THE NOBLE GASES

1. THE NOBLE GASES

2. Gp 0 H He He Li Be B C N O F Ne Ne Na Mg Al Si P S Cl Ar Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Xe Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Rn Fr Ra Ac Rf Db Sg Bh Hs Mt ? ? ? Group 0 the noble gases Coming after Group 7, you might expect these to be called Group 8 – and in some books they are. Group 0 is a better name though – because that’s what they do!

3. He Ne Ar Electron Structure and Reactivity 2 All the elements in this group have fully occupied outer shells. They are the least chemically reactive elements. The stable arrangement means that the noble gases do not form chemical bonds with each other or other elements. They are monatomic which means they exist as individual atoms. 2,8 2,8,8

4. Uses of Noble Gases You might think that a group of elements that have almost no reactions would have few uses. You would be wrong! They have many uses, mostly based upon their ability to prevent other (undesirable) reactions taking place.

5. Uses of Helium • Balloons (big and small). • Protective gas for growing silicon crystals in silicon chip manufacture. • Rare documents preservation (i.e. US Declaration of Independence). • Pressurizing agent for liquid fuel rockets (inert so won't react). • Coolant for the super-conductors used in body scanners.

6. Uses of Neon • Fluorescent lights and ‘neon’ signs. • TV tubes. • Neon lasers.

7. Uses of Argon • Used to fill light bulbs because the filament will not react with argon. • Used as an inert gas shield for arc welding and cutting especially metals easily damaged by oxygen such as aluminium & stainless steel. • Argon is involved in dating the ages of rocks by potassium-argon dating.

8. He Ar Ne Match the gas with the use

9. Patterns: Density! • There can be few chemical patterns for a group as unreactive as this. • There are still trends in physical properties

10. There are also trends in boiling point. • Can you predict the B.Pts of Kr Xe and Rn?

11. Which is NOTa true statement about the noble gases? • They contain shells that are full or empty • They are monatomic gases • They are un-reactive. • They are lighter than air

12. Which gas is used in normal light bulbs? • Helium • Neon • Argon • Krypton

13. Which gas is used in airships? • Helium • Neon • Argon • Krypton

14. Which gas is used in red fluorescent lights? • Helium • Neon • Argon • Krypton

15. Which gas is used to provide a shield of inert gas during arc welding of metals like aluminium? • Helium • Neon • Argon • Krypton