A description that makes reference to the following points:
- test for propanal/aldehyde: Benedict's or Fehling's solution, or ammoniacal silver nitrate / Tollens' reagent (1)
- result for propanal: red precipitate, or silver mirror with Tollens' reagent (1)
- test for propanoic acid: addition of carbonate / hydrogencarbonate solution, reactive metal, or a named alcohol and acid catalyst (1)
- result for propanoic acid: effervescence/fizz of carbon dioxide which turns limewater cloudy; or hydrogen that pops with a lighted splint; or a sweet/fruity-smelling ester (1)
Additional guidance:
- Do not award acidified potassium dichromate(VI) for propanal
- Ignore addition of PClX5 gives misty fumes
- Ignore reference to indicators
- If candidates omit names of compounds, assume the tests are for the correct compounds