Raul Luciano
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What is the chemical formula of KIT-6?
11 votes

KIT-6 is a mesoporous silica, the chemical formula is the same for all silica which is $\ce{(SiO2)_n}$. The tridimensional structure though is usually represented as

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Help understanding this passage on optical activity
8 votes

I believe what is causing you confusion is the difference between optical activity and absolute configuration. A molecule with a single stereocenter such as limonene and carvone have two ...

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Reduction of alkyl halides to alkanes
5 votes

Your answer for question #3 is correct. However, there is a fundamental misconception you used in #1 and #2 that led to an incorrect answer. In your notes, it seems that electrons from the metal ($\...

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How does Ozone disinfect water?
5 votes

Ozone is a powerful oxidizer (redox potential of 2.07) and will kill bacteria and destroy viruses (not sure if I can say it kills viruses) by transferring oxygen atoms to them. It also decomposes in ...

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Mechanism for decarboxylation
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5 votes

In acidic media, the ester carbonyl will be protonated and the carbonyl carbon attacked by a water molecule. The intermediate will have a proton abstracted by a water molecule and the ethoxy group ...

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Why don't Gringard Reagents react with carbonyls at the alpha position?
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5 votes

It actually happens sometimes and you end up with the enolate being formed in appreciable amounts. But it depends on other adjacent substituents that can withdraw or donate electron density to the ...

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Mechanism of Hofmann Rearrangement Reaction
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4 votes

Water is present in large excess when compared to the amide, so it is statistically not likely that the proton would be removed from the amide rather then water. Even if it happens, proton exchange is ...

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Help on alternative terpene names and naming schemes
3 votes

Chemical nomenclature is officially defined by IUPAC (International Union of Pure and Applied Chemistry). You can find most IUPAC names for these terpenic compounds by searching their popular names on ...

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O-H infrared band dependence of alcohol concentration in water
3 votes

The water and ethanol -OH stretch bands are too close to be distinguished in a system with hydrogen bonding (liquid systems). You could expect a broadening in the signal as you add water since you ...

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Ring opening of epoxides
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3 votes

If you think about the quantities involved in this reaction, you'll realize why does the product contain the methoxy group and not the halide. Methanol is present in large excess since it is the ...

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How do you track Iodine on a black surface?
3 votes

I would spray some lead nitrate solution to the surface if I didn't care about it at all. It would form nice yellow crystals of lead iodide that could be seen on a black surface. Never tried it though....

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Which complex is the most stable?
3 votes

It is risky to predict just by looking at the structure, of course there is the ring size effect and one could easily conclude that $\ce{[Rh(Ph2PCH2CH2PPh2)3]3+}$ is the most thermodynamically stable ...

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Comparing relative negative inductive effect of substituents (dialkyl amine, amine, alkoxide, fluoride)
2 votes

The inductive effect is the polarization of σ (sigma) bonds within a chemical species caused usually by differences in electronegativity between the neighboring atoms. The higher the polarization it ...

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Reaction involving opening of epoxides
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2 votes

As you are dealing with Grignard reagents, the carbocation argument is inadequate since the reaction is in basic media (carbocations are brønsted acids, so they would be easily deprotonated to produce ...

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How does the 1.5 bond order of ozone contribute to its instability?
2 votes

A fractional bond order does not mean resonance, it's just a parameter obtained from molecular orbital theory accounting for the difference in population of electrons in bonding and antibonding ...

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Are SN2 reactions in equilibrium?
2 votes

When we talk about Sn1 or Sn2 reactions (and any other reaction to be honest), not only the reactants are crucial to describe what's going on but also the solvent you used. It is perfectly possible ...

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Chemistry underlying blacks spots in banana bread
2 votes

There are, at least, two reactions taking place and causing the brown colour of your bread. One is the oxidation of monophenols by an enzyme called PPO and the other is Maillard reaction, which is the ...

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Aluminum to prevent Iron corrosion
2 votes

Aluminum, just like zinc, is already widely used to coat iron surfaces to prevent corrosion (in the elemental form, or in combination with other metals, like zinc). You can deposit aluminum on ...

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How can I isolate glycolic acid from sugarcane juice?
2 votes

Ethylene Glycol was not used as a catalyst! Kataoka described in 2001 the production of Glycolic acid (GA) from ethylene glycol using glycol-oxidizing microorganisms isolated from soil, which is what ...

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What is HZSM-5?
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2 votes

According to this article(1), the difference between the zeolites HZSM-5 and ZSM-5 is that the first has a monoclinic and the second has an orthorhombic framework. (1) H. van Koningsveld, J.C. Jansen,...

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Monobromination of napthalene derivative
1 votes

You have electronically asymmetric rings. The right ring is deactivated by the carbonyl group that acts like an acyl group (remember that acyl groups are strong meta-deactivators). The left ring is ...

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Extraction of citric acid from lemon
1 votes

When you add calcium hydroxide to the sodium citrate solution, you end up forming tricalcium dicitrate In order to neutralize 1 mol of tricalcium dicitrate and form 2 mol of citric acid you need 3 ...

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Colour changes in coordination complexes
1 votes

Many things can happen when you heat a coordination complex: ligand loss, reactions in the ligand structure, loss of hydration water, isomerization, oxidation/reduction of the metal center etc. In ...

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Last step of nicotine extraction using DCM
1 votes

If you are worried only with DCM, then you should be fine since it is quite volatile. To be sure you have no DCM left in your nicotine leave it for a few days in a closed recipient filled with some ...

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Does rubber use one or two sulfur atoms to crosslink?
1 votes

According to the Polymer Database, the sulfur bridges formed in the vulcanization process of natural latex are usually comprised of 4-6 sulfur atoms, although this polyssulfide chain can be shorter ...

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positive charge on oxygen of carbonyl group in acetic acid
1 votes

The carbon atom does not have a full positive charge like a carbocation. What happens when a carbon atom is bound to a more electronegative element such as oxygen, is that the electron density from ...

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I'm looking for something as strong as Acetone
1 votes

Mineral oil is often used to remove nail polish. Give it a try (J&J has a great one for babies with a soft smell).

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What is the liquid coming out of these Duracell batteries?
1 votes

Well, it depends on which type of battery you have. Alkaline batteries such as Duracell Coppertop usually leaks KOH (potassium hydroxide) under conditions of misuse as a white foam. However, KOH is ...

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Potential energy versus reaction coordinate (graph of Gibbs free energy)
1 votes

There is a long explanation for that, however in short they are not the same thing. Free energy relates to thermodynamic systems with many particles and is governed by Boltzmann's distribution, a sum ...

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Mechanism of Dehydrogenation Reaction
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1 votes

The answer you seek can be found here uwyo.edu/roddick/site/alkane_dehydrogenation.html , the catalytic cycle of dehydrogenation of alkanes by Iridium complexes does not follow a simple syn addition ...

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