CHEM paper 3 Flashcards
What is electrolysis?
When electricity breaks down acidified water into hydrogen and oxygen
Whats an electrolyte?
An ionic substance with freely moving ions
Why can electric solids not be electrolysed
As the ionic bonds haven’t broken due to its solid state so no ions can freely move
Are cations positive or negative? What are they attracted to?
POSITIVE IONS and are attracted to the NEGATIVE cathode
Are anions positive or negative? What are they attracted to?
NEGATIVE ions and are attracted to the POSITIVE anode
what does OILRIG stand for
Oxidisation Is the Loss of electrons
Reduction Is the Gain of electrons
What is a displacement reaction
Only work one way so a less reactive metal cannot displace a metal more reactive
What is extraction
Process of obtaining metal from a compound
What is an ore
A rock that contains enough of a compound to extract a metal for profit
What is oxidisation
The gain of oxygen by a substance
What is reduction
The loss of oxygen from a substance
How is iron obtained
By removing oxygen from iron oxide by heating with carbon. The iron oxide is reduced to iron and the carbon is oxidised to carbon dioxide
What is corrosion
Happens when a metal reacts with oxygen, making a metal weaker overtime.
What is rusting
When a metal reacts with oxygen and water
What are the four stages of a life cycle assessment
Obtaining and processing raw materials
manufacturing and packaging the product
using the product
disposal of product
What is meant by recycling metals
Melting metals down and making them into something new
Whats a reversible reaction
When products react to form rectants, both forward and backward reactions happen at one time
What is dynamic equilibrium
When the forward and backwards reactions are happening but the percentages of the reactants products are no longer changing
Where does dynamic equilibrium occur
Occurs in closed systems where there is no loss of reactants or products
Whats an open system
Where gasses can escape and so equilibrium would not be achieved
