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This work is focused on the optimization of the synthesis conditions of a Pt sol phase containing suspended metallic Pt nanoparticles with the primary goal being to produce thin (ca. 1 monolayer) Pt films having the highest possible electroactive surface area per gram. This is gauged here by the surface roughness factor, determined from the magnitude of the Pt electrochemical response in sulfuric acid solution. Two Pt(IV) chloride compounds (H 2 PtCl 6 , Na 2 PtCl 6 ) are shown to be the best Pt precursors, producing stable Pt nanoparticles with an average particle diameter of 1-3 nm. Sodium ethoxide and formic acid are found to be excellent reducing agents of the PtCl 6 2-anion, although formaldehyde results in a lower yield of Pt nanoparticles. A ratio of sodium ethoxide to H 2 PtCl 6 of 2:1 and a 72°C reflux in ethanol between 30 min and 5 h resulted in the highest Pt roughness factor (ca. 8). Transmission electron microscopy analysis has verified that all of the reducing agents produce Pt particles of a similar size and that the higher roughness factors are the result of a higher yield of Pt nanoparticles. The effect of time of storage of Pt sols formed using sodium ethoxide showed that only a minor aging effect is observed over long periods of time, likely minimized by the stabilization offered by PtCl 3 (C 2 H 4 ) -, a species formed as a byproduct during the synthesis.

Salicylic acid and its derivative, acetylsalicylic acid, are often encountered in introductory organic chemistry experiments, and mention is often made that salicylic acid was originally isolated from the bark of the willow tree. This biological connection, however, is typically not further pursued, leaving students with an impression that biology and chemistry are separate entities in the laboratory. We have developed a laboratory that investigates this biological connection in which salicylic acid is extracted from willow bark and detected using thin-layer chromatography. This experiment can be adopted as either a standalone experiment or integrated into other laboratory courses with current experiments involving salicylic acid.