1		2
				3
			4
	5														6
7														8
9											10		11
12					13
							14
			15	16			17			18
										19

Across 1. This gas is lighter but more flammable than helium 4. The noble gases are found in this group in the periodic table 7. This household item may contain argon 8. atomic number of neon 10. Element named after the greek word for 'sun' 12. Radon is hazardous because it is __________ 14. If something does not not easily combine with other elements, it is u________ 15. Between krypton and radon 19. Argon is used in welding to stop hot metal reacting with this gas

Down 2. some noble gases are obtained by fractional ____________ of air 3. The Noble gases used to be called this 5. Helium and neon are less dense than this 6. noble gas with atomic number 2 9. Gas named after greek word for 'hidden' 11. Helium can be used as a L_______ gas 13. Third most abundant gas in air 16. Argon lasers are used by these surgeons 17. Gas used in advertising signs 18. Do the Noble gases get more or less dense going down the group?