Factors affecting rateIB MYP Chemistry: Mind map

Exam questions on Factors affecting rate

1. A student in Lima reacts 1.0 g of zinc granules with 50 cm³ of excess dilute hydrochloric acid and measures the volume of hydrogen made over time. She then repeats the experiment with 1.0 g of zinc powder, keeping everything else the same.
   Explain why zinc powder reacts faster than zinc granules.2 marks
2. Ammonia for fertiliser is made in the Haber process, in which nitrogen gas reacts with hydrogen gas at high temperature and high pressure in the presence of an iron catalyst. Engineers at the plant are always looking for ways to make ammonia faster.
   State two ways, other than adding a catalyst, of increasing the rate of the reaction between nitrogen and hydrogen.2 marks
3. An engineer in Seoul tests an effervescent tablet that fizzes when it is dropped into 200 cm³ of water. She times how long the tablet takes to stop fizzing at three temperatures. At 15 °C it takes 120 s, at 25 °C it takes 60 s and at 35 °C it takes 30 s.
   Describe the effect of temperature on the rate of reaction, using the data to support your answer.3 marks