which of the following reations are examples for heterogeneous catalysis ?
A. `2H_(2)O_(2)(l)overset(MnO_(2)(s))to2H_(2)O(l)+O_(2)(g)`
B. `2SO_(2)(g)+ O_(2)(g)overset(NO(g))to 2SO_(3)(g)`
C. `2SO_(2)(g)+ O_(2)(g)overset(NO(g))to 2SO_(3)(g)`
D. `CH_(3)COOC_(2)H_(5)(aq)+H_(2)O(l)overset(HCl(aq))toCH_(3)COOH(aq.)+ C_(2)H_(5)OH(aq.)`
