__________________________________________________________________________ 2 marks Total 8 marks Question 2 The reaction between bromine gas and methanoic acid is Br2(aq) + HCOOH(aq) 2Br-(aq) + 2H+(aq) + CO2(g) Br2 gas has a brown colour but Br- ions are colourless. a. A 1.0 mole sample of bromine is reacted with a 0.8 mole sample of methanoic acid. i. Describe the likely change in brown intensity an observer will see. ________________________________________________________________________ The reaction is repeated with the same amount of chemicals but this time with an added ii. catalyst. Compare the change in brown intensity of this reaction with the first reaction. __________________________________________________________________________ 1 + 1 = 2 marks b. i. The reaction is repeated in a flask that is sitting on a balance. Draw in the shape of the graph for the mass change of the flask. mass of flask time ii. Calculate the final mass loss of the flask.
__________________________________________________________________________ 2 marks Total 8 marks Question 2 The reaction between bromine gas and methanoic acid is Br2(aq) + HCOOH(aq) 2Br-(aq) + 2H+(aq) + CO2(g) Br2 gas has a brown colour but Br- ions are colourless. a. A 1.0 mole sample of bromine is reacted with a 0.8 mole sample of methanoic acid. i. Describe the likely change in brown intensity an observer will see. ________________________________________________________________________ ii. The reaction is repeated with the same amount of chemicals but this time with an added catalyst. Compare the change in brown intensity of this reaction with the first reaction. __________________________________________________________________________ 1 + 1 = 2 marks b. i. The reaction is repeated in a flask that is sitting on a balance. Draw in the shape of the graph for the mass change of the flask. mass of flask time ii. Calculate the final mass loss of the flask.
rates_and_reversible_reactions__test.docx