GCSE COMBINED SCIENCE: TRILOGY Higher Tier Chemistry Paper 2H

This question is about the Earth’s resources. When most fuels burn carbon dioxide is produced. Propane (C3H8) is a fuel. Balance the equation for the combustion of propane. [1 mark] C3H8 + O2 → 3 CO2 + 4 H2O Describe the test for carbon dioxide. Give the result of the test. [2 marks] Test Result Propane can be cracked to produce propene and hydrogen. Complete the symbol equation for the reaction. [1 mark] C3H8 → + H2 propane propene hydrogen Do not write outside the box 3 *03* Turn over ► IB/M/Jun20/8464/C/2H Do not write outside the box Describe the test for hydrogen. Give the result of the test. [2 marks] Test Result Propene is an alkene. Describe the test for alkenes. Give the colour change in the test. [3 marks] Test Colour change to Turn over for the next question 4 *04* IB/M/Jun20/8464/C/2H Do not write outside the box 0 2 Some students investigated the effect of temperature on the rate of reaction. The students reacted sodium thiosulfate solution with hydrochloric acid. This is the method used. 1. Use a beaker to measure 50 cm3 of heated sodium thiosulfate solution into a conical flask. 2. Measure the temperature of the room. 3. Put the conical flask on a black cross drawn on a piece of paper. 4. Start a timer. 5. Use the same beaker to measure 10 cm3 of hydrochloric acid into the conical flask. 6. Stop the timer when the cross is no longer visible. The students repeated the experiment at a different room temperature.