When excited electrically, xenon (sometimes mixed with krypton) produces a brilliantwhite flash of light that makes it useful as the gas in strobe lights. The flash used in photog-raphy can repeatedly be used to provide a well-balanced light for illumination. The xenon inflash tubes is not consumed and can be flashed over and over again.
Xenon lamps are also used as an antiseptic to kill bacteria, to power lasers, and as tracers.Because of its high atomic mass, xenon ions are preferred as fuel for ion engines to powerspacecraft in deep space.
Xenon, another gas occurring in the air to theextent of 1 part in 11 million, is the heaviestof the rare gases. When atomic reactors are operated at high power, xenon tends to buildup as a reaction product, poisoning the fuel andreducing the reactivity. Xenon lamps for militaryuse give a clear white light known as sunlightplus north-sky light. This color does notchange with the voltage, and thus the lampsrequire no voltage regulators. Xenon is a mildanesthetic; the accumulation from air helps toinduce natural sleep, but it cannot be used insurgery since the quantity needed producesasphyxiation.
