Write one difference in each of the following :
Homogeneous catalysis and Heterogeneous catalysis
Homogeneous catalysis: When the reactants and the catalyst are in same phase (i.e., Liquid or gas), the process is said to be homogeneous catalysis. For example, Oxidation of sulphur dioxide into sulphur trioxide with dioxygen in presence of oxides of nitrogen as the catalyst in the process.
2SO2(g) + O2(g)→ NO(g) +2SO3(g)
Heterogeneous catalysis: The catalytic process in which the reactant and the catalyst are in different phase is known as heterogeneous.For example Oxidation of sulphur dioxide into sulphur trioxide in the presence of Pt.
2SO2(g) + pt(s)→ 2SO3 (g)
Define the following terms:
i)Lyophilic colloid
ii) Zeta potential
iii) Associated colloids
(i) Differentiate between adsorbtion and absorption.
(ii)Out of MgCl2 and AlCl3, which one is more effective in causing coagulation of negatively charged sol and why?
(iii)Out of sulphur sol and proteins, which one form multimolecular colloids?
Classify colloids where the dispersion medium is water. State their characteristics and write an example of each of these classes.
OR
Explain what is observed when
(i) An electric current is passed through a sol
(ii) A beam of light is passed through a sol
(iii) An electrolyte (say NaCl) is added to ferric hydroxide sol
