Science Interactive LTD Copyright 2005
Science Interactive LTD
Science base multimedia CD-ROM for PC is a collection of 38 units or tools totalling over 1150
PowerPoint slides. Each unit covers a wide range of different delivery and learning styles, offering an
exciting way to involve your pupils during lessons or revision sessions. All styles of teaching and
learning are supported through use of high quality images, graphics, challenging exercises and
questions. Units can be used in the classroom via an interactive whiteboard, data projector or used
during individual study via a PC or school network.
Science Interactive LTD. PO BOX 50764 LONDON NW6 9AT email: sales@science-interactive.co.uk web: www:science-interactive.co.uk
Unit 1: The Digestive System Unit 20: Crude Oil and its Products
Unit 2: The Circulatory System Unit 21: Rock Cycle
Unit 3: Healthy Body and Immunity Unit 22: Elements, Molecules and Compounds
Unit 4: The Respiratory System Unit 23: Ionic and Covalent Compounds
Unit 5: Nervous System and the Senses Unit 24: The Halogens, their Uses and Compounds
Unit 6: Human Homeostasis Unit 25: The Noble Gases, their Properties and Uses
Unit 7: Hormones and the Endocrine System Unit 26: Rates of Reaction
Unit 8: Drugs and Bad Body Maintenance Unit 27: Energy
Unit 9: Photosynthesis in Green Plants Unit 28: Generating Electricity and its Domestic Use
Unit 10: Water Transport in Plants Unit 29: Electricity
Unit 11: Flow of Energy and Elements through the Environment Unit 30: Light and the Electromagnetic Spectrum
Unit 12: Mitosis and Meiosis Unit 31: Radioactivity
Unit 13: Inheritance and Selection Unit 32: Newton's Forces and the Effects of Forces
Unit 14: Evolution and Human Impact Unit 33: Earth and Space
Unit 15: Genetic Engineering Unit 34: The Earth and Plate Tectonics
Unit 16: The Periodic Table and its Elements Unit 35: The Alkaline Earth Metals
Unit 17: The Alkali Metals Unit 36: Sound and Hearing
Unit 18: Metals and their Properties Unit 37: Natural Forces
Unit 19: The Transitional Metals Unit 38: Cells, Tissue, Organs and Organs systems

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40
7 12 16
C O Ca
Li 6 8
3 20
3P+ Carbon Oxygen
6P+
Lithium Calcium
8P+ 20P+
4N 6N 8N 20N
3E- 6E-
8E- 20E-
Oxygen Water
Methane Nitrogen
Unit 22
Elements, Molecules and Compounds

Unit 22: Elements, Molecules and Compounds Science Interactive LTD Copyright 2005
Understand: Keywords:
That elements are pure substances, containing Element, Atoms, Particles, Protons, Neutron,
1.
only one type of atom. Electron, Periodic, Table, Groups, Periods,
That elements are arranged in the periodic table
2.
Materials, Molecules, Compounds, Orbital,
according to their atomic number giving rise to
Shells, Isotopes, Relative, Atomic, Mass,
eight distinct groups of elements with similar
Formula & Conservation.
physical and chemical properties.
The nature of sub atomic structure and that all
3.
atoms consist of protons, neutrons and
electrons.
The electronic configuration of the first 20
4.
elements.
The nature of materials and their properties.
5.
That molecules and compounds consists of
6.
two or more atoms of different or same
elements.
The relative formula mass of molecules and
7.
compounds.
That mass cannot be destroyed or created
8.
during chemical reactions.
Click mouse to begin
Science Interactive LTD PO BOX 50764 LONDON NW6 9AT web: www.science-interactive.co.uk email: sales@science-interactive.co.uk

Science Interactive LTD Copyright 2005
Understanding materials one
All materials, c___________ or chemicals are made from matter or atoms of
elements. There are just over 100 elements in the periodic table that combine together
in different ways to give rise to all the different types of materials that we use and see
every day. Some materials are extremely simple, containing only one or two different
e__________, where as others like biological molecules contain many different types
of elements. What is the definition of a pure substance ?
Materials and what they contain: Word bank: compounds elements
Sand Human Water Diamond
Diagram
Sand found on beaches Humans contain many Water, without which Diamond, the hardest
Notes
everywhere is made thousands of complex life would not exist is known substance is made
from two elements: molecules, made from made from two elements: from one type of
the following elements: element:
Hydrogen, Iron Oxygen
Silicon and Oxygen Hydrogen and Oxygen Carbon
Carbon, Nitrogen &
Phosphorus

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Understanding materials two
Atoms of different elements found in the p_________ table are the building blocks of all
materials. There are over 30 million materials made from just over 100 elements. In iron, all the
atoms are the same, because iron is an element. In a material like steel, all the atoms are not the
same. Steel contains iron atoms, carbon atoms and other metals atoms like chromium and
nickel. Iron, the pure element is like any other metal, but it rusts, combining readily with
o________ and water. Steel which does not rust is also much stronger. That’s why we use the
majority of iron for making steel. What is a metal alloy and give two examples ?
Materials and what they contain: Word bank: periodic oxygen
Iron Steel Glass Tungsten
Diagram
Iron extracted from Steel is stronger and Glass a transparent non Tungsten extracted from
Notes
iron ore is a pure more rust resistant than absorbent material used tungsten oxide is a pure
element containing iron because it also in windows and glasses element containing only
only one type of atom: contains the elements: contains the elements: one type of atom:
Iron. Iron, Carbon, Nickel & Calcium oxygen & Tungsten
Chromium. silicon.

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Understanding materials three
The combination and ratio of e_________ that are found in materials like glass, fibres,
ceramics or plastics determines all their physical properties. These properties include its
colour, whether it is hard, dense or soft, whether it has a high or low melting point or even
whether the material is a good or poor conductor of h_____ and electricity. These
properties make the material useful for a particular function. There are over 50 metals
naturally occurring, list their properties and explain why they’re very useful elements ?
Materials and what they contain: Word bank: elements heat
Gold Plants Atmosphere Computer chips
Diagram
Gold found and Plants contain many Earth's atmosphere which Computer chips made by
Notes
extracted from river thousands molecules insulates us, allows companies like Intel form
beds is a pure element which contain the respiration and protects the central part of the
containing only one following elements: us from UV rays contains computer contain only
type of atom: the following elements: one type of atom:
Hydrogen, Iron Oxygen
Oxygen, Nitrogen &
Gold Carbon, Nitrogen & Silicon
Noble gases.
Phosphorus

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The periodic table one
Elements in the periodic table are arranged by their atomic number which is determined by the
number of p________ each element contains. Using this rule, gives rise to groups of elements
with similar chemical and physical properties. There are eight distinct groups of elements, for
example group one elements are the reactive alkaline metals. There are also 30 elements known
as the transitional metals. There are five periods or rows. Each element has its own unique
s__________ which is used all over the World to save time. Find the symbols for the following
elements: Sodium, Gold, Iron, Oxygen, Nitrogen and Neon ?
The periodic table: Word bank: protons symbol
The periodic table (Look at the metallic, non metallic and semi metallic elements) Describing elements
Each element has its own
The Alkaline Metals
H He
The Alkaline Earth Metals symbol, atomic number and
1 2
Metals
atomic mass. The symbol for
Semi Metallic Elements
I II III IV V VI VII VIII
each element is unique. This
Non-Metals
Li Be B C N O F Ne
The Halogens
is not always the first letter
3 4 5 6 7 8 9 10
The Noble Gases
Na Mg Al Si P S Cl of the element.
Ar
12
11 13 14 15 16 17 18
K Ca Kr
Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br
19 20 36 12
21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 Atomic mass
Rb Sr Xe
Mo
Y Zr Nb Tc Ru Rh Pd Ag Cd In S Sb Te I
C Symbol
37 38 42 54
39 40 41 43 44 45 46 47 48 49 50 51 52 53
Cs Ba Hg
La Hf Ta W Re Os Ir Pt Au Ti Pb Bi Po At Rn Atomic number
6
55 56 80
57 72 73 74 75 76 77 78 79 81 82 83 84 85 86
Fr Ra
87 88
There are over 100 elements in the periodic table. There are eight groups, the transitional metals and five periods or
rows in the periodic table. Each vertical group of elements have very similar chemical and physical properties because
of their similar electronic configuration (electrons in shells)

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The periodic table two
Each element in the periodic table has its own very different properties. Metals and
non-metals have very different uses and p__________. Metals like copper, aluminium,
zinc and iron are hard, shiny, dense, malleable, ductile, conductive of heat and
electricity. Non-metals like carbon and sulphur usually have the opposite properties.
They are d______, soft, brittle and poor conductors of heat and electricity. Are there
any exceptions to these general properties for metals ?
Metals in the periodic table: Word bank: properties dull
Iron Aluminium Lithium Gold
Iron is used to build Aluminium with its Lithium is an extremely Gold has a high
complex machines and high strength to weight soft and reactive metal. monetary value and is
super structures like ratio is used in planes Although it cannot be used to make jewellery.
the French Eiffel and bike frames. It is used like iron or copper it Governments use gold to
tower. Corrosion can also a safe material to is used in batteries like guarantee their paper
be a problem. store fizzy drinks. the one pictured here. currencies.

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The periodic table three
Most of the elements in the periodic table are metals, but what about the non metals. Some are
solids like carbon and sulphur, some are liquid like b________, but most are gases like
nitrogen, oxygen and chlorine. Carbon is found in all fuels and biological molecules. Many of
the gaseous elements are found in our atmosphere, for example o_______ which is essential for
respiration and combustion of compounds containing carbon. The halogens including chlorine
and iodine all have antiseptic properties. The Noble gases which includes helium are a family
of un-reactive gases. Are there any exceptions to these general properties for non metals ?
Non metals in the periodic table: Word bank: bromine oxygen
Element Carbon (Diamond) Carbon (Graphite) Hydrogen Neon
Diagram
Notes
Notes Carbon atoms Carbon atoms Hydrogen molecules Neon atoms

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Elements one
Each element has an internationally recognised symbol and unique atomic and mass number.
Atoms of different elements like sodium (reactive group I metal) and chlorine (reactive group
VII non metal gas) are all made from three identical sub atomic particles. Elements are made
from e_________, protons and neutrons. The only difference between elements is the number
of each sub atomic particle. Therefore, the number of electrons, protons and neutrons each
element contains determines all their physical and chemical properties. What makes a reactive
metal like s_______, simply 11 electrons and protons and 12 neutrons. What makes a reactive
gas like chlorine, simply 17 electrons and protons and 20 neutrons and that’s it !!
Elements: Word bank: electrons sodium
Mercury Gold Oxygen Sulphur
Diagram
Particle
diagram
Notes Mercury atoms Gold atoms Oxygen molecules Sulphur atoms

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Elements two
Elements in the periodic table exist in eight vertical g________. There are also 30 metals which
are known as the transitional metals. Elements in the same group have the same number of
electrons in their outermost shell. They also have very similar physical and chemical properties.
The halogens located in group VII are all reactive non metals, with general antiseptic
properties: Fluoride in toothpaste, Chloride in s____________ pools and Iodide for skin prior
to surgery. Find out about the group I metals (alkaline metals) or the group VIII Nobles gases.
Do they have similar chemical and physical properties ?
Elements: Word bank: groups swimming
The halogens Fluorine Chlorine Bromine Iodine
F
9
9P+ 35P+
9N 35N
Cl 9E- 35E-
17
Fluorine Bromine
Br 17P+
35 53P+
17N 53N The halogens all have seven electrons in their outermost shell.
They exist as diatomic molecules and can form new compounds
-
17E
I 53E-
with other non-metals or metals. They are used for their
53 Chlorine Iodine
antiseptic qualities.

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Molecules one
In some elements like nitrogen and oxygen, the atoms pair up. A particle that consists of
more than one atom is called a m_________. All the group VII halogens: Fluorine,
Chlorine, Bromine and Iodine also pair up in molecules. We can show how many atoms a
molecule contains by using a chemical formula. Oxygen for example, consists of two
oxygen a______ with the formula O2. Nitrogen contains two nitrogen atoms with a
formula of N2. Write down the formula of fluorine, chlorine, bromine & iodine ?
Molecules of elements: Word bank: molecules atoms
Oxygen Nitrogen Hydrogen Ozone
Diagram
N N
N2 H2 O3
O2
Oxygen found in our Nitrogen is found in our Hydrogen is not found Ozone is made from three
Notes
atmosphere is used atmosphere and makes on its own. It is bound atoms of oxygen and is
during respiration by up nearly 79% of it. It is to other elements in found in the top layers of
all cells. Oxygen is inert in this form but in compounds like water. our atmosphere. Without
produced by green nitrates it is absorbed and Hydrogen is also the ozone, UV light would
plants during photo- used by plants to build fuel of our own Sun in prevent all life from
synthesis. proteins. the solar system. surviving.

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Molecules two
Molecules containing more than one type of atom are the building blocks of all
compounds. In a compound, the atoms of different elements are chemically
b________ together. Water for example, is a compound made up from two elements;
hydrogen and oxygen. We can represent how many atoms of each element and how
they are joined to each other using a chemical formula or a particle diagram.
Ammonia the compound, has a formula NH3. This tells us that a single ammonia
molecule contains three atoms of h_________ joined to one atom of nitrogen.
Molecules of compounds: Word bank: bonded hydrogen
Hydrochloric acid Water Ammonia Methane Sulphur dioxide
Diagram
H20 NH3 CH4 S02
HCl
HCl is used in Water is called Ammonia is made Methane, a fossil Sulphur dioxide is
Notes
laboratories and is and known as the during the Haber fuel is removed emitted as a
also found in the molecule of life. industrial process from underneath pollutant during
stomach. The HCl It is essential for and is an important the rock. Methane the combustion of
Acid helps protein all life to exist starting compound is combusted with fossil fuels like
digestion. here on Earth. for fertilisers. oxygen. petrol.

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Compounds one
There are over 30 million different materials or compounds. These are made from just over 100
elements. These elements must join up in different ways. We can show what a compound is
made from by knowing its f__________. The formula tells us the type of atoms and how many
of them we find in the simplest unit of a compound, a molecule. Compounds can be very
simple like sodium chloride and water or very complex like most biological molecules. These
molecules, found in cells like p_________ or even DNA are very complex and can have as
many as 100,000 atoms in a single molecule.
Simple and complex compounds: Word bank: formula proteins
Sodium chloride Methanol DNA Protein
Diagram
le le lex lex
Notes i mp i mp mp mp
S S o o
C C
Carbon, Oxygen, Carbon, Oxygen,
Contains Sodium & chlorine Carbon, Oxygen &
Phosphorus, Hydrogen, Hydrogen & Nitrogen
Hydrogen
Sulphur & Nitrogen

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Compounds two
A compound contains two or more types of a_______ joined together by a chemical bond.
The particles in a compound are known as molecules. Compounds always have a formula
which always tells us which and how many e__________ they are made from. There are
millions of compounds all made from elements found in the periodic table.
In the table we will examine the following compounds: Sand, Water, Methane and
Glucose.
Simple compounds and their formulae: Word bank: atoms elements
Sand Water Methane Glucose
Picture
Diagram
Formula SiO2 H2O CH4 C6H12O6

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Compounds three
Knowing and understanding compounds and their many formulae, allows us to understand
what happens to elements and molecules during a c_________ reaction. During photosynthesis
for example, water and carbon dioxide are combined in the leaf to make glucose and oxygen.
Glucose contains the elements carbon, hydrogen and oxygen found in the starting substrates,
carbon dioxide and water. A single molecule of glucose contains 6 atoms of carbon, 12 atoms
of hydrogen and 6 atoms of o_________. Its formula is therefore C6H12O6. We can see a single
molecule of glucose, but many millions or even billions make up a single glucose crystal.
Photosynthesis in green plants: Word bank: chemical oxygen
Inside the leaf Notes
Diagram All producers are able to combine CO2 and H2O
during photosynthesis producing glucose.
C6H12O6
6H2O
Cellular photosynthesis equation:
Chloroplast
Light energy
6CO2 6O2 6CO2 + 6H2O C6H12O6 + 6O2
Plant leaf Carbon dioxide Water Glucose Oxygen
During photosynthesis in green leaves, a single molecule of glucose and six molecules of oxygen are
made from combining six molecules of carbon dioxide and six molecules of water. Light energy is used
to break the bonds between the atoms of carbon dioxide and water. When glucose molecules are formed,
they are then taken to the rest of the plant and then used in cellular respiration or combined with more
glucose molecules to form starch, a polymer of glucose.

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Relative atomic mass one
Each e_________ in the periodic table has a unique atomic number and relative atomic
mass. We can use the atomic number and mass number to build a complete picture of an
atom. The atomic number of an atom tells us the number of protons found in element’s
nucleus. Subtracting the atomic number from the m______ number gives the number of
neutrons. In an uncharged element the number of protons equals the number of electrons.
Work through the four examples below, giving the number of neutrons, protons and
electrons ?
Atomic mass: Word bank: element mass
Element Lithium Carbon Oxygen Calcium
Diagram 40
12 16
7
C O
Li Ca
6 8
3 20
3P+ 6P+ 8P+ 20P+
4N 6N 8N 20N
3E- 6E- 8E- 20E-
Lithium Carbon Oxygen Calcium
Mass
Seven Twelve ____________ ? ____________ ?
Number
Atomic
Three Six _____________ ? ____________ ?
Number

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Relative atomic mass two
Single atoms have a very s_______, almost negligible mass. The mass is so small that it makes
it impossible to use in calculations. Instead, an element’s mass is compared with other
elements. Relative atomic masses has been calculated for all elements, so that we can compare
the mass of one element relative to another. For example: hydrogen has a mass of one on this
scale, h________ is four times heavier, at four. Carbon is twelve times heavier, at twelve. Link
the relative atomic mass of an element with the number of protons and neutrons that each
element contains. Why do electrons appear not to contribute to the mass of an element ?
Comparing masses of elements: Word bank: small helium
Element Hydrogen Helium Carbon Magnesium
Diagram 24
4 12
1
C
H 2 He
Mg
6
1 12
1P+ 2P+ 12P+
6P+
1E- 12N
2N 6N
2E-
6E- 12E-
Hydrogen Helium Carbon Magnesium
Mass One Four Twelve Twenty four
Number
Hydrogen
r
fou
Equivalents
y
e
ent
elv
on e r
fou tw tw

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Elements and electron shells one
The atomic number of an element also tells us the number of electrons that an element has.
These electrons are arranged in s_______ or orbits around the positive nucleus. These
shells are also sometimes called e_______ levels. Electrons start filling the inner shell
first. The inner shell contains two electrons. The next two shells each contain eight
electrons. The fourth shell can contain up to eighteen electrons. Look at the first six
elements: Hydrogen, Helium, Lithium, Beryllium, Boron and Carbon. How do the number
of electrons found in the element’s outer shell relate to their position in the period table ?
Elements and electron shells one Word bank: shells energy
Elements one to six Hydrogen Helium Lithium
4 7
1
He Li
H 2 3
1
1P+ 3P+
2P+
2N
1E- 4N
2E-
3E-
Beryllium Boron Carbon
11 12
9
B C
Be 5 6
4
4P+ 5P+ 6P+
5N 6N 6N
4E- 5E- 6E-

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Elements and electron shells two
As the atomic number of an element increases, so do the number of electrons. When each
electron shell is f_______ a new one begins to fill with electrons. It is the electron
arrangement of an element that determines its c__________ properties. During chemical
reactions, elements either gain, lose or share their electrons. Find out the difference in
what happens to electrons during the formation of an ionic and covalent product ?
Elements and electron shells two Word bank: filled chemical
Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminium
14 19 20
16 23 24 27
N O F Ne Na Mg Al
7 8 9 10 11 12 13
Silicon Phosphorus Sulphur Chlorine Argon Potassium Calcium
28 40 39
35 40
31 32
Si P S Cl Ar K Ca
14 15 16 17 18 19 20

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Compounds and relative formula mass one
Once you understand the relative atomic mass of a______, you can also work out the
relative mass of any molecule or compound. Using its formula, all you have to do is
add up the masses of each type of atom present in the molecule. For example if the
relative atomic mass of oxygen is 16 g then the relative formula mass for a molecule
of oxygen is twice 16 g, therefore 32 g (O2: 2 x 16 = 32 g) Work out the relative formula
mass for the following compounds SO2, CO2, C2H6 & CO ?
R.A.Ms: H = 1, C = 12, N= 14, O = 16, Ca = 20, Al = 27, S = 32.
Relative formula mass one Word bank: atoms
Compound Methane Oxygen Water Nitrogen
Diagram
Oxygen Water
Methane Nitrogen
Formula CH4 O2 H2O N2
Relative 1 C = 1 x 12 2 O = 2 x 16 1 O = 1 x 16 2 N = 2 x 14
+ +
formula
4H= 4x 1 2H=2x 1
mass (Mr )
Total = 16 g Total = 32 g Total = 18 g Total = 28 g

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Compounds and relative formula mass two
Working with relative atomic and formula masses allows us, as scientists to solve
problems involving qualities of raw m__________ and end products. Example: How much
water in grams would be formed if I reacted 1000 g of hydrogen in excess oxygen. The
equation tells us that 4 g of hydrogen reacts with 32 g of o_________ to produce 36 g of
water. Therefore 1000 g of hydrogen would yield in excess oxygen 9000 g of water (250 x
36 = 9000) Work out the following relative formulae masses in the table below ?
R.A.Ms: H = 1, C = 12, N= 14, O = 16, Ca = 20, Al = 27, S = 32.
Relative formula mass two Word bank: materials oxygen
Compound Ethene Ammonia Hydrogen peroxide Methanol
Diagram
Formula C2H2 NH3 H2O2 CH4O
Relative 2 C = 2 x 12 __________ ? __________ ? __________ ?
formula
2H= 2x 1 __________ ? __________ ? __________ ?
mass (Mr )
Total = 24 g Total = ___? Total = ___? Total = ___?

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Equations and conservation of mass one
When substances react, new products formed are shown by an equation. An equation
tells you the substrates and their formulae and the resulting products and their
formulae. During the r_________, bonds are broken and new ones are formed,
however the number of atoms on both sides of the e__________ remain the same.
Conservation of mass tell us that you can’t destroy or create atoms during a chemical
reaction ! (R.A.Ms: H = 1, C = 12, O = 16)
Combustion of methane with oxygen: Word bank: reaction equation
Equation CH4 + 2O2 CO2 + 2H20
Methane Oxygen Carbon dioxide Water
Diagram
Formula CH4 2O2 CO2 2H2O
Relative 1 C = 1 x 12 4 O = 4 x 16 1 C = 1 x 12 4H= 4x 1
formula
4H= 4x 1 2 O = 2 x 16 2 O = 2 x 16
mass (Mr)
Total = 16 g Total = 64 g Total = 44 g Total = 36 g
Total (RHS) _____ ? Total (LHS) _______ ?

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Equations and conservation of mass two
Conservation of mass tell us that you can’t destroy or create atoms during a chemical
reaction ! This is true for all chemical reactions. An example is the formation of
water. During this reaction, h_________ molecules (H2) react with oxygen molecules
(O2) to form water molecules (H20) At the beginning of the reaction, both the
hydrogen and oxygen molecules are broken apart to form their a_______. These
atoms then join one another, to form water molecules (H2O) Again the total number of
atoms on either side remains the same ! (R.A.Ms: H = 1 & O = 16)
Formation of water: Word bank: hydrogen atoms
Equation Hydrogen + Oxygen Water
Diagram
O
H H H H
O O
O
H H
H H
Formula 2H2 O2 2H2O
4H= 4x 1 2 O = 2 x 16 4H= 4x 1
Relative
formula 2 O = 2 x 16
mass (Mr) Total = 4g Total = 32 g Total = 36 g
Total (RHS) _______ ? Total (LHS) _______ ?

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The mole one
You know about relative atomic mass, but how was it worked out. For example, why is the
RAM of carbon 12 and the RAM of oxygen 16 ? Well its all down to the mole. A mole in
chemistry is a specific number of atoms, to be precise 6 x 1023 atoms. It allows chemists to
talk about the same number of p__________ for all the elements. For example 6.0 x 1023
atoms of carbon weigh 12 g and 6.0 x 1023 atoms of oxygen weighs exactly 16 g. The mole
is the standard unit for particles. You can have a m______ of atoms, molecules, ions or
even electrons, with whatever you have, its always 6 x 1023 of them.
The mole: Word bank: particles mole
Compound Hydrogen Carbon Oxygen (Atomic) Oxygen (Molecule)
Diagram 1 12 16 16 16
H C O O O
6 8 8 8
1
1P+ 6P+ 8P+ 8P+ 8P+
1E- 6N 8N 8N 8N
6E- 8E- 8E- 8E-
Hydrogen Carbon Oxygen O2
6.0 x 1023 atoms 6.0 x 1023 atoms 6.0 x 1023 atoms 6.0 x 1023 molecules
Particles
s
ule
le c
ms
s s
to m to m mo
ato
a a 3
23
23 23 2
10
10
10 10 x
x
x x
6.0
6.0
6.0 6.0

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The mole two
Working with relative atomic masses and the mole allows us to understand equations and know
exactly how much substrates and p__________ are involved during a chemical reaction. Example:
Haematite or iron ore is used to produce iron. In the blast furnace, iron ore is reduced by carbon
monoxide to yield iron and carbon dioxide. How much iron will be produced from 100 kg of iron ore
providing there is sufficient quantities of carbon monoxide ? Follow the solution (R.A.Ms: C = 12
O = 16, Ca = 20, Fe = 56)
Extracting iron: Word bank: products
Iron extraction Smelting process Calculation:
Formation of carbon monoxide The equation tells us that 3 moles of carbon
monoxide are required to reduce 1 mole of
2C + O2 2CO (1700oC)
iron oxide producing 2 moles of iron metal
Notes: The carbon in coke reacts with
and 3 moles of carbon dioxide.
oxygen to form carbon monoxide a
powerful reducing agent.
So how much iron in mass and moles will
Reduction of iron oxide you obtain from 100 kg of iron ore ?
3CO + Fe2O3 2Fe + 3CO2 (900oC)
Solution: Mr of Fe2O3 is 160 g (2 x 56 + 3 x
Notes: The carbon monoxide gas displaces
16) Every 160 g of iron oxide produces 112 g
iron from its oxide producing carbon
dioxide and molten iron which is then
(2 x 56) of iron which gives a 70% yield
collected.
(112/160). 100 kg of Fe2O3 will therefore
Impurity Formation (Slag) produce 70% or 70 kg of iron metal. 70 kg or
70,000 g of iron is equivalent to 1250 moles
CaCO3 + SiO2 CASiO3 (1200oC)
of iron (70,000/56). What would be the yield
Notes: Limestone reacts with silicon
for 2500 kg of iron oxide be ?
impurities to form slag which floats to the
surface and is then removed.

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Extension questions and homework
1: Define the following terms: Atom, Molecule, Compound, Element, Material & Particle
2: Complete the table.
A B C D E
Pure element of only _______________ _________________ _______________ ________________
one type of atom ______________? ________________? ______________? _______________?
3: a) Give three examples of each of the following; Elements, Single molecules and compounds
b) Based on their physical properties answer the following.: Why is gold metal use for rings and necklaces. Why is
iron used to build bridges and other structures like buildings.
c) The chemical formula of carbon dioxide is CO2, of sugar C6H12O6 what does this tell you about both molecules
and the elements present.
d) Work out the relative atomic mass (Ar) or relative formula mass (Mr) of the following: CaCO3, Al2O3, NaOH,
H2, C4H10 & C12H24, CuSO4, CO, H20, Fe2O3, O3, O2, H2O2 + SO2 (RAM H = 1, C = 12, O = 16, Na = 23, Al = 27,
S = 32 & Ca = 40)
4: Complete the table.
Element Symbol Ar & RAM Protons Neutrons Electrons
23 Na
Sodium Na 11 12 11
11
Aluminium Al 27 Al
13
Uranium U 92 143 92

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5: Which one of the following reactions are correctly balanced?
a) Fe3O4 + 2H2 3Fe + 2H2O
b) H20 H2 + O2
c) H2O2 H2O + O2
d) Mg(OH)2 MgO + H2O
e) 2Na + H20 2NaOH + H2
6: Balance these following equations:
a) H2 + O2 H2O
b) Al + O2 Al2O3
7: Choose from this word list to complete the sentences below:
Hundreds Millions Tens Thirty Ninety Twenty
There are about _________ naturally occurring elements. From these elements ___________ of different substances
can be made.
8: A pure substance was melted then allowed to cool. The temperature of the substance was measured every minute as
it cooled down. The results are given.
a) Plot a graph of temperature against time.
b) What is the melting point of the substance.
Time (min) 0 1 2 3 4 5 6 7 8
Temperature (oC) 74 58 55 54 54 54 53 49 45
Internet:
Go to google.co.uk and find out about the three forms of the element carbon; Diamond, Graphite and Buckminster
fullerene. Cut and paste diagrams and write an a sentence about each type.