Chapter 5 Surface Chemistry Chemistry class 12 Chapter 5 Surface Chemistry, Class 12 | Page 8

8 . In chromatographic analysis . 9 . Qualitative analysis , e . g ., lake test for Al 3 +.
Catalysis
Catalyst is a chemical substance which can change the rate of reaction without being used up in that reaction and this process is known as catalysis
A catalyst may be positive ( i . e ., increases rate of reaction ) or negative ( i . e ., decreases rate of reaction ).
Types of Catalysis
Homogeneous catalysis In this catalysis , and the catalyst reactants are in the same physical state [ phase ], e . g .,
Heterogeneous catalysis In heterogeneous catalysis , catalyst is present in a different phase than that of reactants , e . g .,
Autocatalysis When one of the product of a reaction acts as catalyst , the process is called autocatalysis .