Rates of reaction between hydrochloric acid and sodium sulphate

The rate of a chemical reaction is the amount of reactant used up, or product made, in a given time. Do not use the words 'speed' or 'how fast'. The rate of a reaction can be measured in one of two general ways.

Here the reaction is started and timed until it is finished. Each experiment produces one reading. No readings are taken during the reaction.

e.g. Reaction between sodium thiosulphate and dilute acid:

Na2S2O3(aq) + 2HCl(aq) --> S(s) + SO2(g) + 2NaCl(aq) + H2O(l)

Here the reaction is started and timed until it is finished. Each experiment produces one reading. No readings are taken during the reaction.

e.g. Reaction between sodiu...