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If the manometer were open at both ends, the two fluid levels would be identical. If the bulbed gas were at ambient pressure, ditto. That the fluid is higher at the bulb end says the pressure in the bulb was lower than ambient pressure, and lower still for the weight of the differential fluid head, height times densit... |
First off this isn't really homework it's a practice problem for an upcoming exam.
I'm doing really well in the class and feel like I understand all the material but this problem is stumping me. This is because I feel my method for solving it is correct and I've checked my calculations yet I can't get the right answ... |
The crystals that I am synthesizing use two different stabilizers CTAB and SDS, but they say one is used as a surfactant and since they are both stabilizers what is the need for both? |
What is the difference between the roles of a surfactant and a stabilizer in the process of nanocrystal growth? |
First off this isn't really homework it's a practice problem for an upcoming exam.
I'm doing really well in the class and feel like I understand all the material but this problem is stumping me. This is because I feel my method for solving it is correct and I've checked my calculations yet I can't get the right answ... |
First off this isn't really homework it's a practice problem for an upcoming exam.
I'm doing really well in the class and feel like I understand all the material but this problem is stumping me. This is because I feel my method for solving it is correct and I've checked my calculations yet I can't get the right answ... |
I feel my method for solving it is correct and I've checked my calculations yet I can't get the right answer.
--------------------
Nitrogen and oxygen gases may react to form nitrogen monoxide. At 1500 °C, $K_c$ equals 1.0E-5.
$\ce{N2_{(g)} + O2_{(g)} <=> 2 NO_{(g)}}$
If $2.75 \times 10^{-2}$ mol $N_2$ ... |
How do I determine the equilibrium concentration given Kc and the concentrations of component gases? |
![enter image description here][1]
[1]: https://i.stack.imgur.com/UN7B2.jpg
I have a basic question on a closed manometer:
I see that in this case the pressure of gas is lower than that of the liquid, which is why the liquid is higher on the left side. Now, what I don't understand is why do we say that the... |
What does negative pressure mean in the context of this manometer? |
I just electrolyzed water with $\ce{NaHSO4 -> HSO4- <=> H+ + SO4^2-}$ with copper electrodes.
At the anode this reaction happened:
> $\ce{Cu -> Cu^2+ + 2e-} \hspace{26 mm} E_0 = -0.34V$
> $\ce{Cu^2+ + 6H2O -> [Cu(H2O)6]^2+}$
Can anyone confirm this last reaction? There was a blue-greenish substance fall... |
What is made at the copper cathode when electrolyzing water? |
There are a number of things I don't understand about ionic equations.
First off, when you do net ionic equations, is it correct that you're only focusing on precipitates? The way I understood it, you put "no reaction" if there are no solid or gaseous products. To clarify, if all of the products of the reaction are ... |
Which ions are accounted for in total and net ionic equations? |
Look at your redox potentials for the half reactions. 12V is tremendous overkill. At the cathode (reducing) you will make hydrogen to which copper is inert. Could you reduce sulfate to sulfide or sulfur and have that react with copper? CuS is black.
At the anode (oxidizing) you will oxidize water to oxygen - but... |
What are the products of the dissociation of NaHCO3 in water? What is the relative pH of the solution? |
Is not so intuitive as it seems and your questions are all legitimate questions.
But I think sometimes even good argumentations can't be used as evidences in chemistry. So we can start looking point by point yours.
----------
#$\ce{NaHCO3}\rightarrow \ce{Na+}+\ce{HCO3-}$, but that one doesn't involve water at... |
This problem has been troubling me a little bit.
So in this problem they gave me a reagent and they want me to figure out the end product.
the reagent is:
2-butene reacting with sodium tert-butoxide and CH3Br3.
Now, what I was thinking was that the oxygen would pull the hydrogen from CH3Br3 making a posit... |
This problem has been troubling me a little bit.
So in this problem they gave me a reagent and they want me to figure out the end product.
the reagent is:
2-butene reacting with sodium tert-butoxide and CHBr3.
Now, what I was thinking was that the oxygen would pull the hydrogen from CHBr3 making a positiv... |
Hello I am looking for this information and I did not find anything, the closest thing I have found it is Fluorocarbon, but I think it is wrong, does anybody know?.
Help really appreciated I am still looking for this |
name of a pharmaceutical drug used in dentistry that has Ionic bonding? and how this bounding is made? |
Is the name "Dihydrogen monoxide" actually what chemists would use to refer to H2O (assuming there was no common name, "water")?
Of course, this is all over the internet. I'm a little skeptical though because the similar chemical H2S is called "hydrogen sulfide", not "dihydrogen monosulfide". |
Chemical Potential of Idea gas? |
We've started learning about NMR in my ochem class and my instructor told us that in Hydrogen NMR an alcohol can have a fairly wide range of possible values - usually from about 2 to 5. He said that because of this the actual ppm value is not very diagnostic - but the fact that alcohols tend to have a thicker peak is.... |
Does kosher salt has different structure than regular table salt or it is issue of crystals size?
Why some recipies want us to use one instead another? |
The fluorocarbons that you mentioned do have polarized $\ce{C-F}$ bonds, but no ionic bonds. If you think *ionic*, think salts.
I'm not a pharmacologist, but what about the local anestethics used at the dentist? Lidocaine (**1**), mepivacaine (**2**), and articaine (**3**) are frequently used.
![local anesthetic... |
The fluorocarbons that you mentioned do have polarized $\ce{C-F}$ bonds, but no ionic bonds. If you think *ionic*, think salts.
I'm not a pharmacologist, but what about the local anestethics used at the dentist? Lidocaine (**1**), mepivacaine (**2**), and articaine (**3**) are frequently used.
![local anesthetic... |
The question is:-
> Iodine dissolves in a variety of solvents forming solutions that are
> purple, brown or any intermediate shade. This property is due to:-
>
> 1. Hydrolysis of iodine
> 2. Formation of crystalline adducts
> 3. Charge transfer between $\ce{I-I^-}$ and the solvent
> 4. Charge tranfer... |
This is going to seem like a rather daft question, but what is the definitive half-live for protactinium-234 (234Pa)? I'm seeing lots of different answers in various academic papers etc.
For instance, in Bonotto & Andrews (2000) the half-life of protactinium-234 (234Pa) is given as 1.18 minutes, but in Edwards et a... |
> So which one is it?
Both! Proactinium-234 exhibits **nuclear isomerism**. The metastable form $\ce{^{234m}Pa}$ has a half-life time in the range of 1 min, whereas $\ce{^{234}Pa}$ shows a half-life time around 6 hrs.
|
> So which one is it?
Both! Proactinium-234 exhibits **[nuclear isomerism][1]**. The metastable form $\ce{^{234m}Pa}$ has a half-life time in the range of 1 min, whereas $\ce{^{234}Pa}$ shows a half-life time around 6 hrs.
[1]: http://en.wikipedia.org/wiki/Nuclear_isomer |
This is going to seem like a rather daft question, but what is the definitive half-live for protactinium-234 (<sup>234</sup>Pa)? I'm seeing lots of different answers in various academic papers etc.
For instance, in Bonotto & Andrews (2000) the half-life of protactinium-234 (<sup>234</sup>Pa) is given as 1.18 minute... |
This problem has been troubling me a little bit.
So in this problem they gave me some reagents and they want me to figure out the end product.
The reagents given are:
2-butene reacting with sodium tert-butoxide and $\ce{CHBr3}$.
Now, what I was thinking was that the oxygen would pull the hydrogen from $\c... |
Iodine in an inert solvent is purple. Electron donation alters that. Linear starch (amylose)-iodine is dark brown. Branched starch (amylopectin)-iodine is red. The Wikipedia page shows iodine in chlorinated solvent (very weak electron donation) then addition of strong electron donor triphenylphosphine.
If an ele... |
Suppose we have a T-S diagram of some vapor thermodynamic cycle , say the rankine cycle , and we are interested for example in the composition of the liquid and the vapor in the middle of the condensation process ; knowing only the entropy of both the liquid and vapor at that point (or the enthalpy) , how exactly do w... |
Vibrational frequency computations provide the magnitudes of vibrational frequencies for each vibrational mode of a molecule ($3N-6$ degrees of freedom for non-linear molecules and $3N-5$ for linear molecules). Sometimes these magnitudes can be non-real (i.e. imaginary). This is common when characterizing a transitio... |
Vibrational frequency computations provide the magnitudes of vibrational frequencies for each vibrational mode of a molecule ($3N-6$ degrees of freedom for non-linear molecules and $3N-5$ for linear molecules). Sometimes these magnitudes can be non-real (i.e. imaginary). This is common when characterizing a transitio... |
I propose to carry out an electrolytic etch on a stainless steel plate.
One of electrodes must be the stainless steel plate which is being etched and the surface layer must be removed.
I'm aware such an electrolytic etches can produce harmful by-products such as Chlorine (NaCl electrolyte), Chromium compounds and... |
How can I safely carry out an electrolytic etch on stainless steel without producing relatively harmful by-products? |
I propose to carry out an electrolytic etch on a stainless steel plate like so:
One of electrodes must be the stainless steel plate which is being etched and the surface layer must be removed.
I'm aware such an electrolytic etches can produce harmful by-prod... |
In my organic chemistry class there are several reactions that I've been told are generally conducted at -78 C, which is apparently also the temperature of dry ice in acetone. This is all well and good, but I don't really get what that actually means... Do you put the dry ice in the acetone and then toss in your react... |
Reading about the light emitting reaction of luciferin + ATP, catalysed by luciferase I am confused about the following.
On this webpage http://en.wikipedia.org/wiki/Luciferase the partial formula is written as:
**luciferin + ATP → luciferyl adenylate + PPi** which seems to me like a one way reaction.
But on sea... |
Can luciferin + ATP → luciferyl adenylate + PPi be reversed? |
Reading about the light emitting reaction of luciferin + ATP, catalysed by luciferase I am confused about the following.
On [this webpage][1] the partial formula is written as:
luciferin + ATP → luciferyl adenylate + PPi
which seems to me like a one way reaction.
But on searching on Google "luciferase ATP e... |
Reading about the light emitting reaction of luciferin + ATP, catalysed by luciferase I am confused about the following.
On [this webpage][1] the partial formula is written as:
luciferin + ATP → luciferyl adenylate + PPi
which seems to me like a one way reaction.
But on searching on Google "luciferase ATP e... |
I've been trying to make Sodium dichromate Na2Cr2O7 by following these steps:
- Dissolve an inox spoon in H2SO4
- Filter the solution
- Dissolve the obtained sludge in NaClO
- Heat the solution until slurries appear
- Filter the solution
The solution I obtained was yellowish (light yellow), I tried to add som... |
I've been trying to make Sodium dichromate $\ce{Na2Cr2O7}$ by following these steps:
- Dissolve an inox spoon in $\ce{H2SO4}$
- Filter the solution
- Dissolve the obtained sludge in $\ce{NaClO}$
- Heat the solution until slurries appear
- Filter the solution
The solution I obtained was yellowish (light yellow... |
Is melting of NaCl a physic and chemical process? |
Is there a stable molecule with total number of electrons equal to 13? Molecule can be either organic or inorganic |
Is melting of NaCl a physical and chemical process? |
What is the Melting point of diamond? |
Diamond (Carbon) does not melt at 1 atm. It sublimes to vapor.
Using Carbon's theoretical phase diagram below (from Wikimedia), "liquid diamond" could be achieved at about 10 GPa and 5000K, which is equal to almost 99 thousand atmospheres and 4726.85°C.
![enter image description here][1]
**Edit:**
In fact, ... |
Please note that I have never done this.
But are you sure that you want to rely on approximation/assumptions?
I realize that it needs additional changes to the experimental setup, but is measuring the ethanol concentration out of question? Gas sensors for ethanol are commercially available and a setup, in which ... |
In my textbook it says that the maximum number of electrons that can fit in any given shell, is given by 2n². Which would mean 2 electrons could fit in the first shell , 8 could fit in the 2 shell , and 18 in the 3rd shell, and 32 in the 4th shell.
However, I was previously taught that the max# of electrons in firs... |
I've found a Dover edition copy of Pauling's General Chemistry in the bookstore near me. I'd like to know if it's still readable today, I mean, is it still up-to-date? I have no background in chemistry, but the book was cheap and it seems to be a nice read. |
Is Linus Pauling's General Chemistry still readable and up-to-date today? |
This question was triggered by another question on this site, about molecules with a [total number of 13 electrons][1].
I couldn't think of any (except the boring answer of $\ce{Al}$), and the answers to the question are all about **radicals**, instead of 'normal' molecules. So that got me thinking: are all organic ... |
Are all organic molecules with odd-numbered electron count radicals? |
This question was triggered by another question on this site, about molecules with a [total number of 13 electrons][1].
I couldn't think of any (except the boring answer of $\ce{Al}$), and the answers to the question are all about **radicals**, instead of 'normal' molecules. So that got me thinking: are all organic ... |
Have you learned about [quantum numbers](http://en.wikipedia.org/wiki/Quantum_number#Traditional_nomenclatures) yet?
>If not...
Each shell (or energy level) has some number of [subshells][1], which describe the types of atomic orbitals available to electrons in that subshell. For example, the $s$ subshell of any... |
Shells and orbitals are not the same thing. In terms of quantum numbers, electrons in different shells will have different values of principal quantum number *n*.
To answer your question...
In the first shell (n=1), we have:
- The 1s orbital
In the second shell (n=2), we have:
- The 2s orbital
- The 2p ... |
A frozen urine specimen is required for an organic acids lab test, but the urine refuses to freeze after 4 days in a regular freezer turned as low as it will go. What would explain this, and how cold might it need to be to freeze? |
What would explain urine that resists freezing? |
From Practical skills in Biology by Allan Jones et al.
> At high concentrations of certain ionic solutes, $\gamma$ (activity
> coefficient) may increase to become greater than unity.
My questions : If activity coefficient $\gamma$ $=$ $ {a}/{[C]} $ where $a$ is activity which signifies *effective* concentrati... |
Shells and orbitals are not the same thing. In terms of quantum numbers, electrons in different shells will have different values of principal quantum number *n*.
To answer your question...
In the first shell (n=1), we have:
- The 1s orbital
In the second shell (n=2), we have:
- The 2s orbital
- The 2p ... |
The pattern of maximum possible electrons = $2n^2$ is correct.
Also note that Brian's answer is good and takes a different approach.
Have you learned about [quantum numbers](http://en.wikipedia.org/wiki/Quantum_number#Traditional_nomenclatures) yet?
>If not...
Each shell (or energy level) has some number ... |
I learned that if concentration of reactants or products is changed, the position of equilibrium changes but value of $K_c$ remains the same.
This just does not make intuitive sense to me... I mean whatever concentration of reactants I start with does not matter, $K_c$ remains same....?
Also, can someone please ela... |
What is the name of this molecule? (C8O3H12N) |
What is the name of this molecule? (C8O3H13N) |
I know that usually more electronegative anions would displace less electronegative anions but is there a way to get different anions to "share" a cation? |
Is it possible to create a salt with multiple anions with only one cation(e.g. CaBrCl)? |
I know 3 types of unit cells, the simple cubic, the body centered and the face centered. But what is "hexagonal unit cell“， why does it have a hexagon base while others are all cut into a cubic? And how to calculate how many atoms in every primitive hexagonal unit cells? |
Sure, why not? In the bad old days geology claiming isomorphous substitution had a hissy fit with chemistry claiming exact stoichiometry. Rochelle salt is potassium sodium tartrate. Potassium aluminum sulfate (alum) is often doped with colored transition metal ions substituting for some of the aluminum (chrome alum).... |
A student determined the Ca^2+ ion content in a sample of nonfat dry milk. For complete titration of the Ca^2+ ion present, a sample weighting 1.483 g required 41.33 mL of 1.183 x 10^-2M EDTA solution. Calculate the mass of Ca^2+ ion in the titrated sample.
So I did:
(41.44 mL) = 0.04133 L
(1.183 x 10^-2)(0.04... |
Does supersaturated caffeine polymerize? |
How do I convert Nitrobenzene to m-nitro Benzyl alcohol using 2 steps? |
How do I convert Benzoic Acid to m-nitro Benzyl alcohol using 2 steps? |
1. Use the meta-directing effect of $\ce{-COOH}$: nitrate benzoic acid first.
2. Reduce *m*-nitrobenzoic acid with $\ce{LiAlH4}$. The nitro group is not attacked, but when you calculate the equivalents of $\ce{LiAlH4}$ needed, don't forget that you are reacting an **acid** with a **hydride**.
<hr>
**Edit 1**... |
I know 3 types of unit cells, the simple cubic, the body centered and the face centered.
But what is a *hexagonal* unit cell, and why does it have a hexagon base while others are all cut into a cubic? And how can I calculate the number of atoms in every primitive hexagonal unit cells? |
A student determined the $\ce{Ca^{2+}}$ ion content in a sample of nonfat dry milk. For complete titration of the $\ce{Ca^{2+}}$ ion present, a sample weighting 1.483 g required 41.33 mL of 1.183 x $10^{-2}$M EDTA solution. Calculate the mass of $\ce{Ca^{2+}}$ ion in the titrated sample.
So I did:
(41.44 mL) = 0.... |
> A student determined the $\ce{Ca^{2+}}$ ion content in a sample of nonfat dry milk. For complete titration of the $\ce{Ca^{2+}}$ ion present, a sample weighting $1.483 ~\mathrm{g}$ required $41.33 ~\mathrm{mL}$ of $1.183 \times 10^{-2} ~\mathrm{M}$ EDTA solution. Calculate the mass of the $\ce{Ca^{2+}}$ ions in the t... |
Consider this reaction of alpha decay: _( Note: The elements are written as follows -> **Element Name(Mass Number, Atomic Number)** )_
Ra(222, 88) -----------> Rn(218, 86) + He(4, 2)
So the question is that whether or not the electrons also get distributed in the reaction like the nucleons?? |
Does the electrons also get distributed in an alpha decay? |
Consider this reaction of alpha decay:
$$ \ce{^{222}_{88}Ra -> ^{218}_{86}Rn + ^4_2 He} $$
My question is, whether or not the electrons also get distributed in the reaction like the nucleons? |
Are the electrons also distributed for the alpha decay? |
Why does the cathode ray tube glow at 0.1 atmospheric pressure and does not glow completely at 0.001 atmospheric pressure rather just have some fluorescence at the anode? According to me see at first at normal pressure it does not glow then if you decrease the pressure all of it glows and then if you decrease the press... |
Why does the cathode ray tube glow at 0.1 atmospheric pressure and does not glow completely at 0.001 atmospheric pressure rather just have some fluorescence at the anode? According to me see at first at normal pressure it does not glow then if you decrease the pressure all of it glows and then if you decrease the press... |
Does anyone know whats are the intermediate calculations to obtain the equation 1.4.14? Taken from Fundamentals and Applications (Bard) page 31![Fundamentals and Applications (Bard) pg. 31][1]
[1]: https://i.stack.imgur.com/qtZzl.jpg |
Please first see this [http://en.wikipedia.org/wiki/Gas-filled_tube][1].
The gas pressure influences the following factors:
- breakdown voltage
- current density
- operating voltage
- backfire voltage
- tube lifetime (lower pressure tubes tend to have shorter lifetimes
due to using up of the gas)
-... |
Does anyone know whats are the intermediate calculations to obtain the equation 1.4.14? Taken from Fundamentals and Applications (Bard) page 31![Fundamentals and Applications (Bard) pg. 31][1]
To be more precise, how to obtain (1.4.14) from $\frac{nFAm_O}{nFAm_R}=\frac{i_l-i}{i}$
[1]: https://i.stack.imgur.com/qt... |
Why does the cathode ray tube glow at 0.1 atmospheric pressure and does not glow completely at 0.001 atmospheric pressure if only it has some luminescence at the anode? According to what I saw, at normal pressure it does not glow, but if you decrease the pressure all its volume glows and further pressure decrease lead... |
I am considering the cathode ray tube of the set up, when the cathode rays were discovered
Voltage = Very High<br />
Gas = any<br />
Atmospheric Pressure = We change
(In the following example i am just changing the atmospheric pressure everything else is kept same)
At <br />
1 atmospheric pressure (atm) -> ... |
In the organic chemistry textbook by Clayden et al. they mention that the reaction of (E)-methyl 3-(furan-2-yl)acrylate in acidic methanol yields dimethyl 4-oxoheptanedioate without providing the reaction mechanism and leaving it to the reader to figure it out:
![enter image description here][1]
I tried for over ... |
What's the mechanism of the reaction of (E)-methyl 3-(furan-2-yl)acrylate in acidic methanol? |
In the organic chemistry textbook by Clayden et al. they mention that the reaction of (E)-methyl 3-(furan-2-yl)acrylate in acidic methanol yields dimethyl 4-oxoheptanedioate without providing the reaction mechanism and leaving it to the reader to figure it out:
![enter image description here][1]
I've tried for ov... |
Does anyone know what the intermediate calculations are to obtain equation 1.4.14? Taken from Fundamentals and Applications (Bard) page 31![Fundamentals and Applications (Bard) pg. 31][1]
To be more precise, how to obtain (1.4.14) from $\frac{nFAm_O}{nFAm_R}=\frac{i_l-i}{i}$
[1]: https://i.stack.imgur.com/qtZzl.j... |
How do I derive the Nernst equation in the case in which R is absent? |
What is the cost of 1.00 g of calcium ions as provided by this brand of dry milk? |
I have read that combining the DC current with a high frequency AC current, the electrolysis of water speeds up. How does this work? Does the "extra energy" come from less heat production? What frequency is needed? |
How does High Frequency water electrolysis work? |
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