Useful Loners

Despite their unreactivity, noble gases are extraordinarily useful. Argon fills incandescent bulbs because it will not react with hot tungsten filaments, and provides an inert welding atmosphere.

Helium has the lowest boiling point of any element at -269°C, making it essential for cooling MRI machines and superconducting magnets. Xenon is used in high-performance headlights and ion propulsion engines for spacecraft.