The newest 11 of 11 written questions. Open one to see it on the real paper.
Which other pieces of apparatus are used to find the rate of reaction?
See it on the paper →Calculate the rate of reaction between solid H and dilute sulfuric acid. Use the equation shown. rate of reaction = mass of solid H reaction time Give your answer to two significant figures. rate of reaction = g / s
See it on the paper →Suggest one reason why it is difficult to measure the reaction time accurately using this procedure.
See it on the paper →Suggest one improvement to the procedure that improves confidence in the rate of reaction calculated. Explain your answer. improvement explanation
See it on the paper →Explain why it is important to stir the reaction mixture.
See it on the paper →Describe the relationship between mass of sodium carbonate and reaction time.
See it on the paper →Suggest why the student is not able to collect all the gas made in the first 20 seconds.
See it on the paper →Suggest one piece of apparatus that is not shown in Fig. 8.1 which the student needs to investigate the rate of this reaction.
See it on the paper →Suggest one improvement to this experiment to make the results more accurate.
See it on the paper →Suggest how the experiment could be changed so that the highest temperatures reached can be compared more reliably. Do not include repeating the experiment.
See it on the paper →Suggest what might have happened for the student to get an anomalous temperature reading.
See it on the paper →Many candidates used the equation provided and gave their answer to two significant figures. A common mistake was to record to only one significant figure.
— Examiner report, October/November 2023, 0653/63 Q3(d)(iv) (Cambridge)
This was a demanding question with most candidates suggesting human error when using a stopwatch as the reason it was difficult to measure the reaction time. With reference to step 5 of the method, stronger responses stated that it was difficult to judge when the reaction, or fizzing, had ended.
— Examiner report, October/November 2023, 0653/63 Q3(d)(v) (Cambridge)
Many candidates simply stated ‘repeat’ as a way to improve the procedure. Very few went on to explain how this would improve confidence in the rate of reaction. Stronger responses described how a repeat would allow for identifying anomalous results, or that repeating and averaging would reduce the effect of random errors.
— Examiner report, October/November 2023, 0653/63 Q3(d)(vi) (Cambridge)
Past papers, syllabus and examiner reports © UCLES (Cambridge University Press & Assessment). Questions are matched to topics from the official syllabus. AssessPro is independent and not endorsed by Cambridge.