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19 views

Dissolving Metal Reduction of 4-Octyne to (E)-4-Octene and What Else?

I was reading Solomon's Organic Chemistry and came across the Dissolving Metal Reduction of 4-Octyne to (E)-4-Octene. (The same as can be found this question) But the book states that the (E)-4-...
1
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0answers
21 views

How to get the enthalpy of a reaction from the enthalpy of formations with Hess' law?

Let's consider a generic reaction: $$\sum_{i=0}^{i=I}n_{i}A_{i} \rightarrow \sum_{j=0}^{j=J}m_{j}B_{j} $$ where $n$ and $m$ are the stoichiometric coefficients, while $A$ and $B$ are reagents and ...
0
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0answers
26 views

Can sorbitol be used in place of sugar to produce ethanol? [on hold]

I was doing some reading on wine making, then I had an idea would it be possible to use sorbitol to make ethanol. From my reading, sorbitol is a sugar alcohol used as a sugar substitute. The only ...
0
votes
1answer
53 views

Intrahydrogen bonding [duplicate]

Is it okay to conclude that in 2-nitrophenol where intra hydogen bonding is experienced, two similar molecules are only held by the weak van der waal's forces and is the reason for it to have a ...
0
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1answer
69 views

Why could it be assumed that the standard enthalpy change is independent of temperature down to 25 °C?

For the reversible reaction of pyruvic acid to 2,2-dihydroxypropanoic acid, we calculated enthalpy using NMR and extrapolated from area (integration) and peaks etc. We then plotted $\ln K$ vs $1/T.$ ...
0
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0answers
24 views

How much more carbon dioxide does catalytic converters cause? [on hold]

A typical car has an engine control unit programmed to add more oxygen into the cylinder than is optimal for mechanical power efficiency, to enable combustion in the catalyzer. How much less carbon ...
2
votes
0answers
36 views

Can stimulated Raman processes be strong enough to drive out of equilibrium?

In the (spontaneous) Raman process, incident light $\hbar \omega_1$ scatters and transfers some energy $\hbar \omega$ to a vibrational excitation of molecule or solid. Typically this is a very rare ...
-2
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1answer
45 views

Why is FeCl3 (not AlCl3) used in chlorination of benzene? [on hold]

The book I am reading and on the internet everywhere I see FeCl3 is used for chlorination of benzene, can we use AlCl3 instead of FeCl3 because I assume it is working as Lewis base as anhy. AlCl3 work ...
0
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1answer
29 views

Aluminium Oxide as Dehydrating agent [on hold]

During preparation of alkenes from alcohols, we generally heat it in the presence of Al2O3 but how does aluminium oxide help in the reaction?
1
vote
1answer
98 views

Can acid-base reactions occur in a non-aqueous medium?

To better illustrate my question, allow me to refer to the case of ammonium chloride, formed through a classic acid-base reaction. The reaction between ammonia and hydrogen chloride to give ammonium ...
0
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0answers
23 views

Rust Spots on brand new porcelain toilet [on hold]

I work for a commercial mechanical contractor and we have a quite a few toilets installed on a facebook building that now have many little rust spots inside the bowl. Seems like the crews doing the ...
0
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0answers
14 views

Lewis Structures and electron distribution with oxygen atom

I am a novice in chemistry. I don’t understand the way Lewis structure and how electrons are shared between elements. For instance As we know, Oxygen has six valence electrons that means it has ...
-1
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0answers
23 views

Why are alkenes with more substituents more stable than those with fewer substituents? [closed]

The title is pretty self explanatory- I want to know, why do substituents make alkenes more stable?
-2
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0answers
11 views

Iodized salts titration with heat as independent variable [on hold]

I am doing the titration of iodized salts through freeing iodine atoms with hydrochloride acid and then titration gets with triosulfate with starch as indicator. My independent variable is how heating ...
0
votes
1answer
49 views

Why must there be degeneracy in the orbitals to have a Jahn-Teller effect?

Why is it the case that for Jahn-Teller effects to occur in transition metals there must be degeneracy in either the $\mathrm{t_{2g}}$ or $\mathrm{e_g}$ orbitals?
-1
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1answer
27 views

How is molefraction of a solution different in vapour state vs in solution vs vapour-liquid equilibrium?

I have this question we are given 'x' grams of benzene and 'y' grams of toulene, it is said that the vapour pressure of benzene is 75mmHG and that of toulene is 22mmHG and we are supposed to find mole ...
1
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0answers
22 views

What is the absolute configuration of carbon 5 in 5-bromo-2-methylhex-2-ene

I am trying to work out the absolute configuration around carbon atom 5 in 5-bromo-2-methylhex-2-ene. Could someone please let me know if my working is correct? Does the wedged bond from C4 to C5 ...
1
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0answers
52 views

Last step of proposed cubane synthesis

I was watching an online lecture on decarboxylation by soda lime and the first few examples were straight forward but after a while a felt that the questions couldn't simply have one effect and maybe ...
-4
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0answers
21 views

Why The Vilsmeier–Haack reaction of 2-phenylindole give pink color precipitate? [closed]

Tell me in brief about TLC of the product and solvent system ???
0
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0answers
21 views

Water Vapor Membrane [on hold]

Is there a plastic membrane that would allow water vapour to pass through, but not liquid water? Am looking into condensation harvesting in greenhouses to save water.
0
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0answers
13 views

Is there a method to calculate the concentration of a Sodium Sulphate solution from its electrical conductivity? [on hold]

I have a sodium sulphate solution which was made by reacting NaOH with CuSO4, I need to know its concentration to use it on a project, as soon as possible. I couldn't know for sure what was the mass ...
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0answers
16 views

How to check bond length in 2 bromo,1,3,5-trinitrobenzene [closed]

Please give me answer as possible as of this question.
-1
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0answers
26 views

Can an electron of a atom of restricted to 2nd shell be excited to third shell? [on hold]

If there is an electron in the 2nd shell in the s subshell, can it get excited to the 3rd shell or is it only limited to the p subshell? Like hydrogen has only the 1st shell but I've seen many ...
0
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0answers
7 views

(API) Assay & (API) Content Uniformity on tablets weight in pharmaceutical processes

From what know, Both assay and content uniformity are directly proportional to tablet weight. I want to know what’s the difference in these two different forms of API testing in tablets. I only know ...
1
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0answers
24 views

Enol percentage comparison between 1,3 diketones and 1,2 cyclopentadione [closed]

To what extent does 1,2-cyclopentadione exist in enol form? Will it be more than for 1,3 diketones? 1,3-Diketone with active methylene groups can form hydrogen bonds with a 6-membered ring structure. ...
1
vote
1answer
46 views

Why does copper have a high enthalpy of atomisation when it has a fully filled d sub shell? [on hold]

If I understood correct, the high energy of atomisation for d-block element comes from the ability to make many metallic bonds due to half electron filled d-orbitals, but it seems here that copper has ...
7
votes
1answer
884 views

How is taste of chemical compounds determined?

How do we know the taste of compounds, and their smell too, when some of them are poisonous. My textbook had that Lead is sweet in taste, but it's poisonous. So, how exactly do we determine their ...
1
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1answer
40 views

What is the relationship between enthalpy of atomisation and enthalpy of sublimation?

We know that we have to first break the metallic lattice to turn the metal into a gas and hence there should be some sort of relation between the two. I am trying to answer this question: The $E^θ(...
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0answers
21 views

What is the formula for vapor pressure of liquid related to surface tension of liquid?

What is the formula for vapor pressure of liquid related to surface tension of liquid? I know that if the surface tension increases, vapor pressure will decrease. Toluene evaporates faster than ...
1
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0answers
52 views

X-ray bombardment of CaCl2 and its resultant chemical changes

If one were to take $\pu{1 mol}$ of pure liquid Calcium Chloride (at $\pu{600 ^\circ C}$) and bombard it with $\pu{7.65 \times 10^{14} Ci}$ ($\pu{2.83 \times 10^25 particles}$) of x-rays ($\pu{75 keV}$...
-4
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0answers
26 views

If you breath on KOH would you get K2CO3 + H2O as a product? [closed]

In my AP Bio class we were looking at a reaction with CO2 and KOH and my biology teacher was wondering if breathing on KOH would produce solid K2CO3
-2
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0answers
24 views

What group on the periodic table would have the highest third ionization energies? Why?

I was answering questions about first and second ionization energy, seeing that alkali metals will go from low first ionization energies to having incredibly high second ionization energies because of ...
-2
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0answers
22 views

SN2 mechanism carbocation stability [closed]

Today in laboratory, we did an SN2 mechanism experiment using a variety of primary, secondary, benzyl, and tertiary carbocations with the leaving groups of Cl and Br. My tertiary carbocation barely ...
-3
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0answers
17 views

Do you put a bar above a percentage for sig figs? [closed]

Let's say my answer is 17% I have to round it to 1 significant digit, so I round it to 20% Do I put a bar over 2?
-2
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0answers
24 views

Left/right handed molecules? [closed]

Well, in this video https://www.youtube.com/watch?v=DJsJIVXkrGQ exactly at the minute 7:30 they explain 2 identycal molecules which one is left handed and the other right handed. 1) But, isn't it ...
0
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0answers
22 views

Combining two high-VP chemicals to get a low-VP mixture

I'd like to do a class experiment as a metaphor for human relationships. Two people each have a different chemical which evaporates quickly (at STP). There is one glass between them. If only one ...
-1
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0answers
36 views

Why is enol content more in 1,2-cyclopentanedione? [closed]

I am miserably confused on why would this compound exist in enol form, as I don’t see any driving force like aromaticity, extended conjugation or active methylene like conditions over here.
1
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0answers
53 views

What should be IUPAC name of given compound (see image)? [closed]

I think the name should be 1-carbamoylpentane-3-sulphonic acid, but the answer sheet mentions it as 2-carbamoylpentane-3-sulphonic acid: Can anyone please explain why the chain starting with methyl ...
1
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2answers
89 views

How can I find the Van der Waals constants (a and b) without any critical values?

I'm given a container of gas that is kept at constant temperature, and whose volume is decreased by applying pressure, from A to E, as the graph shows. I am given the temperature, the total moles in ...
0
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1answer
45 views

How to dispose of NaOH solution? [on hold]

I have a range of sodium hydroxide solutions with different concentrations. (from 1.0 mol dm^-3 to 0.5 mol dm^-3). The max volume of each is 100ml. How can you easily dispose of these? Can I pour them ...
-2
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0answers
43 views

Structure of perchloric acid [closed]

I was asked to draw structure of $\ce{HClO4}.$ I drew this: $$\ce{H—O—O—O—O—Cl}$$ But my teacher told me that it is wrong. He drew this: Why is my structure wrong and his correct?
-2
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0answers
22 views

Can a system be designed which equates reaction rates of endothermic reactions using a single power source? [closed]

My goal is to use a single source of heat in an experiment with 2 separate endothermic reactions. My hypothesis is that by conducting this experiment under water, the reaction time of both of the ...
0
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0answers
68 views

Oxidation of certain acids by potassium permanganate

Why does potassium permanganate oxidize formic acid and oxalic acid, but has no reaction with benzoic acid and acetic acid? The reactions were heated in a water bath (~70-80 °C). Oxalic acid had ...
-2
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0answers
15 views

Is it true the molecular structure of a styrofoam is similar with the fat deposits that causes atherosclerosis? [on hold]

A demo was exhibited showing fish oil on a styrofoam cup with hot water.... The exhibitor said the molecular structure of the styrofoamis similar to that of the fatty deposits causing atherosclerosis....
-1
votes
1answer
46 views

Why is the rate of effusion of a gas inversely proportional to (absolute) temperature? [duplicate]

(iv) Rate of effusion of a gas: The rate of passing of a gas through an orifice may be given as: $$r = \frac{PA}{\sqrt{2\pi RTm}}$$ where $P = $ Partial pressure of the gas $A = $ Area ...
-1
votes
0answers
11 views

Help with Alkyne Reactions for OCHEM [closed]

I am not too sure on how to solve these, I have a midterm coming up kinda soon and I need help reviewing these problems because my professor isn't handing out answer keys!
1
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0answers
19 views

Difference between Ziegler–Natta method and Phillips method [closed]

I have to compare the similarities and differences between the Zieglerr–Natta method and Phillips method of producing polyethylene. However, the only difference I can find is the difference in ...
1
vote
0answers
23 views

How does the phase inversion temperature of an emulsion depend on the oil - water ratio?

How does the phase inversion temperature (PIT) at the fish tail point in the fish-like diagrams of an oil - water - surfactant emulsion depend on the oil - water ratio? The HLD (hydrophilic-...
-3
votes
1answer
47 views

Calculating pressure [closed]

Calculate the pressure in Pa of a 760mm column of mercury when the density of Hg is 13.5951g/cm^3 at room temperature. P= dgh P=(0.0135951kg/cm^3)(9.81m/s^2)(0.76m) P=0.101 Where did I go wrong? ...
2
votes
2answers
58 views

Why does dipole must lie parallel to a rotation symmetry axis?

While studying group theory, I've got confused by the following statement: For a molecule to have a permanent dipole moment, it must have an asymmetric charge distribution. The point group of the ...

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