topic 5 Flashcards
(19 cards)
transition metals properties
hard,strong,shiny,malleable
conduct heat+electricity
high melting points
high densities
useful
do transition metals compounds back good catalysts
yes
iton is catalyst for harber process
are transition metals colourful
yes
what happens when metals arnt strong enough for certain uses
alloys are used
how are the alloys for netal made
adding snother element to the netal
what happens when carbon is added to iron
carbon atoms will upset the layers of pure uron atoms
making it more difficuly for them to slide over rachother
so less malluble
stronger
bronze
copper and tin
hard
medals,decor,statues
brass
copper and zinc
malleable
water taps,door fittings
gold alloys
zinc,copper n silver strengthn gold
jewellery
aluminium alloys
other metals to increase strength
aircraft manufacture bc low density
what reaction is rusting of iron
redox
what is corrosion caused by
redox reactions
metal loses electrons so its oxidised
oxygen gains electrons when it reacts w metal
iron nail oractical
-nail in boiled water w no air and oil. boiling=no oxy, oil=stop air getting in
-nail in calcium chloride n air.cc=asorb water from air
-iron nail in water and air it will rust
how to prevent rusting
iron batrier
painting
oiling or greasing
sacrifical protection
galvanising
iron barrier
keeps out water oxygen or both
sacrifical protection
more reactice metal with the iron. water n oxygen react w this sacrificial metal instead od objevt ur protecting
electroplating
-coating surface of metal with another metal using electrolysis
-cathode=object ur gnna electroplate
-anode=bar of metal ur using for the olating
-electrolyte=solution w metal ions
percentage yield
actual yield/theoretical yield x100
atom economy
total mr of disired product/total mr of all products x100
