Extracting metals Flashcards
what is oxidation and reduction
the addition of oxygen and reduction is loss of oxygen
what does combustion reactions involve
oxidation and they’re always exothermic
what dos it mean if metal is below hydrogen in reactivity series
then it cannot react with hydrogen
what do metals at the top of reactivity series mean
easily oxidised so corrode easily
why are metals at the top of series most reactive
because the easily lose electrons to form cations
how can you identify the position of metal on reactivity series
react it with water or acid
how do metal reacting with acid tell you abt their reactivity
place different metals in acid
the more reactive, the quicker the reaction with acid
the more reactive metals fizz vigorously and less reactive bubble a bit
hydrogen is identified by burning splint , louder the squeaky pop more hydrogen made hence more reactive
the speed of the bubbles of hydrogen given off show the reactivity of metals
how do metals reacting with water show its reactivity
very reactive metals will react vigorously and less reactive will be slower
What is oxidation and reduction in terms of electrons
oxidation is loss of electrons reduction is gain of electrons
what is a displacement reaction
when a more reactive element displaces a less reactive element
which element is oxidised and reduced
the more reactive element is oxidised and less reactive element is reduced
how can you find reactivity of metals using displacement reactions
place metals to metal salt solutions and record the order of reactivity
what is a metal ore
a rock that contains enough metal to make it economically valuable
where are metal ores found
in the Earths crust then extracted from ores and unreactive metals are found in the crust as uncombined elements easily mined out
how can a metal be extracted using carbon
using reduction, when ore is reduced the oxygen is removed from it
what is the reactivity series
potassium sodium calcium magnesium aluminium carbon zinc iron copper silver gold
what elements can be extracted using electrolysis
what elements can be extracted by reduction using carbon
what are found as pure elements
metals higher than carbon as it is too reactive which is expensive
metals below carbon using carbon and a blast furnace which is cheaper
gold and silver
What is bleaching
the use of bacteria to separate metals from ores , energy is taken from bonds between atoms in ores causing the metals to separate and leachate being produced with contains metal ions which can be extracted by electrolysis or displacement reactions
what is phytomining
plants absorb metals through their roots
plants are grown in areas with metal compounds
As the plants grow the metals are taken up through the plants and become concentrated in the leaves
These parts of the plant are harvested, dried and burned
The resulting ash contains metal compounds from which the useful metals can be extracted by displacement reactions or electrolysis
why is bioleaching and phyto mining beneficial
because it doesnt damage the enviroment by producing pollutants unlike traditional methods
how does recycling conserve energy
extracting metals produces lots of energy which come from burning fossil fuels so recycling metals means less energy is needed to extract and refine metals from scratch
how does recycling conserve resources
fossil fuels are running out so it is important to conserve them as they contribute to acid rain and climate change
also finite
how does recycling protect the environment
- It is much more energy efficient to recycle metals than it is to extract them less energy
- Recycling decreases the amount of waste produced, hence saving space at landfill sites and energy in transport and reduces pollution in landfills
- mines damage the environment and destroy habitats
how is recycling economically beneficial
- Recycling is fast becoming a major industry and provides employment which feeds back into the economy
- saves money as its expensive to buy and extract metals
what should you keep in mind in a life cycle assessment
choice of material
manufacture
usage
disposal
what is choice of material
is the material finite
is it fossil fuel - produce lots of energy and generate pollution
does it destroy habitats like deforestation
what is choice of material
is the material finite
is it fossil fuel - produce lots of energy and generate pollution
does it destroy habitats like deforestation
what is manufacture
products use a lot of energy which cause pollution
Using up land for factories
The use of fossil fuelled machines for production and transport
does it need water - shouldn’t be polluted back into Environment
what is product use
how does it damage environment
does it give off toxic fumes
greenhouse gases or
what is disposal
disposal at landfill sites cause pollution and pollute rivers and land
could cause air pollution
