search

Hinsberg Test for Amine


Distinction between primary, secondary and tertiary amine Using Hinsberg  reagent


Three classes of amines are distinguished by Hinsberg reagent test. The Hinsberg reagent is benzene sulphonyl chloride (C6H5SO2Cl).


1. Reaction of Hinsberg reagent with Primary amine

A primary amine forms a precipitate of N-alkyl benzene sulphonamide with Hinsberg reagent. This precipitate is soluble in alkali.

RNH2 (primary amine)  +  C6H5SO2Cl (Hinsberg reagent) ------------>  R-NH-SO2-C6H5  ------(NaOH)---> R-N-Na+-SO2C6H5 (soluble)



2. Reaction of Hinsberg reagent with secondary amine

 Secondary amine reacts with Hinsberg reagent to form a precipitate N,N-dialkyl benzene sulphonamide. But this precipitate is insoluble in alkali.


R2NH (secondary amine)  +  C6H5SO2Cl (Hinsberg reagent) ------------> R2NSO2C6H5 (precipitate)  -----(NaOH)---> insoluble (no reaction)



2. Reaction of Hinsberg reagent with Tertiary amine


Tertiary amines do not react with Hinsberg reagent,


R3N (Tertiary amine)  +  C6H5SO2Cl (Hinsberg reagent) ------------>No reaction



Hinsberg reagent can also be used for the separation of primary, secondary and tertiary amine from a mixture.

General Knowledge Questions: Chemistry


GK Chemistry Questions and answer about Elements

Some frequently asked Chemistry gk questions about elements


Chemistry GK >> 1. Hydrogen


1. Which is the most abundant element in the Universe ?
Answer: Hydrogen


2. Which is the atom without Neutron ?
Answer: Hydrogen


3. Who discovered Hydrogen ?
Answer: Henry Cavendish


4. Who named Hydrogen ?
Answer: Lavoisier

5. Which isotope of Hydrogen has Radio Active nature ?
Answer: Tritium


6. Which gas is used to make Vanaspathi ?
Answer: Hydrogen


7. Which is the lightest element ?
Answer: Hydrogen


8. Which is the element common to all Acid ?
Answer: Hydrogen


Chemistry GK >> 2. Helium 


1. Which is the second most abundant element in the universe ?
Answer: Helium


2. Which gas is used to for filling air ships and observation balloons ?
Answer: Helium


3. Who discovered Helium ?
Answer: William Ramsay


4. Which is the lightest Noble gas ?
Answer:  Helium



* Chemistry GK >> 3. Lithium


1. Which metal has least density ?
Answer: Lithium


2. Which metal is kept in wax ?
Answer: Lithium



* Chemistry GK >> 4. Carbon


1. Who discovered Carbon dioxide ?
Answer: Joseph black


2. Who discovered Carbon Monoxide ?
Answer: Joseph Priestly


3. Solid form of Carbon dioxide is known as ?
Answer: Dry Ice


4. What is water gas ?
Answer: Mixture of carbon monoxide and hydrogen


5. What is Producer gas ?
Answer:  Mixture of carbon monoxide and Nitrogen


* newly updated
General knowledge chemistry Questions about more element will be added soon..


Visit to get 10 Important Chemistry gk questions

 For possible chemistry gk questions visit Chemical name and GK questions


 If you know more questions about those element please add it as comment, help others.

Application of Adsorption


Industrial Application of Adsorption Process



1. Activated charcoal is used to remove bad odours inside refrigerator and to deodourise tap water in water purifier. It is also used in gas masks to adsorb poisonous gases in the atmosphere.

2. In sugar industry animal charcoal is used to decolourise raw sugar solution obtained from sugar cane.

3. In chromatography, suitable adsorbents are used. They selectively adsorb certain substance from solution. Adsorption chromatography is used for detection and separation of mixtures.

4. In dehumidifier, silica gel is used as adsorbent.

5. Activated charcoal is  used to maintain vacuum in laboratory vessels such as Dewar flask.

6. Heterogeneous catalysis  mostly operate through adsorption of reactant molecules.

7. Softening of water using ion exchange resin is based on selective adsorption of ions which cause hardness.

8. In mordant dyeing, mordants adsorb colour.

9. Ferric hydroxide can adsorb arsenic ions and hence it is used as antidote against arsenic poisoning.

Adsorption Isobar


Adsorption Isobar : Effect of temperature


Most of the adsorptions are exothermic reactions, Hence adsorption generally depend on temperature. Exothermic reactions are mostly spontaneous at low temperature. Hence the extent of adsorption decreases with increase of temperature at constant pressure. A plot of extent of adsorption verses temperature at constant pressure is known as adsorption Isobar.

Factors affecting adsorption


Factors affecting adsorption: Pressure of Gas


Adsorption and desorption are reversible process and take place simultaneously leading to equilibrium state.

Adsorbent + gas  <========> Adsorbent gas


In the forward direction, during adsorption, volume decreases since gases are adsorbed to the surface. Hence applying Le-Chatelier principle, we can predict effect of pressure. At high pressure, the system has a tendency to decrease volume and shifts towards forward direction, ie , more adsorption take place. Now we can conclude that extent of adsorption (x/m) increases with increase in pressure. Where x= number of the moles of gas adsorbed and m = mass of adsorbent, at equilibrium. Variation of  x/m with pressure can be experimentally studied and can be plotted as a graph at constant temperature. Such graphs obtained by plotting (x/m) against (p) at constant temperature are called, adsorption isotherm.


To see all Factors affecting adsorption of gases on solids visit http://entrancechemistry.blogspot.com/2012/11/factors-affecting-adsorption-of-gases.html