Your Question About Easy Weight Loss

Linda asks…

why would you get 0% yeild when you extract you fischer esterification with diethyl ether?

In a fischer esterification experiment using formic acid and methyl alcohol a student got a 0% yeild. Main difference with her experiment and other’s experiment was that she extracted her solution with diethyl ether on top of water and sodium bicarbonate (each separately).

weight loss cardiff answers:

Two reasons come to mind. First, the product, methyl formate, would be very soluble in water, and highly resistant to solvent extraction. Second, the boiling point of methyl formate is quite low, 32 °C, so any product that might have been successfully extracted was probably lost when the ether was stripped.

Personally, I would have fractionally distilled the reaction mixture after neutralization of the acid catalyst, to get the product.

Mark asks…

Solubility of LiAlH4 and KAlH4 in diethyl ether?

Qualitatively predict the solubility of LiAlH4 and KAlH4 in diethyl ether and provide a concise explanation of the predictions made.

weight loss cardiff answers:

LiAlH4 is more covalent in general than KAlH4; therefore the solubility in ether will be much higher for LAH than for KAH.

William asks…

Can you please help me find the IR spectral charts for these compounds?

n-butane, ethanol, acetic acid, and diethyl ether. Yes, I am asking for help on my homework, but I have tried desperately to find these. I’m not interested in data tables, but a visual chart. There cannot be any functional groups intertwined with the readings. Only pure readings of the above choices.

Thank you!
plz, no sites or directories.

weight loss cardiff answers:

I refuse to do your work for you, but I’ll give you simple steps.

1. Go to http://www.sigmaaldrich.com/
2. Look up your compound.
3. On the right hand side, there should be Literature NMR and IR Spectra linked.

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Your Question About Easy Weight Loss

Steven asks…

Which of the following is a polar aprotic solvent?

A) CCl4
B) NH3(l)
C) Diethyl ether
D) 2-methyl-2-propanol
E) 2-methylhexane

My line of thinking was to cross out all nonpolar substances. A, C, and E are automatically out. (Hopefully the ether is nonpolar, I think they are, or at the most, very slightly polar.. oh well.)

Then I’m left with 2-methyl-2-propanol and ammonia. 2-methyl-2-propanol is slightly polar, but it may display hydrogen bonding, so it’s protic.

The ammonia is polar, and also displays hydrogen bonding, seeing as the nitrogen is highly electronegative.

Which leaves the question.. where has my logic failed?

weight loss cardiff answers:

Your logic has failed in crossing off ether! It is a bent molecule, and polar.

Mary asks…

What is the product when the following compound is oxidized?

——-OH
C-C-C-C-C

A. diethyl ketone
B. 2-pentene
C. pentanal
D. diethyl ether
E. pentane

weight loss cardiff answers:

Lol…wtf is that? 3-pentanol, right?

If it’s oxidize, you get 3-pentanone, ie. Diethyl ketone.

Linda asks…

During extraction, which of these substances would be in the top layer when added to the same container?

A. Diethyl ether/water

B. Dichloromethane/water

If you also know why, feel free to explain a little. Thanks!

weight loss cardiff answers:

Diethyl ether and Dichloromethane would be in the top layer. Both of these chemicals have poor water solubility and float on the top of the water layer. (You know, like “oil and water don’t mix.”) The top layer is also called the “oil layer” for this reason.

If you have a chemical that you want in the water layer that’s more soluble in DiEE or DCM, washing and agitating it will mix the chemicals and ‘pull out’ your desired chemical into the oil layer, trapping it there. That’s why you shake the extraction funnel so many times. Since the oil layer sits on top, later on you can allow it to settle and then just turn the stop cock and run off the water layer.

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Lizzie asks…

What is worse, the smell of chloroform or ether?

Personally, I can’t stand the smell of diethyl ether…but chloroform isn’t too bad.

weight loss cardiff answers:

My victims tell me it`s chloroform..

Maria asks…

Which of these molecules cannot form hydrogen bonds?Ethanol,Diethyl ether,water,ammonia or ethylene glycol?

I have been struggling with this question on an assignment for school: Which one of these following molecules cannot form hydrogen bonds? Ethanol, diethyl ether, water, ammonia or ethylene glycol?
Can you help?!

Thank you 😀

weight loss cardiff answers:

All of them except diethyl either – the H atoms in this molecule are bonded to C atoms and not to O atoms

Mandy asks…

One method of synthesizing ethers is by removing a water molecule from two primary alcohols. Use structural?

formulas to propose an equation for the synthesis of diethyl ether.

weight loss cardiff answers:

Ethanol ( ethyl alcohol ) is CH2CH2OH

Place two of these molecules so that 1 molecule of water can be removed

CH3CH2O[H HO]CH2CH3 Note that I have put [ ] around the molecule of water. Remove this and write down what is left:
CH3CH2OCH2CH3 diethyl ether

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Your Question About Easy Weight Loss

Susan asks…

What safety precautions should one take when using chlorinated solvents for extraction?

Also, what is the practical advantage of using dichloromethane (density=1.325g/ml) over diethyl ether (density=0.706glml) for extracting organic compounds from an aqueous solution using a separatory funnel?

weight loss cardiff answers:

The lab should be well ventilated, as chlorinated solvents are toxic and induce nausea and drowsiness.

Since CH2Cl2 is denser than water, the organic layer will be the lower layer. This can be drained off and more, fresh solvent can be added to the separatory funnel for a 2nd extraction.

If diethyl ether is used, the organic layer is the upper layer. The aqeuous layer has to be drained off, the organic layer decanted out of the top and, if a 2nd extraction is to be done, the aqueous layer has to then be returned to the separatory funnel. More transfers of layers means more losses of material.

Donald asks…

How to do you separate a mixture of benzoic acid and 2-naphthol?

Do we used sodium bicarbonate or diethyl ether?

weight loss cardiff answers:

First dissolve a few grams of the mixture in diethyl ether.

Next, extract the benzoic acid into an aqueous layer by adding saturated NaHCO3 to the ether solution in a separatory funnel. This should be done 3 times with small amounts of the saturated NaHCO3 solution. The benzoic acid will react with the NaHCO3 to form a salt that is soluble in the aqueous phase. The aqueous phase will be on the bottom because water is more dense than diethyl ether. Remember to vent the extraction flask often to reduce pressure due to CO2 gas being released in the chemical reaction. 2-naphthol will not dissolve in saturated NaHCO3.

Reaction: C6H5COOH(aq) + HCO3^-(aq) –> C6H5COO^-(aq) + CO2(g) + H2O

Recover the 2-naphthol by removing the ether. If you did a good job of extracting the solid should be fairly pure. You can check this by obtaining a melting point of the product after drying.

Recover the benzoic acid by adding concentrated HCl (caution) to the aqueous solution. The volume of acid you add depends on the amount of benzoic acid you have in the aqueous phase.

Reaction: C6H5COO^-(aq) + H3O^+(aq) –> C6H5COOH(s) + H2O(l)

The pH of the solution can be checked using pH paper as you add more concentrated HCl (add drop by drop) When the pH of the solution reaches about 1 then you can stop adding the acid and cool down the benzoic acid solution in an ice water bath. After the solution is cooled to about 0 degrees Celsius then you should use vacuum filtration to recover the product. Allow the product to dry in your equipment cabinet by leaving the filtered solid on a watch glass.

Hope this is helpful to you. JIL HIR

Ruth asks…

Solubility Tests – How does a solubility test confirm the presence of an acid or a base.?

I did an extraction experiment of an acid/base from a neutral. We first had to determine whether an acid or a base was present. So how does the solubility test determine that? The test was done in diethyl ether (which my base dissolved in), water, HCl, and NaHCO3.

Thanks!

weight loss cardiff answers:

Acids are more easily dissolved in basic solution, bases are more easily dissolved in acidic solution.

Dissolving is an equilibrium reaction so partial solubility in one of the solutions will give an indication. If your unknown did not fully dissolve in acid or base this may be just an indication it is not a strong acid/base. Dissolving in diethyl ether is just an indication of the organic nature of your unknown. Details of solubility testing in this website [1]

Good luck 🙂

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