Write two main characteristics of Rocket fuel.

Hint
Rocket fuel is a chemical substance that is used as a propellant to induce thrust or propulsion of a rocket to launch the rocket into space above the atmosphere of the earth.

Complete step by step answer
There are two types of fuel that are used in the rocket namely, solid fuel and liquid fuel. The components of liquid fuel are liquid hydrogen and liquid oxygen and the components of solid fuel are aluminum and ammonium perchlorate. However, both liquid and solid fuel are required to launch a rocket into space. Engines and boosters in a rocket consist of both solid fuel and oxidizer such that oxidizers work towards burning the fuel. The main characteristics of rocket fuel are as follows:
The very first types of liquid fuels used in a nearly successful rocket were gasoline and liquid oxygen, that are used and readily available in current times as well.
Some rocket propellants or fuels are highly inflammable, corrosive, and toxic in nature. An example of a highly inflammable liquid rocket propellant that must be handled with care is gasoline.

Additional information
Some other characteristics of rocket fuels are:
(i) Rockets are launched from the ground using solid fuels and the liquid fuel is burned and used to keep the upward propulsion of the rocket into space.
(ii) Solid fuels require less maintenance but provide a low value of specific impulses.

Note
Some types of propellants used in rockets are used in huge quantities. Solid fuels and liquid fuels may have advantages or disadvantages over one another but both are used in rockets for adequate launch.