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GCSE Core Chemistry Exam tip; You Exam tip; You DO DO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they contain contain

Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

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Properties of iron & steels. Prior Learning: Identify & explain different extraction processes. Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels. Learning Objectives: By the end of the lesson I can:. • The properties of pig iron and how this limits its usefulness. - PowerPoint PPT Presentation

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Page 1: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Page 2: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

KeywordsKeywords:: Alloy, carbon steels, low-alloy steels, high-alloy Alloy, carbon steels, low-alloy steels, high-alloy steelssteels

Prior Learning:Prior Learning:Identify & explain different extraction processesIdentify & explain different extraction processes

Page 3: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainLearning Objectives: By the end of the lesson I can: • • The properties of pig iron and how this limits its usefulness.The properties of pig iron and how this limits its usefulness.Pig iron is the intermediate product of smelting iron ore with Pig iron is the intermediate product of smelting iron ore with coke. Pig iron has a very high carbon content, typically 3.5–coke. Pig iron has a very high carbon content, typically 3.5–4.5%, which makes it very brittle and not useful directly as a 4.5%, which makes it very brittle and not useful directly as a material except for limited applications.material except for limited applications.• • That iron can be alloyed to make it more useful.That iron can be alloyed to make it more useful.

• • Explain how the properties of alloys (but not smart alloys) Explain how the properties of alloys (but not smart alloys) are related to models of their structures.are related to models of their structures.

Page 4: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainWhat are the properties of different metals?

Page 5: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain• gold (Au): This metal is unreactive. This is represented by having the band on stage, not mixing with the other elements and not doing very much.

• lead (Pb), zinc (Zn) and copper (Cu): These metals are heavy metals and are dressed up as heavy metal rockers.

• copper (Cu): This metal has been drawn into wires. • aluminium (Al) and titanium (Ti): These metals are reactive.

In this scene, they are getting overexcited and knocking over a table.

• iron (Fe): This metal has rust patches and is struggling to lift the bar stools.

• steel (Fe wearing ‘nerves of steel’ T shirts): These metal alloys have carbon atoms on their shoulders to show that they are alloys. The steel is shinier than the iron atom. Steel is easily lifting the bar stools that iron was unable to lift because it is stronger.

Page 6: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainLet’s go back in time 3 years to

Year 7YEAR 10YEAR 10

YEAR 7YEAR 7

And draw (or make a

model to show) the

atom arrangement

in a solid

Now add a different

sized particle to your

model. What is this

called?

Page 7: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainWhat are the general properties of most metals?

solid at room temperature

Why do metals have these particular properties?

high melting point good conductors of electricity and heat malleable: they can be shaped ductile: they can be drawn into wires strong dense

Page 8: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainsea of electrons

metal ions

The atoms in a pure metal are in tightly-packed layers, which form a regular lattice structure.

The outer electrons of the metal atoms separate from the atoms and create a ‘sea of electrons’.

These electrons are delocalized and so are free to move through the whole structure.

The metal atoms become positively charged ions and are attracted to the sea of electrons. This attraction is called metallic bonding.

Page 9: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainHow does the sea of electrons affect the properties of metals?

Page 10: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainDelocalized electrons in metallic bonding allow metals to conduct heat and electricity.

This makes heat transfer in metals very efficient. Delocalized electrons also conduct electricity through metals in a similar way.

For example, when a metal is heated, the delocalized electrons gain kinetic energy.These electrons then move faster and so transfer the gained energy throughout the metal.

heat

Page 11: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainMetals are usually strong, not brittle. When a metal is hit, the layers of metal ions are able to slide over each other, and so the structure does not shatter.

The metallic bonds do not break because the delocalized electrons are free to move throughout the structure.

metal after it is hit

forceforce

This also explains why metals are malleable (easy to shape) and ductile (can be drawn into wires).

metal before it is hit

Page 12: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Page 13: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainInvestigating Alloys

How would you investigate the strength of alloy How would you investigate the strength of alloy wires?wires?

What will you change? (The independent variable)What will you change? (The independent variable)

What will you measure? (The dependent variable)What will you measure? (The dependent variable)

How would you make it a fair test? (Controlled How would you make it a fair test? (Controlled variables)variables)

Page 14: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

On a plain piece of paper add information from the following slides to create a mind map on iron including;

• Alloying• Extraction• Properties• Chemical information• (Anything else you wish to include)

Page 15: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Most iron is converted into steels.

Removing all impurities would produce pure iron. Pure iron has a regular arrangement of atoms, with layers that can slide over each other, and so is soft and easily shaped, but too soft for many uses.

The iron collected from a blast furnace is only 96% pure.

molten iron

hot air

molten slag

raw materialsUsually, this product will be treated further because the impurities make iron brittle.

Page 16: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainSteel is an alloy of iron and other elements, including carbon, nickel and chromium.

Steel is stronger than pure iron and can be used for everything from sauce pans… …to suspension bridges!

Page 17: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

The atoms of other elements are different sizes. When other elements are added to iron, their atoms distort the regular structure of the iron atoms.

The atoms in pure iron are arranged in densely-packed layers. These layers can slide over each other. This makes pure iron a very soft material.

It is more difficult for the layers of iron atoms in steel to slide over each other and so this alloy is stronger than pure iron.

Page 18: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainOVERVIEW - Steel

Steels are alloys, since they are mixtures of Steels are alloys, since they are mixtures of iron with carbon and other metals.iron with carbon and other metals. The The different sized atoms distort the layers in different sized atoms distort the layers in the structure of the pure metal, making it the structure of the pure metal, making it more difficult for them to slide over each more difficult for them to slide over each other, and so alloys are harder.other, and so alloys are harder. Alloys can Alloys can be designed to have properties for specific be designed to have properties for specific uses.uses. Low carbon steelsLow carbon steels are easily shaped, are easily shaped, high carbon steelshigh carbon steels are hard, and are hard, and stainless stainless steelssteels are resistant to corrosion. are resistant to corrosion.

Page 19: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainSteel is not a single substance & there are lots of different steels all being an alloy of iron with either carbon and/or other elements.

low carbon steel contains less than 0.25% carbon

Soft and easily shaped. Not as strong as high carbon steel but less likely to shatter. high carbon steel contains more than 0.5% carbon.

Very strong but brittle.

1. CARBON STEEL: made by alloying Fe with small amounts of C (from 0.03-1.5%). They are the cheapest to make & are used for car bodies, knives, ships, machinery, containers, structural steel for buildings.

Page 20: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Nickel-steel very resistant to stretching forces so are used for long-span bridges, military armour-plating

Tungsten-steel operates well under very hot conditions so it is used to make high-speed tools.

2. LOW-ALLOY STEEL: made by alloying Fe with small amounts of other metals (from 1-5%). They are more expensive & may contain metals like Ni, Cr, Mn, V Ti and W. Each giving a different property.

Page 21: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Chromium-steel strong with chemical stability it is mixed with between 12-15% Cr and often some Ni

This is also known as ‘stainless steel’ These are used to make cooking utensils & cutlery, chemical reaction vessels because they combine hardness & strength with a resistance to corrosion (they do not rust!)

3. HIGH-ALLOY STEEL: made by alloying Fe with large amounts of other metals. They are EVEN more expensive & may contain metals like Ni, Cr, Mn, V Ti and W. Each giving a different property.

Page 22: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Page 23: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontain

Page 24: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainRef’s DecisionRef’s Decision

If its true it stays, if its false SEND IT OFF!

Yellow = TRUEYellow = TRUE, Blue = FALSEBlue = FALSE

Steel is a mixtureSteel is a mixtureAll steels contain cobalt (Co)All steels contain cobalt (Co)

Stainless steels are expensiveStainless steels are expensiveStainless steels rust because Stainless steels rust because they contain ironthey contain iron

The molecular formula for The molecular formula for steel is Ststeel is St

Page 25: Keywords : Alloy, carbon steels, low-alloy steels, high-alloy steels

GCSE Core Chemistry

Exam tip; You Exam tip; You DODO need to know the 3 main types of steel need to know the 3 main types of steel (carbon, low-alloy & high-alloy) & identify what they (carbon, low-alloy & high-alloy) & identify what they

containcontainLearning Objectives: By the end of the lesson I can: • • The properties of pig iron and how this limits its usefulness.The properties of pig iron and how this limits its usefulness.Pig iron is the intermediate product of smelting iron ore with Pig iron is the intermediate product of smelting iron ore with coke. Pig iron has a very high carbon content, typically 3.5–coke. Pig iron has a very high carbon content, typically 3.5–4.5%, which makes it very brittle and not useful directly as a 4.5%, which makes it very brittle and not useful directly as a material except for limited applications.material except for limited applications.• • That iron can be alloyed to make it more useful.That iron can be alloyed to make it more useful.

• • Explain how the properties of alloys (but not smart alloys) Explain how the properties of alloys (but not smart alloys) are related to models of their structures.are related to models of their structures.