(a) Which will adsorb more gas, a lump of charcoal or its powder and why?
(b) Describe the preparation of the following colloidal solutions. Name the method used in each case:
(i) Silver sol (ii) Sulphur sol

What are the characteristics of the following colloids ? Give one example of each (i) Multimolecular colloids (ii) Lyophobic sol (iii) Emulsions.

Define the following terms with an example in each case: (i) Macromolecular sol (ii) Peptization (iii) Emulsion

Which of the following methods is (are) used to prepare colloidal sols?

What is meant by coagulation of a colloidal solution? Name any method by which coagulation of lyophobic sols can be carried out.

(a) Make a clearly labelled diagram of the inner ear of a human being. (b) Describe how each of the following is achieved in us (i) hearing (ii) balance

What is meant by coagulation of a colloidal solution ? Describe briefly any three methods by which coagulation of a lyophobic sol can be carried out.

Define the following terms giving an example of each: (i) Associated colloids (ii) Lyophilic sol (iii) Adsorption

(i) Why could fluorine not be prepared for a long time from HF and metal fluorides either by electrolysis or by any chemical reaction ? (ii) Describe the modern method for the preparation of fluorine by giving: (a) Materials used in the construction of the cell. (b) Electrolyte used. (c) Electrode reactions.

(a) Name the reagents and write the chemical equations for the preparation of the following compounds by Williamson's synthesis : (i) Ethoxybenzene (ii) 2-Methyl-2-methoxpyropane (b)Why do phenols not give the protonation reaction readily?

Collidal dispersion have been classified into different types depending upon the physical state of the dispersed phases and the dispersion medium. They are prepared in the industry or in the laboratory by a number of methods and then purified. The protective action of lyophilic colloids was studied by Zsigmondy and he introduced a term called gold number. Which of the following will have maximum flocculation value for aresnic sulphide sol?