Final answer:
Helium is the inert gas typically used in leak detection. It is chemically non-reactive and can be easily detected even at low levels. Helium is also used in various applications such as balloons, lasers, and cooling superconducting magnets.
Step-by-step explanation:
The inert gas typically used in leak detection is helium. Helium is chemically non-reactive and can be easily detected even at low levels. It is often used to detect leaks in vessels and high-vacuum apparatus. Helium is also commonly used in balloons, lasers, and cooling superconducting magnets for imaging studies.