Hard Practice — Advanced Set

Hard Practice — Combined Identification & Titration

Chain the evidence: use two or more tests together (flame colour + precipitate, or functional-group tests) to identify a salt or compound, and carry titration stoichiometry ($N_1V_1=N_2V_2$ or mole ratios) through to purity/percentage.

• $KMnO_4$ (n = 5, acidic), oxalic acid (n = 2), $K_2Cr_2O_7$ (n = 6); $\%$ purity from the titre.
• Tests: aldehyde (Tollens'/Fehling'), $CH_3CO$- (iodoform), acid ($NaHCO_3$), phenol ($FeCl_3$).