Flashcards in C1 - Metals & Their Uses Deck (41)
What happens to the ore in order to extract the metal?
The ore is mined and usually needs to be concentrated before the metal is extracted and purified.
What is a metal ore?
A rock containing enough of the metal to make it economically viable to extract the metal.
Give two factors that affect whether a rock is a metal ore.
-How easy it is to extract the ore.
-How much metal the ore contains.
What type of metals can be found in their native state?
Unreactive metals such as gold and silver
How is it decided which method of extraction to use in particular metal?
Which metals are extracted using carbon?
Less reactive metals.
How is carbon used to extract metals from their ores?
The metal oxide is heated with carbon which removes the oxygen from the metal oxide to form carbon dioxide.
Give the word word equation between a low-reactivity metal oxide with carbon.
metal oxide + carbon --> metal + carbon dioxide
What is the removal of oxygen from a compound called?
How are metals more reactive than carbon extracted by their ores?
How is iron ore reduced?
Iron is extracted using carbon in a blast furnace.
Why isn't iron from a blast furnace useful?
Pure iron is too soft.
How is iron changed to be made useful?
Specific quantities of carbon and other elements are added to make alloys of steel with varying properties.
What are the main types of steel?
-Low carbon steels which are easily shaped.
-High carbon steels which are very hard.
-Stainless steels which are resistant to corrosion.
What other elements do stainless steels contain?
Chromium or nickel
Give one key advantage of chromium nickel steels over iron steels.
They do not rust
Give two advantages of aluminium and titanium
They are both corrosion resistant.
They are both strong and light.
Which method is used to extract aluminium from its ore?
Why are aluminium and titanium resistant to corrosion?
They both have an oxide layer on the outer surface.
Give one disadvantage of electrolysis
The process is very expensive because of the energy needed to melt the compound.
How is titanium extracted?
The original titanium oxide is converted to a chloride which is distilled to purify then the titanium is displaced by sodium or magnesium.
How is copper extracted from copper rich ore?
Through the process of smelting or using sulfuric acid.
How is copper extracted from low-grade ores?
Bioleaching using bacteria or plants through phytomining.
How is copper purified after extraction?
Give one disadvantage of heating copper sulphide in air.
It produces sulphur dioxide gas which causes acid rain.
Give the word equation for the decomposition of chalcocite.
copper sulfide + oxygen --> copper and sulfur dioxide
How is acid rain prevented in chimneys?
Through the use of scrubbers which neutralise acidic gas.
Give the word equation for the displacement of copper using iron.
iron + copper sulfate --> iron sulfate + copper
Describe the process by extracting copper using phytomining.
Plants can absorb copper irons from discarded waste, then the plants are burnt and the metals can be extracted from the ash. Copper ions are then leached from the ash by adding sulphuric acid making a solution of copper sulphate. Displacement is used with iron as well as electrolysis to gain pure copper.