A student investigated the rate of the reaction between magnesium ribbon and dilute hydrochloric acid. Hydrogen gas was produced and collected in a gas syringe.
The student measured the time taken to collect 30 cm3 of gas. The table below shows the calculated rates of reaction for each of the four trials.
| Trial | Rate of reaction in cm3/s\text{cm}^3/\text{s}cm3/s |
|---|---|
| Trial 1 | 0.74 |
| Trial 2 | 0.35 |
| Trial 3 | 0.77 |
| Trial 4 | 0.74 |
Determine the mean time taken to collect 30 cm3 of gas. Do not include any anomalous results in your calculation.
Use the equation:
mean rate of reaction=volume of gas collectedmean time taken \text{mean rate of reaction} = \frac{\text{volume of gas collected}}{\text{mean time taken}} mean rate of reaction=mean time takenvolume of gas collected26 exam-style questions on AQA GCSE Chemistry 6.1 Rate of reaction, covering 6.1.1 Calculating rates of reactions, 6.1.2 Factors which affect the rates of chemical reactions, 6.1.3 Collision theory and activation energy, and 6.1.4 Catalysts. Each one has a worked solution and a mark scheme showing where the marks go.