What is the chemical equation for chemosynthesis?

Chemosynthesis is a process by which certain organisms, typically bacteria, convert carbon dioxide and other inorganic compounds into organic matter using chemical energy sourced from the oxidation of substances like hydrogen sulfide or methane rather than sunlight, as is the case in photosynthesis.

The correct equation includes the reactants hydrogen sulfide (H2S), carbon dioxide (CO2), oxygen (O2), and water (H2O) and produces organic compounds (represented here as CH2O, which can signify simple sugars) along with sulfuric acid (H2SO4) as a byproduct. This reflects the biological processes that occur in environments such as hydrothermal vents, where organisms rely on chemical energy derived from the oxidation of hydrogen sulfide.

In contrast, the other options describe processes that do not represent chemosynthesis. The first option depicts photosynthesis, where light energy is used to convert carbon dioxide and water into glucose and oxygen. The third choice represents a non-standard reaction that does not adequately describe energy capture through chemosynthesis. The fourth choice describes the combustion of hydrogen, which is unrelated to the processes involved in chemosynthesis.