Which reaction involves one substance losing an electron while another gains it, leading to oxidation and reduction?

The reaction that involves one substance losing electrons while another substance gains them is known as a redox reaction, which stands for reduction-oxidation. In this type of reaction, the substance that loses electrons undergoes oxidation, while the substance that gains electrons is reduced. This transfer of electrons is fundamental to many biological processes, including cellular respiration and photosynthesis.

In contrast, hydrolysis reactions involve the breaking of bonds through the addition of water, often leading to the cleavage of polymers into monomers but do not involve electron transfer. Dehydration synthesis is the process where molecules are joined together by the removal of water, forming bonds rather than transferring electrons. Electrolysis involves the decomposition of compounds through the use of electricity, but it is not defined specifically as a redox process in the broader sense—while it can involve redox reactions, it is more focused on the use of electrical energy for chemical change rather than the exchange of electrons between substances.

Therefore, redox reactions specifically encapsulate the concept of electron transfer, highlighting the processes of oxidation and reduction occurring simultaneously.