unit 3A metals

• Why are metals good conductors?

  They have free to move delocolised electrons
• metals + oxygen → _____ _____

  Metal oxides
• metal + water

  metal hydroxide + hydrogen
• metal + dilute acid

  salt + hydrogen
• What is metallic bonding?

  The electrostatic force of attraction between positively charged ions and delocalised electrons
• what is an ore

  naturally occurring compound of a metal
• metals extracted from heating

  silver mercury and gold (unreactive,don't form compounds easily ) (metal oxide -> metal + oxygen)
• metals extracted with carbon

  zinc-> copper

  (moderate reactivity) (metal oxide -> metal + carbon dioxide )
• metals extracted from electolysis

  lithium-> alluminium

  (most reactive)( difficult to extract) (aluminium oxide-> aluminium + oxygen)
• what happens in electrolysis

  positive metal ions attracted to the negative electrode where they gain electrons. negative non metal ions are attaracted to the positive electrode where they loose electrons.
• electrochemical cells

  the metal with the higher force pushes its electrons on to the other metal
• electrochemical cells are made up of .... connected by

  two diffrent metals connected be an electrolyte (any soluble ionic compound )
• what is the purpose of the electrolyte

  complete circuit
• in electrolysis, electrons...

  flow through the wires from the metal higher in the electrochemical series, to the metal lower
• voltage investigation conclusion

  the further apart the two metals are on the electrochemical series, the higher the voltage produced
• Purpose of ion bridge

  to allow ions to move between 2 solutions
• why can cells contain a non metal

  as long as there is one reactive metal to give away the electrons, and another to accept them. you also need an ion bridge
• cells containing a non metal rules

  the metal which gives its away its electrons, has to be higher in the electrochemical series than the other substance so it can make an electric current.

  again the further apart the metal and other substance are, the higher the voltage.
• how are ionic bridges made

  from soaking a piece of filter paper in an ionic solution
• What is oxidation?


  loss of electrons (s)-> (aq) + e
• What is reduction?

  gain of electrons (aq) + e -> (s)
• What are redox reactions?

  REDuction and OXidation happen at the same time (REDOX)
• what metal will always be oxidised in an electrochemical cell

  the more reactive metal
• OILRIG

  oxidation is loss, reduction is gain
• in a redox equation, what must be the same

  number of electrons in equation
• less reactive metal is always

  reduced
• metal ions are always positively charged so therefore when it's changed from an ion to an atom


  involves the gain of electrons: reduction
• why does it become harder to remove metals from their ores as they go up in reactivity series

  the bonds in compound become more stronger and harder to break
• electrolysis


  to break up a compound using electrocity
• electrolysis set up

  dc power supply connected to carbon graphite electrodes submerged in ion compound
• Why is a D.C power supply used in electrolysis?

  so the products are identified and one product will end up at each electrode
• percentage composition

  1) work out formula

  2) work out gfm

  3) mass of element/ formula mass of COMPOUND X100
• electrochemical cell set up

  Voltmeter connected to two metal rods submerged in an ionic compound
• More complex cells

  Made by connecting two beakers containing two different metal

  solutions of their ions
• Complex cell set up

  Voltmeter connect to two metal rods each in their own beaker if there own ion solution with an ion bridge
• Writing redox

  equation

  1. Split both oxidation and reduction reaction into and make number of electrons in each the same

  2 break each reaction into products and reactants and combine both

  3 take away electrons
• Hydrochloride acid formula

  HCl
• Sulfuric Acid

  H2SO4
• Nitric Acid

  HNO3