Question

Which of the following is not used as a propellant in rockets?

• A. Liquid hydrogen
• B. Poly butadienes
• C. Ethyl alcohol
• D. Coal

Answer 1

The correct option is D Coal

There are three types of propellants with each having corresponding oxidizers. Some common propellants are:

• Liquid propellants:
  • Fuels used- liquid hydrogen, ethyl alcohol, etc.
  • Oxidizers used- oxygen, ozone
• Solid propellants:
  • Fuels used- poly urethanes, poly butadienes, etc.
  • Oxidizers used- nitrate and chorate salts.
• Cryogenic propellants