What reaction forms the basis of many of today's conveinences such as fuel, bleaches, batteries, and photos?

Answer 1

Oxidation-reduction reactions.

Fuel (carbon-based) is oxidized to CO2 and H2O.

Bleaches (like Clorox, NaOCl) oxidize colored substances to colorless ("white") ones, while the bleach is reduced to NaCl.

In batteries, oxidation occurs inside at anode metals, which deliver electrons (the electricity) through the external circuit to the cathode metal, where reduction occurs.

Photographs (photographic print paper and conventional films) depend on photosensitization of AgCl, AgBr, AgI, followed by reduction of Ag+ to Ag metal by developer. In the case of color, reduction of the silver leads to expression of yellow, cyan, and magenta dyes in layers.