+ + Cl-}$ and use the K<sub>a</sub> value of $\ce{HCl}$ to solve t... |
What is an effective extraction solvent for removing hydrocarbons from soil (using a soxhlet extractor)? |
So in order to solve this, apparently all you need to do is plug it into the equation
$$\mathrm{pH} = -\log[\ce{H3O+}]$$
where the concentration of $\ce{H3O+}$ is 5M. But why can we assume this? Don’t we need to create an ice table from $\ce{HCl + H2O-> H3O+ + Cl-}$ and use the $K_\text{a}$ value of $\ce{HCl}$ ... |
I use borax to clean everything. the other day I thought it would be a good idea to mix a little borax with my shampoo while showering. after lathering it on my scalp about 30 seconds it began to give off a really bad chemical smell, almost like a perm solution. what was the borax reacting with the product in my hair ... |
I understand this is a simple question (I'm in high school), but for some reason the numbers just are not working for me.
Given:
$$\Delta H°_{comb} = -1301kJ for\ \ce{C2H2(g)}$$
$$\Delta H°_f = -394 kJ for\ \ce{CO2(g)}$$
$$\Delta H°_f = -242 kJ for\ \ce{H2O(g)}$$
Calculate $\Delta H_f$ for $C_2H_{2(g)}$.
M... |
I was trying to compare acidity of some organic compounds but can't understand some:
Why should 2,6-Dimethyl-4-nitrophenol be more acidic than 3,5-Dimethyl-4-nitrophenol?
I have been trying to figure it out using various factors like hyperconjugation and induction effect of Me group but its not working.Help! |
I was trying to compare acidity of some organic compounds but can't understand some:
Why should 2,6-Dimethyl-4-nitrophenol be more acidic than 3,5-Dimethyl-4-nitrophenol?
I have been trying to figure it out using various factors like hyperconjugation and induction effect of Me group but its not working.Suppose i take... |
A solution is created by mixing 250 mL of 1M HCl, 250 mL of CH3COOH and 500 mL of 1.5 M CsOH
The Ka(CH3COOH) = 1.8 x 10^-5
What is the pH of this solution?
I am stuck between HCl and CsOH since they are both a strong acid and base (respectively) meaning that they should both have a substantial affect on the pH... |
After mixing, which species has the dominant affect on the pH of the solution that remains? |
I'm not sure if I'm missing your question, but I thought that perhaps you could use the relation
$\ce{pH=pKa}$ at the half equivalence point? The answer would be still incorrect but closer?
Otherwise, you could probably use stoichiometry to solve for Ka at the beginning or the end of the titration by constructing ... |
For example, which is the right way to name this certain compound:
2-bromo-4-methylene-hexane
or
4-bromo-2-ethylpent-1-ene?
Does the larger number of carbon in a chain take priority, like in the former, or does the carbon-carbon double bond take priority, like in the latter? |
How do you name an alkene using IUPAC rules if the longest carbon chain in this alkene does not include the double bond? |
Why is arsenic more chemically similar to phosphorus than is nitrogen (to phosphorus)?
I thought that it may be because both phosphorus and arsenic have d orbitals (albeit one has one that is filled and the other has an unfilled one).
Another possibility I thought was that because nitrogen held the electrons very... |
Why is arsenic more chemically similar to phosphorus than is nitrogen? |
I was trying to compare acidity of some organic compounds but can't understand some:
Why should 2,6-dimethyl-4-nitrophenol be more acidic than 3,5-dimethyl-4-nitrophenol?
I have been trying to figure it out using various factors like hyperconjugation and induction effect of Me group but its not working. Suppose i... |
A solution is created by mixing 250 mL of 1M HCl, 250 mL of 1 M CH3COOH and 500 mL of 1.5 M CsOH
The Ka(CH3COOH) = 1.8 x 10^-5
What is the pH of this solution?
I am stuck between HCl and CsOH since they are both a strong acid and base (respectively) meaning that they should both have a substantial affect on the ... |
A solution is created by mixing 250 mL of 1M $\ce{HCl}$, 250 mL of 1 M $\ce{CH3COOH}$ and 500 mL of 1.5 M $\ce{CsOH}$.
The $\ce{K_{a}(CH3COOH)}$ = 1.8 x 10<sup>-5</sup>
What is the pH of this solution?
I am stuck between $\ce{HCl}$ and $\ce{CsOH}$ since they are both a strong acid and base (respectively) meani... |
A solution is created by mixing 250 mL of 1M $\ce{HCl}$, 250 mL of 1 M $\ce{CH3COOH}$ and 500 mL of 1.5 M $\ce{CsOH}$.
The $\ce{K_{a}(CH3COOH)} = \mathrm{1.8 x 10^{-5}}$
What is the pH of this solution?
I am stuck between $\ce{HCl}$ and $\ce{CsOH}$ since they are both a strong acid and base (respectively) mean... |
Why might the O—H stretch in the IR of MY triphenylmethanol product be less intense than expected when compared to the expected IR for triphenylmethanol?
I'm interpreting the IR I took of my product, triphenylmethanol, to the expected IR I obtained from SDBS.
My IR: ![my triphenylmethanol product][1]
SDBS: !... |
Why might the O—H stretch in the IR of MY triphenylmethanol product be less intense than expected? |
I am designing a battery box to house lithium ion batteries in an electric vehicle. These batteries use an electrolyte which probably contains carbonate esters (eg. ethylene carbonate, dimethyl carbonate, diethyl carbonate).
If I use polycarbonate as the battery box material, should I be worried about an interaction... |
Very short question but maybe not a short answer ! As the probability of presence of electrons in a specific spatial position is defined as square of the wave function, I am wondering if there is a technique for molecular volume calculation based on the wavefunction.
Is there such a technique?
Update: I could ru... |
Wikipedia says :
> The term gram-atom (abbreviated gat.) has been used for a related but distinct concept, namely a quantity of a substance that contains Avogadro's number of atoms, whether isolated or combined in molecules. Thus, for example, 1 mole of MgB2 is 1 gram-molecule of MgB2 but 3 gram-atoms of MgB2.
Can a... |
What exactly does Gram atoms means? |
For instance, copper can form $\ce{[Cu(H2O)6]2+}$ so it accepts 6 electron pairs from $\ce{H2O}$ molecules to form dative covalent bonds. However it has one electron in the 4s subshell and 10 in the 3d subshell. To which shell does it accept these electrons? Is it to the 4d subshell? And how are these accepted electron... |
For instance, copper can form $\ce{[Cu(H2O)6]^2+}$ so it accepts 6 electron pairs from $\ce{H2O}$ molecules to form dative covalent bonds. However it has one electron in the 4s subshell and 10 in the 3d subshell. To which shell does it accept these electrons? Is it to the 4d subshell? And how are these accepted electro... |
$\ce{HNO3}$ always reduces its anion to give n=containing compounds 9 $\ce{NO2}$, $\ce{NO}$, and even $\ce(N2O}$ when reacting with metals, but with $\ce{Mg}$ and $\ce{Mn}$ it releases $\ce{H2}$. Is there a specific reason for this variation? |
$\ce{HNO3}$ always reduces its anion to give nitrogen containing compounds ( $\ce{NO2}$, $\ce{NO}$, and even $\ce{N2O}$) when reacting with metals, but with $\ce{Mg}$ and $\ce{Mn}$ it releases $\ce{H2}$. Is there a specific reason for this variation? |
cesium has a larger size and the effective nuclear charge that the valence electron experiences will be far less compared to that of lithium's, right?... but lithium is still considered the strongest reducing agent among all the alkali metals. why so? |
why is cesium not the strongest reducing agent instead of lithium? |
For example, which is the right way to name [this][1] certain compound:
2-bromo-4-methylene-hexane
or
4-bromo-2-ethylpent-1-ene?
Does the larger number of carbon in a chain take priority, like in the former, or does the carbon-carbon double bond take priority, like in the latter?
[1]: http://www.ch... |
I understand conformation to be any spacial arrangement of atoms that can be achieved through rotation of a single bond. I understand configuration to be the disposition of atoms/groups in space. However, would a conformational isomer also be a configurational isomer since the groups are arranged differently in space? ... |
A $20.0$-L nickel container was charged with $0.500$ atm of xenon gas and $1.50$ atm of fluorine gas at $400$ $^{\circ}$C. The xenon and fluorine react to form xenon tetrafluoride. What mass of xenon tetrafluoride can be produced assuming $100$ % yield?
**Attempt at solution:** From the description, the reaction can... |
Gas Stochiometry - where is my mistake in dealing with this problem? |
Gas Stoichiometry - where is my mistake in dealing with this problem? |
I'll be having a national test tomorrow. I'd like to clarify so that I don't answered it wrong. Which of this following have higher boiling points? Alkanes, Alkenes, or Alkynes, and why? Thank you for answering. |
I'll be having a national test tomorrow. I'd like to clarify so that I don't answered it wrong. Here's the question. **Which of this following have higher boiling points? Alkanes, Alkenes, or Alkynes, and why?** Thank you for answering. |
I'm wondering if there is a way to turn alcohol or another bacteria killing substance into a solid gel form, sort of like the gel you can use to clean a keyboard.
![Computer Cleaning Compound Super Clean Slimy][1]
> Source: Aliexpress.com [Computer Cleaning Compound][2]
I'm wondering if you could put either al... |
Is there a way to turn alcohol into a solid gel? |
I'll be having a national test tomorrow. I'd like to clarify so that I don't answered it wrong. Which of this following have higher boiling points? Alkanes, Alkenes, or Alkynes, and why? Thank you for answering. |
I'll be having a national test tomorrow. I'd like to clarify so that I don't answered it wrong.
**Question**: Which of the following has higher boiling points? Alkanes, Alkenes, or Alkynes? And why? Thank you for answering. |
We know that p-chloro phenol is more acidic than p-flouro phenol due to presence of vacant d orbitals.But then is it possible to say p-bromo phenol is more acidic than p-chloro phenol since it has vacant f orbitals also ? But i guess that's wrong,isn't it?Please give your suggestions. |
A reaction of importance in the formation of smog is that between ozone and nitrogen monoxide described by
$\ce{O3(g) + NO(g)->O2(g) + NO2(g)}$
the rate law for this reaction is:
rate of reaction = $\ce{k[O3][NO]}$
Given that k = 2.98 × 106 M–1·s–1 at a certain temperature, calculate the initial reaction ra... |
Calculate the number of moles of NO2(g) produced per hour per liter of air? |
We know that *p*-chlorophenol is more acidic than *p*-fluorophenol due to presence of vacant d orbitals. But then is it possible to say *p*-bromophenol is more acidic than *p*-chlorophenol since it has vacant f orbitals also? But I guess that’s wrong, isn’t it? Please give your suggestions. |
Is it possible to say p-bromophenol is more acidic than p-chlorophenol? |
How to determine whether the Enthalpy of formation is positive or negative? |
*Disclaimer*: **All of this "jazz" will be about reaching a mere rule-of-thumb. You can't just compare whole families of organic compounds with each other. There are more factors to consider than below, mostly based on isomerism notions. However, as most of the A grade exams emphasize on the lighter aliphatic compounds... |
How can we determine if the enthalpy of solution of a compound is positive or negative?
In order to make a clear idea about what I mean, take the following problem:
A 3.5 g sample of $\ce{NH4NO3}$ was added to 80. mL of water in a coffee cup calorimeter of negligible heat capacity. As a result, the temperature of... |
How to determine whether the enthalpy of solution is positive or negative by calorimetry? |
I have been asked the following question in my problem sheet:
![enter image description here][1]
[1]: https://i.stack.imgur.com/44S2h.png
The only differemce between reaction **A** and reaction **B** is the electron withdrawing group that stabilises the anionic transition state changes from $CN$ in reaction ... |
*Disclaimer*: **All of this "jazz" will be about reaching a mere rule-of-thumb. You can't just compare whole families of organic compounds with each other. There are more factors to consider than below, mostly based on isomerism notions. However, as most of the A grade exams emphasize on the lighter aliphatic compounds... |
*Disclaimer*: **All of this "jazz" will be about reaching a mere rule-of-thumb. You can't just compare whole families of organic compounds with each other. There are more factors to consider than below, mostly based on isomerism notions. However, as most of the A grade exams emphasize on the lighter aliphatic compounds... |
There are some seemingly contradictory things I'd like cleared up:
Second Law states: dSUniv = dsSys + dsSurr, and dSUniv is always positive in a spontaneous process.
First off, what does "spontaneous" truly mean? "It means the reaction occurs without any external energy input" - I've heard this one before, but i... |
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