Rocket propellant is a mixture of combustible substances that is burned inside the combustion chamber of a rocket engine. Burning is the chemical process of decomposition and oxidation of the propellant. The resulting highly heated and compressed gas (propulsive mass) is ejected from a combustion chamber and facilitates propulsion—movement of the aggregate attached to the rocket engine. In physical terms, combustion converts chemical energy into kinetic energy.

Rocket propellants possess unique properties, such as a capability to self-sustain the burning process, generate thermal energy, and simultaneously produce propulsive mass. Some types of propellants are even able to self-ignite (initiate burning without outside power input). Unlike most other combustible chemicals, rocket propellants can burn in vacuum. This is because a propellant consists of two integral components: a fuel that burns and produces propulsive mass and an oxidizer that facilitates and sustains oxidation. In this respect...