Salt Bridge on Electrified Waters “Chemistry is the study of substances; their properties, their structure and the changes they undergo” (bottom). Chemistry is the study of all things in the world and especially how they change. My experience mainly focuses on changing substances. Some of the concepts involved in my experiment are oxidation/reduction (redox) reactions, electrolysis, pH, and electric currents. A redox reaction is a reaction in which there is a transfer of electrons from one substance to another. A redox reaction has two paired parts: oxidation and reduction. Oxidation is the loss of electrons while reduction is the gain of electrons. They always occur together because a substance must receive