chemistry unit 1 (1)

8/22/2019 Chemistry Unit 1 (1)

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04/08/2013

Chemistry Unit 1

AQA

W Richards
mailto:[email protected]:[email protected]


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The structure of the atom

ELECTRON

negative, massnearly nothing

PROTON positive, same

mass asneutron (1)

NEUTRON neutral, same

mass asproton (1)

The Ancient Greeks used to believe that

everything was made up of very small particles. Idid some experiments in 1808 that proved thisand called these particles ATOMS:

Dalton


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Mass and atomic number

Particle Relative Mass Relative Charge

Proton 1 +1

Neutron 1 0

Electron Very small -1

MASS NUMBER = number ofprotons + number of neutrons

SYMBOL

PROTON NUMBER = number of

protons (obviously)


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04/08/2013

Mass and atomic numberHow many protons, neutrons and electrons?


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04/08/2013Electron structure

Consider an atom of Potassium:

Potassium has 19 electrons.These electrons occupyspecific energy levelsshells

Nucleus

The inner shell has __ electrons

The next shell has __ electrons

The next shell has __ electrons

The next shell has the remaining __ electron

Electron structure

= 2,8,8,1


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04/08/2013Electron structure

Draw the electronic structure of the following atoms:

Electron structure

= 2,8,8,2

Nucleus

Electron structure

= 2,8,2

Nucleus

Electron structure

= 2,5

Nucleus


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04/08/2013Periodic Table IntroductionHow would you arrange these elements into groups?
http://localhost/var/www/apps/conversion/tmp/scratch_7/rates%20of%20reaction.exe


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Mendeleev

Periodic table

The periodic table arranges all the elements

in groups according to their properties.

Horizontal rows are called PERIODS

Vertical

columns arecalled GROUPS


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H He

Li Be B C N O F Ne

Na Mg Al Si P S Cl Ar

K Ca Fe Ni Cu Zn Br Kr

Ag I Xe

Pt Au Hg

The Periodic TableFact 1: Elements in the same group have the

same number of electrons in the outer shell (thiscorresponds to their group number)

E.g. all group 1 metals

have __ electron intheir outer shell

These elements

have __ electronsin their outer shell

These elements have

__ electrons in theirouter shells


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H He

Li Be B C N O F Ne



Ag I Xe

Pt Au Hg

The Periodic TableFact 2: As you move down through the periods an

extra electron shell is added:

E.g. Lithium has 3electron in theconfiguration 2,1

Potassium has 19 electrons in

the configuration __,__,__,__

Sodium has 11electrons in the

configuration 2,8,1


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H He

Li Be B C N O F Ne



Ag I Xe

Pt Au Hg

The Periodic TableFact 3: Most of the elements are metals:

These elementsare metals

This line divides

metals from non-metals

These elements are

non-metals


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H He

Li Be B C N O F Ne



Ag I Xe

Pt Au Hg

The Periodic TableFact 4: (Most important) All of the elements in

the same group have similar PROPERTIES. Thisis how I thought of the periodic table in the firstplace. This is called PERIODICITY.

E.g. consider the group 1 metals. They all:

1) Are soft

2) Can be easily cut with a knife

3) React with water

4/ / 1


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04/08/2013Group 1 The alkali metals

Li

Na

K

Rb

Cs

Fr

Watch video of thesemetals reacting with water(from Sky Ones Brainiac)

04/08/2013
http://www.youtube.com/watch?v=m55kgyApYrYhttp://www.youtube.com/watch?v=m55kgyApYrYhttp://www.youtube.com/watch?v=m55kgyApYrYhttp://www.youtube.com/watch?v=m55kgyApYrYhttp://www.youtube.com/watch?v=m55kgyApYrYhttp://www.youtube.com/watch?v=m55kgyApYrY


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04/08/2013Group 0 The Noble gases

He

Ne

Ar

Kr

Xe

Rn

Questions:

1) How many electrons do these elements havein their outer shell?

2) How does this affect their reactivity?

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CompoundsCompounds are formedwhen two or moreelements arechemically combinedby sharing or giving ofelectrons. Some

examples:

Glucose

Methane

Sodiumchloride (salt)

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Some simple compounds

Methane, CH4 Water, H2O

Carbondioxide, CO2

Ethyne, C2H2sulfuric acid,

H2SO4

Key

Hydrogen

Oxygen

Carbon

sulfur

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04/08/2013Bonding introduced

Hi. My names Johnny Chlorine.Im in Group 7, so I have 7

electrons in my outer shell

Id quite like to have a full outershell. To do this I need to GAINan electron. Who can help me?

Cl

Cl

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04/08/2013Bonding

Here comes one of my friends, HarryHydrogen

Hey Johnny. Ive only got one

electron but its really close to mynucleus so I dont want to lose it.

Fancy sharing?

Cl

H

Cl H

Now were both really stable.Weve formed a covalent bond.

04/08/2013d


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04/08/2013Bonding

Here comes another friend, Sophie

Sodium

Hey Johnny. Im in Group 1 so I haveone electron in my outer shell. UnlikeHarry, this electron is far away from

the nucleus so Im quite happy to getrid of it. Do you want it?

Cl

Now weve both got full outer shellsand weve both gained a charge.

Were both called IONS and weve

formed an IONIC bond.

Na

Okay

Cl Na

+-

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B l


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04/08/2013Balancing equations

Consider the following reaction:

Na O

H HH HNa

OH

Sodium + water sodium hydroxide + hydrogen

+ +

This equation doesnt balance there are 2 hydrogenatoms on the left hand side (the reactants and 3 onthe right hand side (the products)

04/08/2013

B l


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04/08/2013Balancing equations

We need to balance the equation:

NaO

H H

H H

Na

OH

Sodium + water sodium hydroxide + hydrogen

+ +

Na

O

H H

Na

OH

Now the equation is balanced, and we can write it as:

2Na(s) + 2H2O(l) 2NaOH(aq) + H2(g)

04/08/2013l


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04/08/2013Some examples

Mg + O2

Zn + HCl

Fe + Cl2

NaOH + HCl

CH4 + O2

Ca + H2O

NaOH + H2SO4

CH3OH + O2

MgOZnCl2 + H2

FeCl3

NaCl + H2O

CO2 + H2O

Ca(OH)2 + H2

Na2SO4 + H2O

CO2 + H2O

22

2 3

2

2

2

2 3

2

2

2

2

2 4

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f


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04/08/2013Conservation of mass in reactions

In any reaction the total mass of products isthe same as the total mass of the reactants

Example 1Magnesium oxide and hydrochloric acid

MgO

H Cl

MgCl

Cl

H

H

OH Cl

1 x magnesium, 1 x oxygen, 2 xhydrogen and 2 x chlorine atoms

Also 1 x magnesium, 1 x oxygen, 2x hydrogen and 2 x chlorine atoms

C

H

H

H

HO

O

OO

OH H

OH H

CO

O

Example 2Burning methane

04/08/2013Li


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04/08/2013Limestone

Limestone is a rock made up of mainly calciumcarbonate. Its cheap and easy to obtain. Some

uses:

1) Building materials limestone can be ______and cut into blocks to be used in _______.However, it is badly affected by ____ ____.

2) Cement making limestone can be

roasted

in a rotary kilnto produce dry cement. Its then mixed with sand and _____to make _______.

View video of limestone being quarried

Words building, quarried, gravel, concrete, acid rain

04/08/2013Li
http://www.youtube.com/watch?v=VlLKQncIl6Ehttp://www.youtube.com/watch?v=VlLKQncIl6E


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04/08/2013Limestone

If soil is too _____ crops will fail. Limestone can also be usedas a neutralising agent. There are two reactions to know:

1) Firstly, a THERMAL _________________ reaction is usedto break the calcium carbonate down into calcium oxide and

_______ __________:

2) This is then slaked with water to produce calciumhydroxide:

Calcium hydroxide is alkaline and is used to ______ acidic soil.

Calcium carbonate calcium oxide + carbon dioxideHEAT

Calcium oxide calcium hydroxideWATER

Words acidic, neutralise, decomposition,

carbon dioxide

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Th

Li C l


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04/08/2013

The Limestone Cycle

Calcium Carbonate

(limestone)

Calcium Oxide

Calcium Hydroxide

Step 1:heat

Step 2:add a littlewater

Step 3: addmore waterand filter

Step 4:add CO2

CO2

Calcium Hydroxide solution

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Th l d i i f b


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04/08/2013Thermal decomposition of carbonates

Limestone undergoes thermal decomposition when heated. Thesame happens to other carbonates. For example, consider

copper carbonate:

Limewater

Copper carbonate(green) turns intocopper oxide (black)

Limewater goescloudy due to carbondioxide being made

Copper carbonate copper oxide + carbon dioxide

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Th P i di T bl


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H He

Li Be B C N O F Ne



Ag I Xe

Pt Au Hg

The Periodic TableRecall something we said earlier some of the

elements are metals:These elementsare metals

This line dividesmetals from non-metals

These elements are

non-metals

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Properties of metals

Metals have very high melting points (which means that they are usually

_____) whereas non-metals will melt at lower ___________All metals conduct heat and __________ very well, whereas non-metalsdont (usually)

Metals are strong and ______ but bendable. Non-metals are usually

_____ or they will snap.Metals will _____ when freshly cut or scratched, whereas non-metals areusually dull.

Metals have higher _______ than non-metals (i.e. they weigh more)

Metals can be used to make ______ (a mixture of different metals)Words - alloys, electricity, solids, weak, densities,

temperatures, tough, shine

04/08/2013E t ti M t l


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04/08/2013Extracting Metals

A METAL ORE is a mineral or mixture ofminerals from which it is economicallyviable to extract some metal.

To extract a metal from a metal oxide we need to REDUCE

the oxygen. This is called a REDUCTION reaction. To put itsimply:

Most ores contain METAL OXIDES (e.g. rust = iron oxide).

Some definitions:

Iron OxideIronore

Reduce the oxygento make iron

04/08/2013How do we do it?


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OxideIron

How do we do it?Potassium

Sodium

Calcium

Magnesium

Aluminium

Carbon

Zinc

Iron

Tin

LeadCopper

Silver

Gold

Platinum

Metals ABOVE CARBON, becauseof their high reactivity, are

extracted by ELECTROLYSIS,which is very expensive!

Metals BELOW CARBON areextracted by heating them withcarbon in a BLAST FURNACE.This is a displacement reaction

These LOW REACTIVITY metalswont need to be extracted becausethey are SO unreactive youll find

them on their own, not in a metal oxide

Carbon

04/08/2013E t ti t l


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04/08/2013Extracting metals

1) What is an ore?

2) In what form are metals usually found in the Earth?

3) How do you get a metal out of a metal oxide?

4) What is this type of reaction called?

Type of metal Extraction process Examples

High reactivity (i.e anythingabove carbon)

Middle reactivity (i.e.anything below carbon)

Low reactivity

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Th T iti M t l


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04/08/2013The Transition Metals

1) This section includes metals like gold, mercury, iron, copper

Somefacts

2) They are all ______ and solid (except _________)

3) They are ____ reactive than the alkali metals

Words hard, coloured, mercury, less, catalyst, insoluble

4) They can form __________ compounds, usually _______5) They can be used as a ______ (a chemical that speeds up areaction)

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C Al i i d Tit i


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/ /Copper, Aluminium and Titanium

Metal Uses and why Extraction method Problems

Copper Electrical wires good conductor

Electrolysis Limited supply

Aluminium andtitanium

Planes light andcorrrosionresistant

Complicated andexpensive

Expensive anddifficult to extract

Supplies of any raw material are limited so what are the

options?

04/08/2013U in I n


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Using Iron

Iron produced by the blast furnace (cast iron) contains

about 96% iron and 4% impurities. These impurities make itvery brittle and easy to break.

Ironbridge, Shropshire made out of cast ironand safe for horses and

carts but not modernvehicles.

04/08/2013Usin Ir n


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Using Iron

In pure iron all

impurities areremoved. Thismakes the iron soft:

Adding 1% impuritiesmakes the iron muchstronger:

04/08/2013M kin st l


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Making steel

Amount ofcarbon

added (%)0.5% 1%

Strong

Weak

1.5%

Strength

Hardness

Steel with a lowcarbon content iseasily shaped

Steel with a highcarbon content isstrong but brittle

Steel with chromiumand nickel is calledstainless steel

04/08/2013Alloys
http://www.bbc.co.uk/london/whereyoulive/west/hounslow/eating.shtml


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AlloysSteel is an alloy i.e. a mixture of metals. Here are otheralloys:

Gold mixed with

copper

Aluminium mixed

with magnesiumand copper

Aluminiun mixed

with chromium

04/08/2013Electrolysis


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Electrolysis

+++

+

---

-

Positive

electrode

Cu2+

Cu2+

Cu2+

Negative

electrode

Cl-

Cl-

Cl-

Solution

containingcopper andchloride ions

04/08/2013Electrolysis


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Electrolysis

Electrolysis is used to separate a metal from its compound.

= chloride ion

= copper ion

When we electrolysedcopper chloride the _____chloride ions moved to the

______ electrode and the______ copper ions movedto the ______ electrodeOPPOSITES ATTRACT!!!

Extracting and purifying copper04/08/2013


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Extracting and purifying copperCopper can be extracted from copper-rich ores by heating theores in a furnace and then purifying it by electrolysis.

Extracting copperuses large amounts of

heat and energy

Bingham Canyon coppermine in Utah, one of the

largest in the world

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Purifying Copper by electrolysis


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Purifying Copper by electrolysis

+++

+

---

-

Solution

containingcopper ions

Impure

copper

Cu2+

Cu2+

Cu2+

Pure copper

New ways of extracting copper04/08/2013


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New ways of extracting copper

Mining lower-grade ____

Phytomining growing_____ that absorb metals

and then ______ them toextract the metal from __.

Bioleaching using ______ toproduce leachate solutions thatcontain metal _________.

Words compounds, plants, ores, bacteria, burning, ash

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Extracting Aluminium


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Extracting Aluminium

Aluminium has to be extracted from its ore by electrolysis. This isbecause aluminium is very ___________ and so it cannot be extracted

using ______. The amount of energy and _____ required to extractaluminium and other metals is very high and so ________ is a muchbetter option.

Words reactive, recycling, money, carbon

Extracting metals from soil04/08/2013


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Extracting metals from soil

Where metals have

contaminated land (e.g.brown field sites), plantssuch as brassica can be usedto extract the metals back

out of the soil and the metalscan then be recovered fromthe plants.

04/08/2013Crude Oil


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Crude Oil

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Hydrocarbons and crude oil


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Hydrocarbons and crude oil

Longer chains mean

1. Less ability to flow

2. Less flammable

3. Less volatile

4. Higher boiling point

In

creasing

le

ngth

Crude oil is a mixture of HYDROCARBONS

(compounds made up of carbon and hydrogen).Some examples:

Ethane

C C

HH

H

HH

H

Butane

C CHH H

HH

H C C HH

HH

04/08/2013Distillation rev

ision


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Distillation revision

This apparatus can be used to

separate water and inkbecause they have different

_____ ______. The ______will evaporate first, turn backinto a _______ in the

condenser and collect in the_______. The ink remains inthe round flask, as long as the

_______ does not exceedinks boiling point. This

method can be used toseparate crude oil.

Words temperature, boiling points, water, beaker, liquid

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Fractional distillation


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Fractional distillationCrude oil can be separated by fractional distillation. The oil is evaporatedand the hydrocarbon chains of different lengths condense at differenttemperatures:

Fractions withlow boilingpoints condense

at the top

Fractions withhigh boilingpoints condenseat the bottom

04/08/2013Alkanes


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AlkanesAlkanes are SATURATED HYDROCARBONS. What does thismean?

HYDROCARBONS are molecules that are made up ofhydrogen and carbon atoms

SATURATED means that all of these atoms are held

together by single COVALENT bonds, for example:

Ethane

Alkanes are fairly unreactive (but they do burn well). The

general formula for an alkane is CnH2n+2

C C

HH

H

HH

H

Butane

C C

HH H

HH

H C C H

H

HH

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General Formulae for Alkanes


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General Formulae for AlkanesInstead of circles, lets use letters

General formula for alkanes = CnH2n+2

Butane (n=4)

H

C C

H

HH

H

C C

H

HH

H H

Methane (n=1)

H

C H

H

H

Ethane (n=2)

H

H

C C

H

HH

H

Propane (n=3)

H

C H

H

H

C C

H

HH

H

04/08/2013Burning Fossil

Fuels


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Burning Fossil FuelsBurning fossil fuels like oil and coal causes pollution.

Oil contains carbon:

C

H

H

H

HO

O

OO

OH H

OH H

CO

O

Carbon dioxide is a greenhousegas it helps cause global warming

Coal contains carbon, sulfur and other particles:sulfur + oxygen sulfur dioxide

Sulfur dioxide causes acid rain. Other particles cancause global dimming sunlight is absorbed by the

particles in the atmosphere.

04/08/2013Removing Sulfur 04/08/2013


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Removing SulfurSulfur dioxide is clearly bad for the environment so its a goodidea to remove as much sulfur as possible:

Vehicles can remove sulfurfrom fuels before theyare burned.

Power stations can removesulfur dioxide from wastegases after combustion.

04/08/2013Other fuel sources


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Other fuel sources

Task: Identify two other fuel sources (biofuels) currently

being developed and find out the following:

1) What is the source called and what is it made of?

2) Why is the fuel better than coal?

3) What are the disadvantages of this fuel?

04/08/2013Using Crude Oil


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Using Crude Oil

Crude Oil

Benefits Drawbacks

Cheap toextract

Wide range ofuses as fuel

Used to makeplastics

Plastics dontbiodegrade

Burning

fossil fuelscauses

pollution

Disposal ofmaterials

uses up landfill sites

Itsgoing torun out

04/08/2013Disposal

of plastics


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Disposal of plastics1) Landfill sites - most plastics do not

_________ which means that landfill sitesare quickly filled up. Research is beingcarried out on __________ plastics.

2) Burning this releases carbon

dioxide which causes the________ effect, as well asother ________ gases.

3) _______ the best option, butdifficult because of the differenttypes of plastic

Words recycling, greenhouse,

decompose, biodegradable, poisonous

04/08/2013Ethanol


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EthanolEthanol is an important chemical. Many

countries are increasing the amount ofethanol put into their petrol supplies:

Ethanol is a clean burning energy source and produces littleor no greenhouse gases. How is it made and what are the

advantages and disadvanatges of each method?

Ford Escape E85 runs on 85% ethanol

The fossil fuel way

The renewable way

Ethene + steam ethanolEthene is produced bycracking oil

Sugar ethanol + carbon dioxide

Sugar is produced fromstandard crops like

sugar cane and corn

04/08/2013

Making ethanol from ethene


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Making ethanol from ethene

Ethene

Reaction vessel with hightemperature and pressure

and a catalyst Ethanol

Unused ethene recycled

Ethene + water ethanol

C2H + H20 C2H5OH

04/08/2013Cracking


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CrackingShorter chain hydrocarbons are in greater demand becausethey burn easier. They can be made from long chain

hydrocarbons bycracking

:

Butane

Ethane

For example, this bondcan be cracked togive these:

Ethene

04/08/2013Cracking


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Cracking

This is a THERMAL DECOMPOSITION reaction,with clay used as a catalyst

1) Carbon dioxide causes the _________ effect

2) Sulfur dioxide causes _____ _____

3) Plastics are not _____________

Cracking is used to produce plastics such as polymers and polyethanes. The

waste products from this reaction include carbon dioxide, sulfur dioxideand water vapour. There are three main environmental problems here:

Long chainhydrocarbon

Heatedcatalyst

Gaseoushydrocarbon

Liquid

hydrocarbon

04/08/2013Alkenes


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AlkenesAlkenes are different to alkanes; they contain DOUBLECOVALENT bonds. For example:

Ethane Ethene

Butane Butene

This double bond means that alkenes have the potential to joinwith other molecules this make them REACTIVE. Alkenes

turn bromine water colourless.

ALKANES

ALKENES

Testing for alkenes 04/08/2013


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Testing for alkenes

Oil Bromine goescolourless

Brominewater

04/08/2013

General Formulae for Alkenes


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General Formulae for Alkenes

General formula for alkenes = CnH2n

Propene (n=3)

H

C H

H

H

C C

H

H

Ethene (n=2)

H

H

C C

H

H

Butene (n=4)

H

C C

H

HH

H

C C

H

H H

04/08/2013

Monomers and Polymers


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Monomers and Polymers

C CHH

HH

Ethene

Heres ethene again. Ethene is called aMONOMER because it is just one smallmolecule. We can use ethene to makeplastics

Step 1: Break the double bond

Step 2: Addthe molecules

together:

This molecule is called POLYETHENE,and the process that made it is called

POLYMERISATION

04/08/2013

Another way of drawing it


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Another way of drawing itInstead of circles, lets use letters

Ethene

C C

HH

HH

C C

HH

HH

Ethene

H

C C

H

HH

H

C C

H

HH

Poly(e)thene

General formula for addition polymerisation:

C Cn C C

n

e.g. C Cn

H CH3

HH

C C

n

H CH3

HH

04/08/2013Some examples


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Some examples

C C n

H H

HH

C Cn

H H

HCl

C Cn

H H

HH

C CnH H

HCl

C CnH Cl

HBr

C Cn

H Cl

HBr

04/08/2013

Uses of addition polymers


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Uses of addition polymersPoly(ethene) Poly(propene)

Poly(chloroethene), PVCPoly(styrene)

Biodegradable carrier bags04/08/2013
http://www.picsearch.com/info.cgi?q=guttering&cid=15840292808http://www.picsearch.com/info.cgi?q=pvc%20window&cid=593466145508http://www.picsearch.com/info.cgi?q=polystyrene&cid=638188450599&start=65http://www.picsearch.com/info.cgi?q=polystyrene&cid=829276250103http://www.picsearch.com/info.cgi?q=plastic%20chair&cid=216224297352http://www.picsearch.com/info.cgi?q=rope&cid=179471179647http://www.picsearch.com/info.cgi?q=car%20bumper&cid=651416074300http://www.picsearch.com/info.cgi?q=bleach%20bottle&cid=96274832671http://www.picsearch.com/info.cgi?q=plastic%20tub&cid=930236873411http://www.picsearch.com/info.cgi?q=carrier%20bag&cid=571236659116&start=65


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Biodegradable carrier bags

This carrier bag has been made with flax fibre fromindustrial waste.

04/08/2013

Measuring Energy in Food


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Measuring Energy in Food

The energy contentin foods is measured

in Joules and calories

Foods with large carbohydrate and fatcontents have lots of energy, but toomuch energy and too little exercise

could lead to obesity.

04/08/2013Vegetable Oils


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Vegetable O ls

Use of oil Benefits Drawbacks

Oily foods

Fuel

When plants photosynthesise they produce glucose. They canalso produce vegetable oils and we can use these for food and

fuel:

04/08/2013Extracting Oil


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E tract ng O

Step 1: Crush

the plant

Step 2: Remove oilby pressing

OR step 3: Removeoil by distillation

Why use oil for cooking?04/08/2013


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W y f g1) Why do we use oil for cooking and not just water?

2) What are the problems associated with using oil in cooking?

04/08/2013

Healthy and Unhealthy Oils


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y y

Unhealthy oils:

Healthy oils:

Saturated

Unsaturated

04/08/2013

Saturated vs. Unsaturated Fats


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Some oils are more healthy than others. Fish

oils contain the nutrients Omega-3 and Omega-6. These oils are unsaturated like ethene:

C C

HH

HH

Ethene

Testing for double bonds:

Clearly, it is important forscientists to be able to test if

a food contains healthyunsaturated fats orunhealthy saturated fats.Heres how its done:

Oil (in ethanol)Bromine goescolourless

Bromine

water

04/08/2013

Turning unsaturates into saturates


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g

The unsaturated fat is hardened byhydrogenation

.

Hydrogenated oils have a higher melting point and soare solid at room temperature, making them useful forspreads and pastries.

600C, Nickel catalyst

04/08/2013Emulsions


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Whats an emulsion?

Its a mixture of oil and

water, like in salad dressing

Paint is an emulsion. Other examples:

Milk Cream Butter

Butterfat

Watery liquid

04/08/2013

Why use emulsions?


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yEmulsions can have varying textures and this makes themuseful. Some examples:

Differentthicknesses

of cream

Paint andmayonnaise

04/08/2013Emulsifiers


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An emulsifier is an additive that will stop oiland water from seperating, like in mayonnaise.

How they work:

Water Oil

Im an emulsifier Illsort this out with my

hydrophobic end andmy hydrophilic end!I dont want tomix with you!

The water and oil drops become coated and insulated from

one another, which prevents them from seperating.

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Uses of emulsifiers in food


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Emulsifiers are used:

1) In bread, to stop large _____ developing when it bakes

2) In low fat spreads, to allow the oil and water to be _____

3) In ice cream and spray cream, to ______ the foam

4) In sponge cakes, to make tiny pockets of ____

5) In chocolate, to stop melted chocolate forming _______

Words crystals, air, holes, mixed, stabilise

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The Structure of the Earth


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A thin crust -10-100km thick

A mantle has theproperties of a solidbut it can also flow

A core made of

molten nickel and iron.Outer part is liquidand inner part is solid

The average density of the Earth is much higher than

the crust, so the inner core must be very dense

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Movement of the Lithosphere


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pThe Earths LITHOSPHERE (i.e. the _______) is splitup into different sections called ________ plates:

These plates are moving apart from each other afew centimetres every _______ due to the________ currents in the mantle caused by the________ decay of rocks inside the core.

Words radioactive, crust, convection, tectonic, year

04/08/2013Plate Movements


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Oceanic Crust

Mantle

Magma

Convection

Currents

Earthquakes andvolcanic eruptions can

be common here

04/08/2013The

Earths Atmosphere


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p

Carbon dioxide, water vapour Oxygen Nitrogen Noble gases

For the last 200 million years the atmosphere has remained roughly thesame it contains 78% nitrogen, 21% oxygen, 1% noble gases and about

0.03% CO2

04/08/2013Evolution of the E

arths Atmosphere


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4 Billion years 3 Billion years 2 Billion years 1 Billion years Present day

Carbon

dioxide

Methane Ammonia Oxygen Nitrogen Others

Present dayatmosphere contains78% nitrogen, 21%oxygen, 1% noblegases and about0.03% CO

2

04/08/2013Evolution of the E

arths Atmosphere


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4 Billion years 3 Billion years 2 Billion years 1 Billion years Present day

Volcanic activityreleases CO2, methane,ammonia and water

vapour into theatmosphere. The watervapour condenses toform oceans.

Some of the oxygen isconverted into ozone.

The ozone layer blocksout harmful ultra-violetrays which allows for thedevelopment of new life.

Green plants evolve which take in CO2 andgive out oxygen. Carbon from CO2

becomes locked up in sedimentary rocks ascarbonates and fossil fuels. Methane andammonia react with the oxygen andnitrogen is released.

One theory about how life was formed04/08/2013h d l h


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The Primordial Soup theory:

A collection ofsimple molecules

like methane

Amino acids

Dr StanleyMiller 1930-

2007

In 1953 I conducted an experiment thatproved that an electrical discharge can turnmethane into amino acids! This is called the

Miller-Urey experiment.

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Carbon dioxide in the atmosphereTh f CO h h ff d b 3 h


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The amount of CO2 in the atmosphere is affected by 3 things:

1) Geological activity moves carbonate rocks deep into

the Earth and they release ______ _______ into theatmosphere during volcanic activity.

2) When fossil fuels are burned the carboncontained in them reacts with _____ to form CO2.

3) Increased CO2 in the atmosphere causes a reactionbetween it and _______. These reactions do not remove ALLof the new CO2 so the greenhouse effect is still getting

_______!

Words oxygen, seawater, carbon dioxide, worse

04/08/2013Separating air


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p gAir can be separated into the different gases that make it up.To do this you first have to cool air down to -2000C and turn it

into a liquid:

Liquid air

(-200OC)Fractionaldistillation

In this chamber the air is gradually heated up again and

Nitrogen

Argon

Oxygen

RemoveCO2 and

H2O vapour

chemistry unit 1 (1)

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