A Levels Chemistry

Solid calcium carbonate is added to 100 cm3 of dilute hydrochloric acid and the rate of the
reaction is measured. 100 cm³ of distilled water is then added to a second 100 cm portion of the
acid, and the experiment repeated under the same conditions.
Why does the addition of water decrease the rate of the reaction?
1
Adding water reduces the frequency of collisions between reactant molecules.
2 Adding water reduces the proportion of effective collisions between reactant molecules.
3 Adding water reduces the proportion of reactant molecules possessing the activation energy.


Reaction Kinetics | 2011 - M/J - 9701/12 | Q31