Analyse data and graphical representations of relative changes in the concentration, volume and mass against time to determine rate of reaction. (Order of reaction is not required.)

A student investigated the decomposition of hydrogen peroxide \((\text{H}_2\text{O}_2)\) using the catalysed reaction: \[2\text{H}_2\text{O}_2(\text{aq}) \rightarrow 2\text{H}_2\text{O}(\text{l}) + \text{O}_2(\text{g})\] The student measured the volume of oxygen gas produced at regular time intervals. The results are shown in the table below. Analyse the data to determine the average rate of oxygen production between \(30\) s and \(90\) s, expressed in \(\text{cm}^3\,\text{s}^{-1}\).

A student investigates the reaction between magnesium ribbon and hydrochloric acid by measuring the total volume of hydrogen gas produced over time. The data collected are shown in the table below. Analyse the data to determine the average rate of reaction between \(t = 20\) s and \(t = 50\) s.