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2answers
2k views

How to rationalise the difference in the melting points of acids and alcohols with inter molecular forces?

Acids: arachidic acid, palmitic acid, lauric acid, etc. Alcohols: butan-1-ol, pentan-1-ol, etc. The melting points of acids with $\ce{-COOH}$ at the end compared to melting points of alcohols, $\ce{...
0
votes
1answer
303 views

Purifying washing soda

I bought a box of A&H Washing Soda, the packaging of which implied that it was pure washing soda (sodium carbonate). On dissolving it in osmotically-purified water, however, I found that the ...
1
vote
1answer
10k views

Salicylic acid - polarity and solubility

Really confused about this, since there is carbon and two other types of atoms: should be polar, right? However, some people online say it is non-polar. Also, is it soluble in water?
0
votes
1answer
126 views

Is carbohydrate alcohol inebriant?

First of all, though I think that my question is related to this society, if you think reverse, tell me to delete the question: I would like to know if carbohydrate alcohol is inebriant; Can anyone ...
4
votes
2answers
138 views

Will all thermodynamic equations have a linear dependence with moles?

I'm taking chemical thermodynamics this semester, and currently seeing things like the Maxwell's Relations. My professor never uses explicitly the variable "n" and always works with molar quantities ...
1
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0answers
34 views

Does the added component (intended to disturb equilibrium) always ends up being more than the original amount, in the new equilibrium?

The title can be a little unclear. But what I am basically saying is say we add a reactant to a reaction to push the reaction forward toward the product side, that reactant which was increased in ...
19
votes
3answers
3k views

Conductivity as a function of acid concentration

I have conducted an experiment measuring the conductivity of both hydrochloric acid and sulfuric acid in solution respectively, with varying concentration. Wikipedia as well as a question on the site ...
5
votes
4answers
8k views

Can I react a Grignard reagent (ethylmagnesium bromide) with water and then ammonia? [closed]

I came across this question where I had to convert $\ce{CH3-CH2-Mg-Br}$ to $\ce{CH3-CH2-NH2}$. If I need to do so can I just react the given compound with water to get ethane and then react it with $\...
6
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1answer
734 views

Amine addition to nitro group

What is the mechanisms of this reaction? How feasible is this reaction? Can it happen under relatively mild conditions if it is intermolecular?
22
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1answer
11k views

Why is ethyne and not ethene used for welding?

Ethyne (Acetylene) is used with $\ce{O2}$ for welding. My question is that why is ethene not used? What properties of ethyne make it suitable for welding?
1
vote
0answers
36 views

Microorganism preventative solution safe for using on a roof and will last in the sun

Information is scarce in the roof cleaning industry and the big guys are making a killing selling chemicals that are harmful to the person using it and everything around the home. I would like to find ...
2
votes
2answers
673 views

Pathway from Sucrose to Cholesterol

I was reading Linus Pauling's book How to Live Longer and Feel Better, and in various places in the book he discusses a correlation between increased sucrose intake and increased blood plasma ...
9
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1answer
4k views

What will be the major product on chlorination of m-nitrophenol?

I came across a question asking for the major product on chlorination of m-nitrophenol. In my opinion the deactivating nature of nitro group should control the regioselectivity, but I found out the ...
1
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1answer
85 views

C-H bond energy in substituted methanes

What happens to the $\ce{C-H}$ bond strength in methane as the degree of halogenation is increased (e.g. from $\ce{CH4}$ to $\ce{CH3X}$ to $\ce{CH2X2}$...) Also, what is the effect of varying the ...
4
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0answers
81 views

Signs of Exchange and Correlation Potentials

The exchange and correlation potentials refer to those defined in density functional theory. (See also http://en.wikipedia.org/wiki/Local-density_approximation) Define the exchange potential as $V_{x}...
2
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1answer
6k views

Washing a solvent?

Why would you wash a solvent with $\ce{NaOH}$ solution? Does $\ce{NaOH}$ solution help water and solvent separate like $\ce{NaCl}$ solution does (salting out)? Would you wash with hot or cold $\ce{...
3
votes
2answers
109 views

condensation of tellurium on inside of ampoule?

After heating an ampoule of tellurium around its melting point in a furnace for about a day, I've noticed drops of the element on the upper inside surface of the ampoule, as if it condensed there. I'...
5
votes
1answer
791 views

Why is ionic strength (mu) calculated differently for these 2 examples?

In the following examples; I don't understand why $\ce{Na_3PO_4}$ is a much more complicated process when calculating $\mu$ compared to $\ce{NaH_2PO_4}$ and $\ce{Na_2HPO_4}$. Specifically, I don't ...
28
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2answers
2k views

Why is snow white?

I know that this is a rather ambiguous question; but my question is, whenever we take water and freeze it in the freezer, it still tends to stay clear. Since snow is just frozen water, why is it white?...
3
votes
1answer
128 views

When does a solute form ions?

If I have $\ce{HCl}$ and I put it in water, it will form ions. But, if I take $\ce{HCl}$ and put in benzene, it won't. How do you know that? If I had other substances, how would I know if it forms ...
15
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1answer
10k views

Regioselectivity in electrophilic substitution of pyrrole

In the electrophilic aromatic substitution (EAS) of pyrrole, why is the alpha position preferred over the beta position so much?
0
votes
1answer
454 views

How to apply the Henderson–Hasselbalch equation when adding KOH to an acidic acid buffer?

Will the Henderson–Hasselbalch equation be able to calculate the pH when you have an acidic solution and you add a basic solution? Will that be possible or can you only use it for adding an acid to an ...
-1
votes
1answer
85 views

Which is more: dissociated ions in water or undissociated? [closed]

While studying equilibrium we get to know that there are $1*10^{-7} \ce{~~OH-}$ and $\ce{H+}$ ions in pure water. However, I think there are more undissociated molecules.
6
votes
2answers
4k views

Should double or triple bonds have preference for low locants in IUPAC nomenclature?

Both double and triple bonds are present in the hydrocarbon shown above, which has the name hexa-1,3-dien-5-yne. Why is the numbering chosen such that the alkene has lower locants than the alkyne? Is ...
1
vote
1answer
31 views

Ideal gasses reaction under const temp and pressure

Conceptual problem: let $A + 2B \rightarrow C + 2D$ be a reaction under constant pressure (P) and temp (T), that goes all the way towards the products. A,B,C,D are ideal gases. let $\Delta H$ be the ...
5
votes
2answers
9k views

What is the meaning of parentheses in a condensed molecular formula?

In the formula $\ce{(CH3)3-C-CH(CH3)-CH2-CH3}$, what do the parenthesized portions represent? What is the molecular structure, and how do I name the compound?
0
votes
1answer
505 views

calculate the final concentration of this equation [closed]

A student mixed 260ml of 1.2 M lead(II) nitrate with 300ml of 1.90M potassium iodide. What is the final concentration of $\ce{NO3^{-}}$ ? the answer is 1.11M , but he used the moles of lead(II) ...
-1
votes
1answer
1k views

Effect of tear gas and laughing gas together

What will happen if someone uses tear gas, such as CS $(\ce{C10H5ClN2})$ and laughing gas, $\ce{N2O}$, in auditorium? Means will people start laughing and crying together? Or there will be other ...
2
votes
1answer
92 views

Finding equilibrium concentrations, trouble simplifying equation

For $\ce{CO (g) + H2 (g) <=> CH2O (g)}$ with Kc = 0.068 @ 273K initial concentrations being $\ce{[CO]}$ = 1.25M, $\ce{[H2]}$ = 2.00M, $\ce{[CH2O]}$ = 1.00M I did $\frac{1.00}{((1.25)(2.00)} = ...
1
vote
1answer
2k views

Converting mm Hg to mm H2O

So here's my problem: What is the osmotic pressure, noted in mm of $\ce{H2O}$, of a solution with 125 micrograms of vitamin B12 ($\ce{C63H88CoN14O14P}$) in 2.50 mL of $\ce{H2O}$ at 25 degrees Celsius....
1
vote
0answers
94 views

Conversion of standard InChI to InChI with fixed-hydrogen-layer

I am trying to convert a standard InChI string to a non-standard InChI string with fixed-hydrogen-layer: Standard InChI for Uracil: InChI=1S/C4H4N2O2/c7-3-1-2-5-4(8)6-3/h1-2H,(H2,5,6,7,8) Desired ...
1
vote
1answer
109 views

Why isn't this a compound? [closed]

I don't know what to call it I'll just provide a link. From what I can tell it is impossible, but why? http://www.chemicalize.org/structure/#!mol=structureId%3A1609384473364&source=calculate
5
votes
1answer
839 views

HOMO and LUMOs of Carbon based Compounds

Why are the HOMO and LUMOs often $\pi$ orbitals in carbon based compounds that contain multiple double bonds or conjugation such as ethene and butadiene?
5
votes
1answer
368 views

What is “mer”, the first ingredient in a type nail polish?

The first ingredient in a type of nail polish is "mer". What is this? Is it some kind of chemical? How is it used? How does it work?
17
votes
3answers
36k views

Why are water droplets shaped like that?

With nothing to do, I stared at the droplets that get condensed on the glass panel of my window. Upon examination, these droplets appear to be in some sorta pattern. There are big droplets as well as ...
0
votes
1answer
445 views

Molar mass of a mixture of two solids

I wonder, if I wanted to know the molar mass of a some white crystalline solid that is a mix of $\ce{C6H12O6}$ and $\ce{C12H22O11}$, would I just do this : $$170.1559 \; \ce{g/mol} + 343.2965 \;\ce{g/...
1
vote
1answer
306 views

Will trenbolone acetate in the presence of methanol yield trenbolone acetate if distilled water is subsequently added thereafter? [closed]

I have 2 grams of trenbolone acetate. I was told to add it to 20 ml of methanol. Then wait until it is fully dissolved. Then distilled water is to be added yeilding a precipitate that is supposed to ...
23
votes
3answers
72k views

What is the meaning of the “dot” notation in chemical formulas?

For example for 4 given elements A,B,C,D, what's the meaning of $\text{AB} \cdot x \text{CD}$?
1
vote
4answers
3k views

Equation for salt formation for ammonium oxalate?

I'm having trouble finding out the salt formation equation for $\ce{(NH4)2C2O4}$ I thought it was $\ce{NH3 + H2C2O4}$ but that doesn't seem to balance out. $\ce{HC2O4-}$ seems to work, but are ions ...
2
votes
0answers
56 views

Identify “decoupling sites” in glucose oxydase reaction

Given the following coupled reactions: $$\ce{glucose + O2 + H2O + glucose~oxydase -> gluconic~acid + H2O2}$$ $$\ce{H2O2 + TMB(star) -> TMB}$$ Identify: A potential reagent or ...
3
votes
2answers
683 views

How to report pH values?

I have measured the pH in the water-soluble fraction of a powder. I weighed in a certain amount of powder and a certain amount of water, and extracted the water-soluble fraction. I then measured the ...
7
votes
2answers
8k views

What is the molecular geometry of NHF₂?

I had to draw the molecular shape for $\ce{NHF2}$ as a Trigonal Planar like this But when I check to make sure it was right, I came across a source saying NHF2-difluoroammonia--tetrahedral, ...
0
votes
1answer
2k views

Finding Kp at another temp with /\Hrxn [closed]

Took a pic of the paper I tried it on it on, has the exact problem description written at top, and what I tried. Figured that would be easier then typing all that. The answer is supposed to be 2.0.
4
votes
2answers
898 views

How to calculate pH of a solution with two dominant equilibria?

Say you have acid X for which $K_a(X)$ = 1E-7 and acid Y for which $K_a(Y)$ = 0.8E-7. In separate solutions, it would be easy to calculate $[H^+]$ because there would be only one dominant equilibrium. ...
1
vote
1answer
83 views

Aluminum deoxidation gas

I am new to chemistry. I am looking for a gas that would de-oxidise aluminium. Which gases would work for that and at what temperature? Details: I need to sinter aluminium powder. But because the ...
1
vote
2answers
82 views

Concentration Inquiry

I just found a random example so I could highlight my inquiry: A chemist wants to make .5L of a 20M solutionusing $\ce{NaOH}$. The solution will be made from solid $\ce{NaOH}$ and water. How many ...
1
vote
1answer
181 views

Could PNP (Silicon) transistor be toxic when exposed to air\light?

The story goes as follow: While I was in the electronic room I got bored and crushed a PNP transistor (Model CDIL 2N2907) using a rotating pipe jaws just like in the picture bellow. Now, it took me ...
3
votes
1answer
1k views

Applying Raoult's Law to a condensed gas mixture

So, here's the question which I'm having trouble solving : Suppose that we condense a gas mixture. At 25 celsius, what will be the pressure of benzene and of toluene over the obtained liquid. We ...
3
votes
1answer
2k views

Why did the solution turn green?

I mixed L Arginine with l Citrulline in Hibiscus and green tea water which was red in color. Once the red liquid hit the mix of powdered Aminoacids the solution changed green. Can someone tell me why? ...
13
votes
3answers
17k views

Why is a hydroxyl group more activating than a methoxy group in electrophilic aromatic substitution?

Why is phenol more reactive towards electrophilic substitution than methoxybenzene? Isn't the lone pair on the methoxy group oxygen more available for participating in resonance into the ring than the ...

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