A student investigated the rate of reaction between magnesium ribbon and dilute hydrochloric acid. The volume of hydrogen gas was measured at regular intervals.
The table below shows the results of the investigation:
Time (s)Volume of hydrogen gas collected (cm3)002018403260428048100521205414054\begin{array}{|c|c|} \hline \text{Time (s)} & \text{Volume of hydrogen gas collected (cm}^3\text{)} \\ \hline 0 & 0 \\ \hline 20 & 18 \\ \hline 40 & 32 \\ \hline 60 & 42 \\ \hline 80 & 48 \\ \hline 100 & 52 \\ \hline 120 & 54 \\ \hline 140 & 54 \\ \hline \end{array}Time (s)020406080100120140Volume of hydrogen gas collected (cm3)018324248525454
Calculate the mean rate of reaction between 0 seconds0\text{ seconds}0 seconds and 80 seconds80\text{ seconds}80 seconds.
Use the equation: mean rate of reaction=volume of gas formedtime taken\text{mean rate of reaction} = \frac{\text{volume of gas formed}}{\text{time taken}}mean rate of reaction=time takenvolume of gas formed
State the value and choose the correct unit from: cm3/s\text{cm}^3\text{/s}cm3/s, g/s\text{g/s}g/s, s/cm3\text{s/cm}^3s/cm3, or s/g\text{s/g}s/g.