In this brief experiment, students create a superhydrophobic surface as an application of polar–nonpolar interactions and redox chemistry. Half of a zinc-galvanized steel strip is coated in copper nanoparticles through electroless deposition. A layer of nonpolar octadecanethiol is added to half of that copper surface. Students classify the three resulting surfaces as polar or nonpolar using water drops as a probe. This simple procedure illustrates introductory chemical concepts while incorporating nanochemistry and illustrating surfaces of increasing technological importance.

Chemical energy storage and use is a critical part of a sustainable world. In this laboratory experiment, students construct and use an inexpensive hydrogen fuel cell to power a calculator or a clock. The reusable cells are prepared from plastic syringes and a nickel mesh that is coated with a palladium metal catalyst by electroless deposition. One syringe is filled with hydrogen gas and the other with air. A sodium hydroxide solution is the bridge between the cells. Students measure the produced voltage and combine two fuel cells to power electronics requiring 1.5 V. The goal is for students to make the connection between theory and practice for symbolic representations of redox reactions and their macroscopic and atomic/molecular interpretations.

For solid solutions with the same arrangement of atoms, the size of a unit cell depends on the size of the atoms in the unit cell. The distance between nuclei also helps determine how strongly electrons are held, which changes the band gap energy. Samples of semiconductor CH 3 NH 3 Pb(I 1−x Br x ) 3 solid solutions were prepared; the unit cell size was measured by powder X-ray diffraction, and the band gap energy was measured by visible absorption spectroscopy. This use of a material with significant research and technological implications for solar cells illustrates the periodic properties relationship between composition, atomic size, and electron energy levels.

Ion-selective electrodes are among the oldest and most important potentiometric sensing methods. In this experiment, students assemble their own reusable ion-selective electrode from glass tubes with an attached PTFE membrane, [(CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 ) 3 NCH 3 ]X ion exchanger, and both internal and external Ag/AgCl reference electrodes. Students then evaluate the electrode response as a function of specific-ion activity, measure the activity of an unknown-concentration solution, and determine the electrode selectivity by repeating the analysis in the presence of a fixed amount of interfering ion. With a choice of chloride, nitrate, acetate, and sulfate specific-ion electrodes and a variety of interfering ions, each student in a lab section can do a different experiment while keeping both the lab cost for consumables and the setup time low. The obtained selectivity values are in agreement with the Hofmeister series. Students practice analytical laboratory skills by designing and preparing a calibration curve, see benefits and limitations of ion-selective electrodes, and make use of the Nernst equation.

Polymers and nanochemistry are important facets of chemistry. In this experiment, students synthesize monodispersed poly­(methyl methacrylate) nanospheres from the addition or chain polymerization of a rapidly stirred aqueous mini-emulsion of methyl methacrylate. The 2,2′-azobis­(2-methylpropion­amidine) dihydrochloride serves as a heat activated, water-soluble, free radical initiator to polymerize the emulsion droplets starting from their outer edge. The uniform small diameter particles will appear iridescent if they are close-packed and their size is similar to the wavelength of visible light. Students characterize the size of the poly­(methyl methacrylate) spheres by four methods: the settling velocity and Stokes’ law, evaporative self-assembly of a photonic material and visible spectroscopy, direct measurement using scanning electron microscopy (SEM), and SEM measurement of the silica inverse opal. This experiment increases student collaboration and provides the opportunity to work on multiple experiments at once.