Answers Sample Answers and Mark Allocation Notes (c)i Not acceptable: Indicator/named acid/base indicator Ferroxyl indicator pH/universal indicator 1 Bicarbonate indicator (d) mole ratio 0.002 : 0.004 1 mark 0.004 on its own 1 mark Marks St Gr Another experiment involved determining the concentration of sodium carbonate solution by 2013 titration. Q 18 (b) ii The results showed that 20 cm3 of sulphuric acid was required to neutralise the sodium carbonate solution. One mole of sulphuric acid reacts with one mole of sodium carbonate. 0.001 moles of sulphuric acid reacted, calculate the concentration, in mol/l, of the sodium carbonate solution. Question Sample Answers and Mark Allocation Notes
Answers Sample Answers and Mark Allocation Notes (c)i Indicator/named acid/base indicator pH/universal indicator 1 Not acceptable: Ferroxyl indicator Bicarbonate indicator (d) mole ratio 0.002 : 0.004 1 mark 0.004 on its own 1 mark Marks St Gr 2013 Q 18 (b) ii Another experiment involved determining the concentration of sodium carbonate solution by titration. The results showed that 20 cm3 of sulphuric acid was required to neutralise the sodium carbonate solution. One mole of sulphuric acid reacts with one mole of sodium carbonate. 0.001 moles of sulphuric acid reacted, calculate the concentration, in mol/l, of the sodium carbonate solution. Question Sample Answers and Mark Allocation Notes