4key differences between mendelelv’s table and the modern periodic table
how did mendeleev arrange the elements in his periodic table?
how did the discovery of gallium prove mendeleev’s table was correct?
how is the modern periodic table arranged?
what separates metals and non-metals on the periodic table?
‘stairway to boron’
(B, Si, As, Te, At)
general properties of metals
general properties of non-metals
which group has the most reactive metals and why?
group 1 - alkali metals
only need to lose 1 electron to get a full outer shell
which group has the most reactive non-metals and why?
group 7 - halogens
just need to gain 1 electron to get full outer shell
which group is unreactive and why?
group 8/0 - noble gases
already have full outer shells
what are properties of alkali metals?
how does the melting point of alkali metals change a you go down the group and why?
how does lithium react with water?
2Li(s) + 2H20 (g) -> 2LiOH (aq) + H2(g)
- move around the surface of water
- lots of fizzing (hydrogen gas)
- solution becomes alkaline due to lithium hydroxide produced
how does sodium react with water?
2Na(s) + 2H20(g) ->2NaOH(aq) +H2(g)
- move around the surface of water
- more fizzing than lithium (hydrogen gas)
- melts due to heat of reaction
- solution becomes alkaline due to sodium hydroxide produced
how does potassium react with water?
2K(s) + 2H20(g) ->2KOH(aq) +H2(g)
- move around the surface of water
- more fizzing than potassium ad lithium (hydrogen gas)
- sets on fire (lilac flame)
- melts due to heat of reaction
- solution becomes alkaline due to sodium hydroxide produced
how do rubidum and caesium react with water?
explode on contact with water
(react very vigourosly)
as you move down group 1, … (3)
why does reactivity increase as you go down group 1?
what common properties do all group 1 compounds have?
what are 4 common properties of halogens (group 7) ?
what colour and state is flourine at room temp?
yellow gas
what colour and state is chlorine at room temp?
green gas
what colour and state is bromine at room temp?
red/brown liquid
what colour and state iodine at room temp?
dark grey solid