Karteikarten
Chemistry 1
Karten in diesem Stapel (27)
- 1What 2 factors does the extraction of metal depend on?-How easy it is to extract from its ore
-How much metal an ore contains - 2Where do metals come from?They are found in the earths crust and most are found chemically combined with other elements (often oxygen).
- 3What is an Ore?A Rock containing enough of a metal to make it worth extracting.
- 4What do we call the removal of oxygen from a compound?Reduction
- 5What does it mean when we say that certain metals are found in their native state?The metals are so unreactive (eg gold and silver) that they are found in the Earth already as the metal elements themselves - so no extraction is needed.
- 6What can displace less reactive metals from their compounds?More reactive metals
- 7Why can carbon be used to displace some metals from their ores?Because it is more reactive than a lot of metals and can be used to displace them from their oxides.
- 8How are metals that are more reactive than carbon extracted?Electrolysis
- 9Where is iron extracted from its ore ( iron oxide)?In a blast furnace
- 10What is cast iron?Iron that is formed in a blast furnace that contains 96% iron and impurities (mainly carbon) which makes it very brittle but it is also hard and not easily compressed.
- 11Once all the carbon and impurities are removed from the iron, What is it like?Very soft and malleable; too soft for most uses unfortunately.
- 12How do we make iron more useful?Combine it with other elements to make it stronger eg to make steel.
- 13What do we call a metal that's been mixed with other elements?An alloy
- 14What are the simplest steels and how are they made?Carbon steels; remove most of the carbon from cast iron leaving just small amounts of carbon.
- 15What are carbon steels used for?Bodies of cars, knives, machinery, ships, containers and structural steel for buildings.
- 16What is more expensive low-alloy steels are carbon steels?Low alloy steels because they contain 1-5% of other metals.
- 17What are stainless steels used for and why are they good?Cooking utensils and cutlery and in a reaction to make vessels because they combine hardness and strength with great resistance to corrosion.
- 18Which two metals are often used when we require a metal that is strong with a low density.Aluminium and Titanium
- 19What does Aluminium resist corrosion?Because the Al atoms at its surface react with O2 in the air to form a thin AlO layer which stops any further corrosion.
- 20What are aluminium alloys like?Harder, more rigid and stronger than our Al.
- 21What can we use aluminium for?Drinks cans, cooking foil, saucepans, high voltage electricity cables, aeroplanes and space vehicles and bicycles.
- 22How is aluminium extracted?By electrolysis as it is more reactive than carbon.
- 23What are the steps of Aluminium extraction?1. Mine the ore which contains AlO and other impurities.
2. AlO is separated from impurities.
3. Oxides are melted (which requires a very high temp) before electrolysis can occur. - 24What are the properties of Titanium?Silvery-White metal; very strong and very resistant to corrosion (due to similar oxide layer as Al); denser than Al but not overly dense; high melting point (1660degrees).
- 25What is Titanium used for?Bodies of high performance aircraft; parts of jet engines; parts of nuclear reactors; replacement hip joints.
- 26How can Titanium be extracted?Displacement from oxides as its nor very reactive. But not by carbon as they react together, instead it is displaced by Na or Mg which are more reactive (however Na and Mg have to be electrolysed beforehand so this is expensive).
- 27What are the steps of extracting Titanium?1. Titanium ore must be processed.
2. Titanium ore is separated converting it to chloride.
3. Chloride is distilled to purify it.
4. Then Titanium can be displaced by Na or Mg.
Informationen
- Beschreibung
- Metals
- Erstellt von
- phoebeolivia
- Aufrufe
- 0
- Bewertung
Mehr zu Metal Extraction Methods