Chemical rockets
are the most common type of high power rocket, typically creating a high speed exhaust by the
combustion
of
fuel
with an
oxidizer
. The stored propellant can be a simple pressurized gas or a single
liquid fuel
that disassociates in the presence of a catalyst (
monopropellant
), two liquids that spontaneously react on contact (
hypergolic propellants
), two liquids that must be ignited to react (like kerosene (RP1) and liquid oxygen, used in most
liquid-propellant rockets
), a solid combination of fuel with oxidizer (
solid fuel
), or solid fuel with liquid or gaseous oxidizer (
hybrid propellant system
). Chemical rockets store a large amount of energy in an easily released form, and can be very dangerous. However, careful design, testing, construction and use minimizes risks.
