Absorbs • Advantage • Allowing • Characteristics • Chemical • Combination • Combustion • Component • Consists • Construction • Contact • Control • Cooking • Devices • Efficiency • Energy • Engines • Excess • Expensive • Fuel • Greater • Higher • Hydrogen • Ignited • Inorganic • Levels • Liquid • Long • Lubrication • Metal • Motors • Need • Oxidizer • Oxygen • Plasm • Plastic • Provide • Purpose • Relatively • Rockets • Shuttle • Simple • Spacecraft • State • Supplies • Support • Type • Types • Which • Wood