We use helium in balloons
Helium is a chemical element
with the symbol He and atomic number 2.Helium is a colorless, tasteless and
odorless gas. Helium is the second most common element in the Universe (after
hydrogen), making up around 24% of its mass. Helium is part of a group of
chemical elements called noble gases, the other five that occur naturally are
neon, argon, krypton, xenon and radon. Under normal conditions they share
similar properties, including being less likely to participate in chemical
reactions due to their outer shell of electrons being full. Helium is the
second least reactive element after neon. French and English astronomers Pierre
Janssen and Norman Lockyer are jointly credited with discovering helium after
spectral analysis of sunlight following a solar eclipse in 1868. The word
helium comes from the Greek word meaning sun (helios). It was named by Lockyer
and English chemist Edward Frankland. The USA is the world’s largest supplier
of helium, with many reserves found in large natural gas fields.
The rate at which helium is
currently being used by humans is much faster than the rate at which the
reserves are being replenished. New technologies for obtaining or recycling
helium are one way for gas companies to help slow this problem. Because helium
is lighter than air it is commonly used to fill airships, blimps and balloons. While
hydrogen is 7% more buoyant than helium it has a much higher fire risk. You
might notice the helium balloon you got from the amusement park slowly falling
to the ground after a few days, this happens as the helium gradually leaks from
the balloon.
Because helium is less dense
than normal air, when inhaled from a source such as a helium balloon it briefly
changes the sound of a person’s voice, making it much sound much higher.
However, breathing in too much helium can be very dangerous, potentially
choking people due to a lack of oxygen. Helium can be in a liquid and even
solid state but they can only occur at temperatures near absolute zero. Liquid
helium is used to cool metals for superconductivity use. The European Organization
for Nuclear Research’s (CERN) Large Hadron Collider uses liquid helium to
maintain an extremely low temperature. Helium is often used in space programs,
displacing fuel in storage tanks and having other rocket fuel applications.
other scientists have warned
that helium is becoming so scarce that research that makes use of its cooling
power may have to be limited or stopped. Although it is the second most
abundant element in the universe, helium cannot be manufactured, and once
released into the atmosphere is lost for ever. Most of our supplies are
extracted from the earth's crust.
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