Helium Uses
Helium Uses - Related Videos
03:48
Behavior of Gas Molecules: Molecular Diffusion, Mean Free Path, and Effusion
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2020
Although gaseous molecules travel at tremendous speeds (hundreds of meters per second), they collide with other gaseous molecules and travel in many different directions before reaching the desired target. At room temperature, a gaseous molecule will experience billions of collisions per second. The mean free path is the average distance a molecule travels between collisions. The mean free path increases with decreasing pressure; in general, the mean free path for a gaseous molecule will be...
02:13
Nuclear Binding Energy
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2020
The difference between the calculated and experimentally measured masses is known as the mass defect of the atom. In the case of helium-4, the mass defect indicates a “loss” in mass of 4.0331 amu – 4.0026 amu = 0.0305 amu. The loss in mass accompanying the formation of an atom from protons, neutrons, and electrons is due to the conversion of that mass into energy that is evolved as the atom forms. The nuclear binding energy is the energy produced when the atoms’ nucleons are bound together;...
02:45
Nuclear Fusion
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2020
The process of converting very light nuclei into heavier nuclei is also accompanied by the conversion of mass into large amounts of energy, a process called fusion. The principal source of energy in the sun is a net fusion reaction in which four hydrogen nuclei fuse and ultimately produce one helium nucleus and two positrons. A helium nucleus has a mass that is 0.7% less than that of four hydrogen nuclei; this lost mass is converted into energy during the fusion. This reaction produces about...
03:07
Kinetic Molecular Theory: Molecular Velocities, Temperature, and Kinetic Energy
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2020
The kinetic molecular theory qualitatively explains the behaviors described by the various gas laws. The postulates of this theory may be applied in a more quantitative fashion to derive these individual laws. Collectively, the molecules in a sample of gas have average kinetic energy and average speed; but individually, they move at different speeds. Molecules frequently undergo elastic collisions in which the momentum is conserved. Since the colliding molecules are deflected off at different...
12:27
Assembly, Tuning and Use of an Apertureless Near Field Infrared Microscope for Protein Imaging
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Cited by 3 •
2009
The assembly of a nearfield infrared microscope for imaging protein aggregates is described.
FAQs
A filled electron shell leaves helium chemically inert, so it does not readily participate in reactions with materials around it. This behavior allows helium to provide a controlled atmosphere when reactive substances must be handled without oxidation or contamination. In chemistry and industrial processes, its value comes from maintaining environmental control while minimizing unwanted chemical interactions.
Helium’s exceptionally low density enables balloons and airships to obtain lift while avoiding the chemical reactivity associated with other gases. Its inert character is especially important in these applications because the gas can support buoyancy without readily reacting with surrounding materials. The combination of low density and low reactivity explains helium’s continuing engineering relevance in lighter-than-air systems.
Helium’s very low boiling point allows it to function as a cryogenic coolant, meaning a substance used to achieve extremely low temperatures. This property is important for cooling superconducting magnets, including those used in magnetic resonance imaging. The cooling role connects helium’s physical behavior directly to advanced medical equipment and research systems requiring controlled low-temperature operation.
Helium can assist leak detection because its small atoms are able to penetrate tiny leaks that may be difficult to identify by other means. A system can therefore be examined for helium passage through extremely small openings, making the gas useful for checking containment and integrity. This application relies on helium’s physical size rather than its chemical reactivity.
During arc welding, helium can provide a chemically inert surrounding atmosphere that limits unwanted interactions with the materials being joined. This shielding function helps reduce oxidation and contamination during the process. The same principle extends to laboratory and industrial handling of reactive materials, where maintaining an inert environment helps protect substances and preserve controlled processing conditions.
Helium serves as one of the gases used in gas chromatography, a technique applied in chemical analysis. Its usefulness in this setting is consistent with its chemical inertness, which supports controlled handling of substances during laboratory work. More broadly, helium provides an atmosphere that helps prevent oxidation and contamination when researchers need chemically controlled conditions.