Carmirlyta Despeignes Chemistry
HELIUM In 1868, Pierre Janssen discovered Helium while he was observing a solar eclipse in India. Norman Lockyer discovered Helium the same way and it name the element after the Greek name for sun Helios. Norman Lockyer Pierre Janseen
HELIUM Atomic name Helium Atomic number 2 Atomic symbol He Atomic mass amu Helium has 2 protons, 2 electrons, and 2 neutrons. Helium is non-metal element.
ISOTOPES OF HELIUM Helium is represented in a gas form. Helium is in group 18. it is also found in period 1 and it is a noble gas because it has a stable shell: 2 electrons. Isotopes are two or more form of an element. Helium has seven isotopes, but two of them are stable: Helium-3: one neutron: % Helium-4: two neutrons: 99.99%the most used
WHAT HELIUM IS USED FOR Helium is used: to fill balloons As an artificial air for divers to fill blimps as a protective gas in growing silicon and some other elements. for pressuring liquid fuel rockets as a cooling medium for nuclear reactors as a gas for wind tunnels
IONIZATION ENERGY OF HELIUM Helium’s electron configuration is 2 or 1s2. Ionization energy is the energy that is required to remove a mole of electrons from an element. The ionization energy of Helium is cm -1
ATOMIC RADIUS/ ELECTRONEGETIVITY OF HELIUM The Atomic Radius of Helium is 31 PM. Electronegativity is the capacity of an atom to attract electrons in ionic bonds. The Electronegativity of Helium is 0.7
SOME OTHER FACTS ABOUT HELIUM Helium is the second lightest element. It is colorless, odorless, tasteless, and non-toxic. Helium cannot turn into a solid at a low temperature Helium has a weak capacity to bond with other elements.
LINKS helium/ K/Helium.html htm