Nanobubbles (NBs) are tiny gas cavities with diameters around 200 nm that remain stable in solution due to their unique properties, including low buoyancy and negative surface charges. Ammonium ...

Commercial heat packs (containing iron and water, or supersaturated sodium acetate) and cold packs (various ammonium salts) can be used to show exo- and endothermicity. Heat packs that contain iron ...