SC11 & SC12 & SC13

Created by

Jenna

Cards (30)

what is the reactivity series?
the reactivity series is a list of metals arranged in order of their reactivity, with the most reactive metal at the top and the least reactive metal at the bottom
what is a displacement reaction?
a chemical reaction where one element is replaced by another element in a compound
what are spectator ions? 
ions that have been left out as they do not change
what is a redox reaction?
a reaction in which one substance is oxidised and another is reduced
what is extraction? 
the process of obtaining a metal from these compounds
what is an ore?
a rock that contains enough of a compound to extract a metal for profit
how are metal higher than carbon on the reactivity series extracted?
electrolysis
what elements are extracted by heating their ore with carbon?
zinc
iron
copper
what is bioleaching? 
uses bacteria grown on a low grade ore. the bacteria produce a solution containing metal ions called a leachate. the metal is extracted using displacement
what is phytoextraction? 
involves growing plants that absorb the metal compounds. the plant is then burnt to form ash which the metal is extracted from
what are some disadvantages of bioleaching?
toxic substances and sulfuric acid are produced which can damage the environment
very slow
what are some disadvantages of phytoextraction?
more expensive than mining
growing plants is dependent on weather
very slow
what are advantages of bioleaching?
no harmful gases are produced
causes less damage than mining
conserves supplies of higher grade ores
doesn't require high temperatures
what are advantages of phytoextraction?
no harmful gases produced
causes less damage to the landscapes
conserves supplies of higher grade ores
can extract metals from contaminated soils
when does corrosion happen?
when a metal reacts with oxygen, making the metal weaker over time. the metal gains oxygen so is oxidised
what is a tarnish?
some quite reactive metals don't corrode as they form a protective oxide layer which prevents further reaction
what are the main advantages of recycling?
natural reserves of metal ores last longer
less need to mine ores, less landscape damage
less pollution
less energy used to recycle than extracting
less waste metal ends up in landfill sites
why is a life cycle assessment carried out?
to assess environmental impacts of manufacturing a product
what are reversible reactions?
when reactants can react to form products and the products can react to form reactants
what is dynamic equilibrium?
when the forward and backward reactions are still occurring but the percentages of the reactants and products are no longer changing
what system does dynamic equilibrium occur in?
a closed system
what are properties of transition metals?
malleable
ductile
good conductors of electricity
shiny when polished
what do catalysts do?
increase the rate of a reaction without being changed chemically or in mass at the end of the reaction. transition metals show catalytic activity
what is sacrificial protection?
sacrificial protection is a corrosion prevention method where a sacrificial metal is used to protect a more valuable metal from corrosion
what is electroplating? 
coating the surface of one metal with a thin layer of another metal. it can also be used to improve a metal objects ability to resist corrosion
what do you need to electroplate a metal object?
an anode
an electolyte
a cathode
what is galvanising?  
iron and steel objects can be protected from rusting by coating them with zinc
what is an alloy?
a mixture of a metal element with one or more other elements, usually metals
what are alloy steels?
they are made by deliberately adding other elements to iron
why do stainless steels resist rusting?
they contain chromium which reacts with oxygen in the air and forms a layer of chromium oxide to stop air and water reaching the metal below