Editing High-test peroxide (section)

==Properties==
Hydrogen peroxide works best as a propellant in extremely high concentrations (roughly over 70%). Although any concentration of peroxide will generate some hot gas (oxygen plus some steam), at concentrations above approximately 67%, the heat of decomposing hydrogen peroxide becomes large enough to completely vaporize all the liquid at standard pressure. This represents a safety and utilization turning point, since decomposition of any concentration above this amount is capable of transforming the liquid entirely to heated gas (the higher the concentration, the hotter the resulting gas). This very hot steam/oxygen mixture can then be used to generate maximal thrust, power, or work, but it also makes explosive decomposition of the material far more hazardous.

Normal propellant-grade concentrations, therefore, vary from 70 to 98%, with common grades of 70, 85, 90, and 98%.<ref>{{cite web |url=https://www.hydrogen-peroxide.us/chemical-specifications/MIL-PRF-16005F_Rocket_Propellant_Hydrogen_Peroxide.pdf |title=MIL-PRF-16005F Performance Specification: Propellant, Hydrogen Peroxide |work=Department of Defense Index of Specifications and Standards |date=1 August 2003 |access-date=12 November 2016 |via=Whiskey Yankee LLC}}</ref>

The volume change of peroxide due to freezing varies with percentage. Lower concentrations of peroxide (45% or less) will expand when frozen, while higher concentrations (65% or greater) will contract.<ref>{{cite web|url=https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20100040598.pdf|title=Fire, Explosion, Compatibility and Safety Hazards of Hydrogen Peroxide|publisher=NASA}}</ref>{{rp|4–39}}

Hydrogen peroxide becomes more stable with higher peroxide content. For example, 98% hydrogen peroxide is more stable than 70% hydrogen peroxide. Water acts as a contaminant, and the higher the water concentration the less stable the peroxide is. The storability of peroxide is dependent on the surface-to-volume ratio of the materials the fluid is in contact with. To increase storability, the ratio should be minimized.<ref>{{cite conference|title=Long Term Storability of Hydrogen Peroxide|last1=Ventura|first1=Mark|conference=41st AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit|journal=AIAA|publisher=General Kinetics Inc|id=AIAA-2005-4551}}</ref>