1. Investigation factors affecting the reaction rate: Reaction of marble chips with
hydrochloric acid.
Several factors can influence the chemical reaction rate. These factors are concentration,
temperature, pressure (gaseous state), light, surface area, nature of the reactants, and
catalyst.
Method 1:
Experiment 1: 10 ml of acid was added to a boiling tube contain small marble chips.
Experiment 2: 10 ml of acid was added to another boiling tube containing large marble chips.
In both experiments the total mass of the marble chips was the same and the
concentration of the acid is the same. The boiling tubes were connected to an inverted
measuring cylinder in a basin of water, as shown in the diagram below.

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