In these two classroom demonstrations, students observe the reaction between H[subscript 2] gas and Pd foil. In the first demonstration, hydrogen and palladium combine within one minute at 1 atm and room temperature to yield the non-stoichiometric, interstitial hydride with formula close to the maximum known value, PdH[subscript 0.7]. In the process, palladium undergoes a noticeable color change and increase in brittleness. In the second classroom demonstration, the kinetics of H[subscript 2] uptake is determined and yields a zero-order rate law. Other observations are provided to guide students to conclude that the experimental conditions for the demonstration result in kinetics governed by H[subscript 2] mass transport. Both classroom demonstrations use the same simple apparatus, but otherwise are mutually independent. (Contains 4 figures and 7 notes.)