Because of free electron pairs on both oxygen atoms, the H₂O₂-molecule tends to form donor-acceptor compounds. Pure hydrogen peroxide is primarily of scientific interest only. However, its aqueous solutions are widely used in cleaning and sanitization, electronics, mining, chemical synthesis, the bleaching of textiles, laundry and hair, in the pulp and paper industry, as a rocket fuel, antiseptic, antichlor, seed disinfectant, as a bleach and oxidizing agent in food and fish farming or as a substitute for chlorine in water and water and wastewater treatment. Important physical properties of hydrogen peroxide and its aqueous solutions as summarized in the table below. 

The molecular structure as well as oxygen's oxidation state define the chemical properties of hydrogen peroxide. The oxygen atom, being in the oxidation state I, allows hydrogen peroxide to participate in both oxidation as well as reduction reactions.

Although hydrogen peroxide is well known as a peroxide and powerful oxidizing agent with disinfectant, antiviral and antibacterial activities; its reduction properties play an important role in some applications. Typical chemical reactions, in which hydrogen peroxide is involved, are oxidation and reduction reactions, formations of other peroxygen or adduct compounds. In contrast to many other redox agents, hydrogen peroxide introduces no additional substances other than water into the reaction system and an excess can be easily decomposed into water and oxygen, not interfering thereby with subsequent reaction steps. Hydrogen peroxide solutions are often considered true "green chemistry."

Despite its high reactivity, pure hydrogen peroxide is a stable substance and, if kept under optimal conditions, can be stored for years. The most important factors increasing the rate of decomposition are high pH value, high temperatures, UV irradiation, presence of transition metal salts and all kinds of impurities. 

The decomposition of peroxide hydrogen into oxygen and water is a quite complex process, which involves formation of various free radicals that destroy pathogens and prevent spreading of infection. In some applications such as soil remediation the induced instability is intentionally caused and used.