Anaerobic decomposition or anaerobic digestion.
Anaerobic digestion
Oxygen is not use.Oxygen is produced in photosynthesis when breaking of water molecules to obtain electrons.
Water molecules separating means they are spreading, or in other words, the water is evaporating. When they are breaking apart, the hydrogen and oxygen are separating.
fermentation
Respiration
cellular respiration
The release of energy from food molecules in the absence of oxygen is called anaerobic respiration. When there is oxygen present it is called aerobic respiration.
Oxygen is not flammable; but because oxygen is an oxidizing agent burning is not possible without oxygen.
This cannot be answered without knowing how much oxygen there is. ===== Each molecule of oxygen consists of two atoms of oxygen.
Carbohydrates molecules are made of carbon, hydrogen, and oxygen. If it had only carbon and hydrogen (and no oxygen) it would be called a hydrocarbon.
Glycolysis does not depend on oxygen. It is the anaerobic part of cellular respiration and can produce 2 molecules of ATP without oxygen.
fermentation