PP Presentation
GAS FORMING REACTIONS
- some reactions generate gases. When carried out in an OPEN system,
the escape of the gas acts as a DRIVING FORCE for the chemical reaction
- loss of gas product pulls reaction to completion just as formation of
a precipitate
e.g.
CaCO3 (s) + 3 HCl (aq) ® CaCl2 (aq) + H2O (l) + CO2 (g)
Zn (s) + 2 HCl (aq) ® ZnCl2 (aq) + H2 (g)
NB. Each of these reactions can also be classified as one of the other
3 types of reactions - WHICH ONES ?