4.1 Obtaining and using metals Flashcards
What will the most reactive metals react with?
Cold water
Fairly reactive metals react with what?
Acids
What do almost all metals react with?
Oxygen
How can you see if one metal is more reactive than another?
Using displacement reactions
In a displacement reaction what do the more reactive metals form?
Cation
Why do more reactive metals form cations?
.They displace the less reactive metal, losing electrons and therefore have been oxidised
What do less reactive metals form?
Anion
Why do less reactive metals form an anion?
.They are displaced, gaining electrons and therefore being reduced
What are the first 4 elements in the reactivity series?
Potassium
Sodium
Calcium
Magnesium
What are the middle 4 elements in the reactivity series?
.Aluminium
.Carbon
.Zinc
.Iron
What are the last four elements in the reactivity series?
Hydrogen
Copper
Silver
Gold
What is the reactivity of a metal related to?
Its tendency to form positive ions
Where are most metals extracted from?
.From ores in the Earths crust
Where are unreactive metals from?
.Found in the Earth’s crust as uncombined elements
What is oxidation?
.The gain of oxygen
What is reduction?
The loss of oxygen
Are metals more or less reactive than carbon?
Less reactive
How can metals be extracted from their oxides?
Reduction with carbon
When can a metal be extracted by reduction with carbon?
If it is less reactive, so the carbon can displace it
What technique would you use to extract a metal if it is more reactive than carbon?
Electrolysis
Why is electrolysis expensive?
.Due to the large amounts of energy used to melt the compounds and to produce the electrical current
Name the two alternative biological methods of metal extraction
.Phytoextraction
.Bacterial extraction
Give the process of phytoextraction
.Some plants absorb metal compounds through their roots
.These are concentrated into their shoots and leaves
.These can be burned to produce an ash that contains the metal compounds
Give the process of bacterial extraction
.Some bacteria absorb metal compounds
.Produce solutions called leachates which contain them
.Scrap ron can be used to obtain the metal from the leachate
What is a metals relative resistance to oxidation the same as?
Its relative resistance to losing electrons/ forming positive metal ions
How is mining ores bad for the environment?
.Large quarries are created which produces noise pollution and dust
What does recycling allow for?
.Waste materials to be reused
Why are lifetime assessments of a product carried out?
To assess the environmental impacts of products in the stages of a product life