Register for free to see more content


A propellant is a chemical material that can be burned to create pressurised gases. The energy from these gases is used to propel a rocket against the gravitational force of attraction. A propellant is a mixture that contains a burning fuel and an oxidizer.
An oxidizer is a chemical needed for the fuel to burn or combust. It provides the oxygen needed for the fuel to burn or combust.
1. Oxygen
2. Ozone
Types of propellants:
The propellants may be liquid or solid in nature. There are three types of propellants.
1. Liquid propellants:
Fuel and oxidizers are mixed in a combustion chamber in liquid propellants. In the chamber, they burn and eject with great force from the rocket's base. Liquid fuels include liquid hydrogen, hydrazine, and ethyl alcohol. Oxygen, ozone, hydrogen peroxide, and fuming nitric acid are some of the oxidizers.
Fuel: Liquid hydrogen
Oxidizer: Fuming nitric acid
2. Solid propellants:
Fuel and oxidizer compounds are already mixed together in solid rocket propellants. They burn and emit heat energy when they are ignited. Once a solid propellant is ignited, it cannot be prevented from combustion. Polyurethanes and polybutadienes are solid fuels used in rockets. Oxidizers include nitrate and chlorate salts.
Fuel: Polyurethane and polybutadiene
Oxidizer: Nitrate salts
3. Cryogenic propellants:
The fuel or oxidizer, or both, are liquefied gases contained at a very low temperature in these cryogenic propellants. There is no necessity for an ignition system as they react to the mixing and light their own flame.
Cryogenic propellant