Which of the following is a very fast reaction ?

Options

A. `Fe(s)overset(O_(2)//H_(2)O)rarr Fe_(2)O_(3) . XH_(2)O`
B. `Na_(2)SO_(4)(aq.)+BaCI_(2)(aq.)rarrBaSP_(4)(S)+2NaCI(aq.)`
C. `C_(12)H_(22)O_(11)+H_(2)O overset(H^(+))rarrC_(6)H_(12)O_(6)+C_(6)H_(12)O_(6)`
D. `NH_(4)NO_(2)overset(Delta)rarr2H_(2)O+N_(2)`

Answer

B

Explanation

The larger the area of contact, the faster the reaction. Thus finely divided catalysts are more effetive, liquid bromine reacts slowly as compared to bromine vapor and a lump of coal burns at a moderate rate in air while coal dust burns explosively.