Page 41 - Curriculum Visions Dynamic Book

Collecting helium
We cannot make helium by any chemical means because it is
not locked in any compounds, so all the helium we use has to be collected, along with natural gas, from gas fields. The majority of the world’s helium comes from Texas, Utah, Oklahoma and Kansas.
inert: nonreactive. There are few substances that hardly react. They include all the rare gases (helium, neon, argon, krypton, xenon and radon).
 The extremely low boiling point of helium makes it useful for studying matter at very low temperatures, a type of research known as cryogenics (from the Greek word for “frost”).
Airship
An airship is a type of lighter-than-air craft using a balloon for buoyancy and an engine to propel it. It carries a small passenger compartment – known as a gondola – below the balloon. Airships used to be filled with hydrogen because of the excellent lift this provided, but the fire hazards with hydrogen mean that all modern balloons are filled with helium.
Airships have to float at a desired height. Old airships used ballast that could be thrown overboard to allow the airship to rise. To make it sink, hydrogen gas was released from the balloon.
Helium is too precious to be released in this way, and throwing
out ballast is hazardous for those below. Extra ballast is now provided by causing water vapour in the air to condense, adding weight by increasing the amount of water condensed.
Also...
A mixture of 80% helium and 20% oxygen is used as an artificial atmosphere for deep sea diving. Helium is used instead of nitrogen because it does not cause the “bends”. Its use has
a remarkable effect on
the vocal chords, making people who breathe the gas sound like Mickey Mouse!
Cold helium
Helium boils below any other element. It can only be liquified at -269°C, just four degrees above absolute zero, the coldest it is possible to get. Helium is also the one element that cannot be made to go into a solid at normal pressures. It remains liquid even close to absolute zero.
At these low temperatures helium behaves very strangely, having an ability to conduct heat 600 times as well as copper, flowing uphill, climbing up and over the walls of the flask containing it, moving almost without friction and going through the tiniest of holes. For these reasons, some scientists think that cold helium may be a fourth state of matter.
Helium is the best refrigerant in the Universe. It is used on space shuttles to cool the hydrogen and oxygen fuels, both of which have to be kept in liquid form during the journey. So helium, the gas of space, has a vital role to play in affecting our first steps into space.
The main use of helium on Earth is for cooling down scientific equipment for special purposes. Body scanners, for example, rely on helium.
41