Stpm Chemistry Experiment 10 201314 [top] -

The core of the experiment is mastering the —specifically condensation reactions with derivatives and oxidation reactions.

: For aluminate complexes, the product is typically white or colorless crystals; for iron complexes, it may range from pale green to violet.

For the reaction: [ mM^n+ + lL \rightarrow [M_m L_l]^x+ ] The maximum absorbance occurs at the mole fraction corresponding to the stoichiometric ratio ( m : l ). Stpm Chemistry Experiment 10 201314

cap C u cap S cap O sub 4 center dot 5 cap H sub 2 cap O open paren s close paren plus 4 cap N cap H sub 3 open paren a q close paren right arrow open bracket cap C u open paren cap N cap H sub 3 close paren sub 4 close bracket cap S cap O sub 4 center dot cap H sub 2 cap O open paren s close paren plus 4 cap H sub 2 cap O open paren l close paren 3. Materials and Apparatus

: Incomplete reaction, loss of product during filtration, or moisture retention during weighing. The core of the experiment is mastering the

Salicylate (C₆H₄(OH)COO⁻) forms a deep violet complex with Fe³⁺. The intensity of the colour is proportional to the concentration of the complex, making spectrophotometry ideal.

Since the ratio is 1:1, Moles of Product = Moles of Reactant. Theoretical Mass = Percentage Yield Percentage Yield Actual Mass obtained Theoretical Mass cap C u cap S cap O sub

: A violet color indicates the presence of unreacted salicylic acid (phenol group).

From actual examiner reports of that period: