(1)(a) Fewer than one quarter of the elements are
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive .
(b) Non-metal elements are found in the groups at the
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive hand side of the periodic table.
(c) The elements in Group 7 the
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive , and Group 0 the noble
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive , have the typical properties of
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive - they have
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive melting points and boiling points.
(d) As you go up the group the density, and melting and boiling points get
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive .
(2)(a) The noble gases are all
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive gases at room temperature and pressure.
(b) They are chemically very
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive gases and exist as
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive atoms rather than as
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive gases like other gaseous
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive such as oxygen O
2 , or hydrogen H
2 .
(c) They are used in electrical discharge tubes eg '
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive ' lights and as
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive gases in filament lamps because they are so unreactive and will not
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive the filament.
(3)(a) The first element in the Group,
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive , has a density much
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive than air and is used in balloons.
(b) Unreactive helium is safer to use in balloons than
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive which is
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive in air.
(c) They are very
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive because the outer
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive of electrons is
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive .
(d) This means the atom does not wish to gain, share of donate electrons to form a chemical
bond burn colourless diatomic elements flammable full gases halogens helium higher hydrogen inert low lower neon non-metals right shell single unreactive .