reactivity series metals alloys rusting electrolyisis Flashcards
reactivity series
K
Na
Li
Ca
Mg
Al
C
Zn
Fe
H
Cu
Ag
Au
react with water
K Na Li Ca
metal + water > metal hydroxide + hydrogen
potassium + water
> potassium hydroxide + hydrogen
- effervescence
- moves on surface of water
- melts into ball
- lilac flame
sodium + water
> sodium hydroxide + hydrogen
- effervescence
- moves on surface of water
- melts into ball
lithium + water
> lithium hydroxide + hydrogen
- effervescence
- moves on surface of water
calcium + water
> calcium hydroxide + hydrogen
- effervescence
- forms white precipitate
react with acids
Mg Zn Fe
metal + acid > salt + hydrogen
magnesium + hydrochloric acid
> magnesium chloride + hydrogen
- effervescence
- moves on surface
- disappears
zinc + hydrochloric acid
> zinc chloride + hydrogen
- effervescence
iron + hydrochloric acid
> iron chloride + hydrogen
- effervescence
copper + hydrochloric acid
no reaction
don’t react with acids or water
Cu Ag Au
(use displacement reactions to order them)
displacement reaction
use to see which metal is more reactive
- in terms of O2
oxidation - gain O2
reduction - loss O2
- in terms of e-
oxidation - loss e-
reduction - gain e-
magnesium + copper oxide
Mg + CuO
(displacement example - from metal oxide)
> magnesium oxide + copper
MgO + Cu
- bright white light
- exothermic
Cu displaced by Mg
Mg > oxidised (gain O2)
CuO > reduced (lost O2)
Mg is more reactive than Cu
magnesium + copper sulphate
Mg + CuSO4
(displacement example - from aq solution)
magnesium sulphate + copper
MgSO4 + Cu
- solution becomes paler
- pink brown solid disappears
Cu is displaced by Mg
Mg > oxidised (lost e-)
Cu2+ > reduced (gain e-)
Mg is more reactive than Cu
extracting metals
with carbon
electrolysis
metal ore
rocks that contain enough metal in a compound to be economical to extract
(metals can be extracted from their ore)
extracting with carbon
- used for metals less reactive than carbon
- heat with C/ CO - displaces metal from ore
eg 2CuO + C > CO2 +2Cu
C - oxidised - reducing agent
CuO - reduced
extracting by electrolysis
- used for metals more reactive than carbon
- expensive so carbon is preferable if it can be used
- uses lots of electricity
pure metals - bonding/properties
- metallic bonding - EA between cations and sea of delocalised electrons
- conducts elec- delocalised electrons free to move throughout structure
- malleable - layers of ions can slide over each other
alloy
mixture of metals with another metal or carbon - harder than pure metal
why is allot harder than pure metal?
- consists of diff. sized atoms
- layers distorted
- layers can no longer slide over each ither