Question

Animal charcoal is used in decolourising colour of liquids because it is a good:
A. Adsorbate
B. Adsorbent
C. Oxidising agent
D. Reducing agent

Answer 1

Hint: When the carbon is diffused in a very finely divided state and consequently presents a very large surface area it possesses some adsorptive properties. Animal charcoal is highly porous and has good adsorptive power.

Complete step-by-step answer:
Animal charcoal is obtained from blood, horn, bones, etc. by the process of destructive distillation. It has some special characteristics. It has power to remove substances from a solution. It decolourises the brown solution of raw sugar when boiled together. Some more examples are indigo, iodine, litmus, red-wine colouring agent, astringent principles, and fused oil from alcohol can be easily removed by using animal charcoal.
It has a big role in water filtering and for purifying organic compounds in laboratories by removing tarry matter that usually forms in them.it is also employed for purifying paraffin wax and glycerine, also to remove dust from ivory black. When the charcoal powder is exhausted, it can be renewed by treatment with reagents or ignition.
All these things tell us about adsorption taking place in this phenomenon, which includes fixation of substances in solution and gases. Colloidal substances or substances with large molecular weights are the ones that get absorbed from solution by alcohol. Animal charcoal owes its decolourising action in organic compounds which are stable at red heat.
There were many conclusions drawn on the process of adsorption of iodine by charcoal, done by Freundlich as per theory of adsorption. These are:
Adsorption of iodine by charcoal consists of a surface condensation and a diffusion into the bulk of the carbon. Surface condensation is rapid but diffusion continues for weeks or months, therefore we can say that surface condensation is independent of diffusion. Sugar and animal carbons possess the same power of adsorption and so are good adsorbates. The amount of adsorption is specific and depends on the nature of both the solvent i.e. adsorbent and the adsorbing substance (adsorbate).

Hence, the correct option is (A).

Note: Animal charcoal has only \[10\% \] carbon content, rest are inorganic materials. That’s why its decolorizing power is not permanent and gets lost after using it for some time, like it may be revived by reheating or washing. But it is more effective than wood charcoal.