Reactions Of Organic Compounds: September 2010

Tuesday, September 28, 2010

What is the use of fenton's reagent?

Fenton's reagent is used for the oxidation of ethylene glycol to glycol aldehyde.

Fenton's reagent

Fenton's reagent is a mixture of ferrous sulphate & hydrogen peroxide.

Give the other name for aniline

Phenylamine C₆H₅NH₂

Monday, September 27, 2010

Difference between aniline & ethyl amine

Aniline is a colorless oily liquid but ethyl amine is a colorless gas which can be easily liquefied.
Aniline undergoes sulphonation, nitration & bromination but ethyl amine does not give such reactions.
With bromination aniline forms a white precipitate but ethyl amine does not give such reactions.
With benzaldehyde aniline forms schiff's base. But there is no such action for ethyl amine.
With benzene diazonium chloride, aniline gives p-amino benzene.But ethyl amine does not give such reactions.
Aniline is easily oxidised, but ethyl amine is not easily oxidised.
Aniline has an unpleasant odour but ethyl amine has a fishy ammoniacal odour.
Aniline is insoluble in water but ethyl amine is readily soluble in water.

Why HCOOH reduces tollens reagent?

Tollens reagent is ammoniacal silver nitrate solution. HCOOH is formic acid. As we all know it has an aldehyde group in its structure. So it is able to reduce tollens reagent.

Phenol is acidic but doesnot react with NaHCO₃. why?

Phenol does not react with NaHCO₃ because it is weaker than carbonic acid.

Why tertiary amines are not acetylated?

This is because tertiary amines do not have H atom attached to nitrogen.

Chemically Rochelle salt is

Potassium sodiumtartrate. It is important to note that Rochelle salt is used in the preparation of fehling's solution.

Do you know the reason why a small amount of alcohol is added to the chloroform bottles?

This is because alcohol retards the oxidation of chloroform to phosgene & it converts any phogene or carbonyl chloride formed to ethyl carbonate. It is important to note that ethyl carbonate is harmless.

Why chloroform is stored in dark colored bottles?

This is an important question. I hope every chemistry students are familiar with this. The reason is very simple. Chloroform in the presence of air gets oxidised to phosgene. Phosgene is carbonyl chloride & is represented as COCl₂. To prevent the formation of phosgene, chloroform is stored in dark colored bottles.
This is represented as CHCl₃ + 1/2 O₂---->COCl₂ + HCl.

Thursday, September 16, 2010

How benzoin is formed from benzaldehyde?

On warming benzaldehyde with aqueous alcoholic KCN, benzoin is formed. This reaction is also known as benzoin condensation.
2C₆H₅CHO-----> C₆H₅CH(OH)COC₆H₅.

Benedict's solution

Do you know what is benedict's solution? This is an alkaline solution of a complex copper citrate. In reaction with aldehyde this function in the same way as that of fehlings solution. The importance of fehling's solution is discussed in my other blog, chemistry experiments.