metals and plastics Flashcards
metal properties
shiny, grey (usually) malleable (can be worked into shapes) strong conduct electricity and heat wide range of melting and boiling points
metallic bonding definition
the electrostatic force of attraction between positively charged ions and delocalised electrons
oxygen reaction with metals
metal + oxygen = metal oxide
metal and water reaction
metal + water = metal hydroxide + hydrogen
metal and acid reaction
metal + acid = salt + hydrogen
metals naturally react with oxygen/water/acid forming…
metal ores
metals are extracted from ores by:
heat alone
heat with carbon
electrolysis
electrochemical series:
heat alone
silver to gold
electrochemical series:
heat with carbon
zinc to copper
electrochemical series:
electrolysis
lithium to aluminium
describe electrolysis
during electrolysis, positive metal ions are attracted to the negative electrode and negative non-metal ions are attracted to the positive electrode
reduction of lithium
Li+ + e- ~ Li
oxidation of lithium
Li ~ Li+ + e-
explain a simple cell
a simple cell can be made by placing two metals in an electrolyte
electricity conducting solutions containing ions are known as…
electrolytes
describe the voltage in electrochemical cells
the further apart elements are in the electrochemical series, the greater the voltage produced when they are used to make an electrochemical cell
OIL RIG
oxidation is loss (of electrons)
reduction is gain (of electrons)
half cells contain metals in solutions…
of their own ions
what is an ion bridge
soaking electrolyte, links the 2 half cells together, ions can move across the bridge to complete the electrical circuit
electrons flow from the species higher in the ECs…
to the species lower
electricity can be produced in…
where at least one of the half cells does not involve metal atoms/ions
what can be used as the electrode in such half cells
a graphite rod
what are polymers
they are long chain molecules formed by joining together a large number of small molecules called
addition polymerisation
small unsaturated monomer (e.g. alkenes) join to make one large polymer
