1.3 Metals And Their Uses Flashcards
Displacement reactions
A more reactive metal will displace a less reactive metal from a compound
E.g
Iron + copper sulfate 👉 iron sulfate + copper
Raw materials which go into a blast furnace…
Iron ore= iron 111 oxide Fe2O3
Coke= carbon C
Limestone= CaCO3
Reduction
Removal of oxygen from a substance.
What is the overall equation for a blast furnace?
Iron oxide + carbon👉 iron + carbon dioxide
2Fe2O3 + 3C 👉 4Fe + 3CO2
What stages are there of the reduction of the iron oxide? ( the carbon has reduced the iron oxide to iron)
1.Carbon burns
C + O 👉 CO2
- Carbon dioxide reacts with more carbon
CO2 + C 👉2CO - Carbon monoxide reduces the iron oxide
3CO + Fe2O3 👉 2Fe + 3CO2 - Limestone added to remove impurities (SiO2)
CaCO3 👉 CaO + CO2
CaO + SiO2 👉 CaSiO3 (calcium silicate-slag)
Blast furnace?
Charge mixture at the top, lever moved down to let more in. Waste gases mostly CO2 com out top right. 400 degrees Celsius at top. Charge reaction takes place in between. 1800 degrees Celsius at bottom. Hot air blasted in form bottom sides. Slag comes out left at bottom. Molten iron comes out right at bottom.
Pure iron composition?
100% Fe
Pure iron properties and uses?
Very soft and easily shaped.
Too soft for most uses.
Cast iron(aka pig iron) is made…
And taken straight from the blast furnace.
Cast iron composition?
96% iron Contains impurities (mainly carbon)
Cast iron properties and uses?
Very brittle and hard, cannot be easily compressed. Wood-burning stoves. Man-hole covers. Engines Railings Fire Places
Carbon steels are made…
By alloying iron with small amounts of carbon. These are the cheapest steels to make.
Carbon steels- high carbon steel composition?
0.03% to 1.5% of carbon
~98.5% iron
Carbon steels- low carbon steel- mild steel composition?
Less than 0.1% carbon.
~99.9% iron.
Carbon steels- high carbon steel properties and uses?
Very strong and brittle. Bodies of cars. Knives. Ships containers. Machinery. Structural steel for building bridges.
Carbon steels- low carbon steel- mild steel properties and uses?
Soft and easily shaped, not as strong as high carbon steel, but less likely to shatter.
Useful in Mass production, such as making bodies of cars.
Alloy steels are made…
Of alloys of steel and other metals.
They are more expensive than carbon steels.
Low alloy steels contain between 1% to 5% other metals.
High alloy steels have a greater percentage of other metals.
Nickel steel alloys (low alloy steel) composition?
~ 1% to 5% other metals
~ 99%-95% iron
Tungsten steel (low alloy steel) composition?
~ 1% to 5% other metals
~ 99%-95% iron
Stainless steel (high alloy steel) composition?
75% iron
10% nickel
Higher percentage of other metals e.g chromium steels 12%-15% chromium
Nickel steel (low alloy steel) properties and uses?
Very resistant to stretching forces, hard and strong. Build long span bridges. Bicycle chains Military armour-plating Tools
Tungsten steel (low alloy steel) properties and uses?
Operates well under very hot conditions, hard and string and high melting point.
Used to make high-speed tools (drill bits, cutting blades.)