atomic science year 10
TRANSCRIPT
Atomic Science
Year 10Ms Gibellini
SLOs
Video
Introduction
Recognise various HAZCHEM symbols
SLO
Distinguish between chemical and physical changes
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How many physical and chemical changes can you spot?
What is a chemical reaction?
cooking rusting sticking
burning making metals living!
Can you think of any other chemical reactions?
Chemical reactions do not only happen in the laboratory.
Chemical reactions happen anywhere that new substances are made:
Reactants and Products
The starting substances used in a reaction are reactants.
The new substances formed in a reaction are products.
In a chemical reaction, one or more new substances are formed.
The arrow means “change into”. In a chemical reaction, all the reactants change into the products.
It is difficult to reverse a chemical reaction and change the products back into the reactants.
More about Chemical Changes
Chemical changes are usually difficult to reverse.
Magnesium burns in oxygen to form magnesium oxide. It is not possible to “un-burn” the magnesium once it has been burnt.
Many reactions need energy to get them started. Many reactions (like the burning of magnesium) give out heat energy once the reaction has started.
Heat energy being given out is one sign of a chemical reaction. What other signs of a chemical reaction are there?
magnesium oxideoxygenmagnesium
Reactions all around usHow many chemical reactions go on around us everyday?
Chemical Reactions
Reactant 1 + Reactant 2 Observations
Hydrochloric Acid
Vinegar
Ice Heat
Potassium Iodide
Lead Nitrate
Sugar Water
Magnesium Oxygen + heat
Iron Copper sulphate
Chemical ReactionsReactant 1 + Reactant 2 Observation
sHydrochloric Acid
Vinegar No reaction
Ice Heat Melts and turns to liquid water
Potassium Iodide
Lead Nitrate Yellow
Sugar Water Dissolved.
Magnesium Oxygen + heat White light, white powder
Iron Copper sulphate
Red on wire, blue colour goes clear
Chemical Reactions
When a chemical reaction or chemical change occurs when:
Heat is given off Colour change Gas is given off (bubbles, fizzing) Something new is made A precipitate is made
Elephant Toothpaste
H2O2 + food colouring + detergent + solid potassium iodide. http://www.youtube.com/watch?v=7qtX6XgDeDY
Physical Change Reactions
When a physical change occurs chemicals change from one state to another, and nothing new is made.
Eg Ice cream meltingWater freezing
Making Ice cream
Put the following into a ziploc bag and seal it 2 tablespoon sugar 1 cup milk 1/2 teaspoon vanilla
Put the following into the ice cream container, put the lid on and shake it. 6 tablespoons rock salt Ice cubes Bag with milk, sugar and vanilla in
Complete Scipad pages 8-9 Chemical Change vs Physical Change
List three ways you know a chemical change has occurred
List two chemical changes and state why they are a chemical change
List two physical changes and state why they are a physical change
Success Criteria
Define the term ‘element’
Begin to understand the structure of the periodic table
SLO
There are millions of different substances!What are they all made of?
How many different substances
can you think of?
All substances are made of Atoms
All substances are made of very tiny particles called atoms.
hydrogen and oxygen atoms
carbon and hydrogen atoms
carbon, nitrogen, hydrogen, oxygen and sulphur atoms
iron, aluminium, silicon, oxygen
and boron atoms
Many substances are made up of different types of atoms.
What is an element?
All substances are made of very tiny particles called atoms.
The elements are the simplest substances in the universe.
The elements are the building blocks of all other substances.
copper
carbon
There are about one hundred substances that are made up of just one type of atom. These are the elements.
helium
Element
Symbol
Description
State
Use
Elements
An element is a substance made up of only one type of atom.
Atoms in elements
Copper is an element made up of copper atoms only.
Carbon is an element made up ofcarbon atoms only.
Helium is an element made up ofhelium atoms only.
Atoms and molecules of elements
In some elements, the atoms are joined in groups of two or more. A particle containing atoms grouped in this way is called a molecule.
An element is a substance made up of only one type of atom.
Other elements, that contain atoms joined in molecules are hydrogen, nitrogen, chlorine and bromine.
Oxygen is an element made up of oxygen atoms only.
How many atoms are there in an
oxygen molecule?
1) Hydrogen
2) Helium
3) Lithium
4) Beryllium
5) Boron
6) Carbon
7) Nitrogen
8) Oxygen
9) Fluorine
10)Neon
11)Magnesium
12)Aluminium
13)Silicon
14)Phosphorus
H
He
Li
Be
B
C
N
O
F
Ne
Mg
Al
Si
P
Elements to Learn
15)Sulphur
16)Chlorine
17)Argon
18) Calcium
19) Zinc
The less obvious ones:1) Sodium
2) Potassium
3) Iron
4) Copper
5) Silver
6) Tin
7) Gold
8) Mercury
9) Lead
S
Cl
Ar
Ca
Zn
Na
K
Fe
Cu
Ag
Sn
Au
Hg
Pb
How to write symbols for elements
Two important rules should be followed when writing the symbols of elements so that there is no confusion.
1. The first letter of an element’s symbol is always a capital letter.
2. If there are two letters in the element’s symbol, the second letter is always a small letter.
e.g. N (not n) for
nitrogen
e.g. Co (not CO) for cobalt
No, Watson! It was carbon monoxide
poisoning – not cobalt.
The Story of ‘The Kid’
Elements have been put in order of:
Physical properties Chemical properties Atomic number Mass number Number of electrons in outer shell
on the Periodic Table of Elements
Atoms and Elements
Periodic Table
Arranging Elements
antimony (Sb)
Is this element a or a ?
H
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
He
B C
AsFeFe
Mg SPMg SP
CuCu
metal non-metal
IISb
Hard to say!
Sb
Metal or Non-metal?
iodine (I)iron (Fe)copper (Cu)phosphorus (P)sulfur (S)magnesium (Mg)
Metals and non-metals in the periodic table
The periodic table is a list of all the known elements which are arranged according to the similarities in their properties.
Non-metals are mostly on the right.
Metals are on the left and in the centre.
What type of elements are between metals and non-metals?
Xe
H
Li
Na
K
Rb
Cs
Fr
Be
Sc Ti
Mg
V Cr Mn Fe Co Ni Cu Zn Ga Ge Se BrCa Kr
Y Zr Nb Mo Tc Ru Pd Ag Cd In Sn SbSr TeRh
Ba Hf Ta W Re Os Ir Au Hg Tl Pb Bi PoLa AtPt
Ra Rf Db Sg Bh Hs Mt ? ?Ac ?
Al P
N O
S Cl
F Ne
Ar
Rn
I
Si
Xe
He
B C
As
silicon (Si) metalloidfrancium (Fr) metalscandium (Sc) metalkrypton (Kr) non-metalcobalt (Co) metal
What aremetalloids?
Which side are the non-metals on?
Which side are the
metals on?
Metalloids sometimes behave like metals and
sometimes like non-metals.
Metals are on the left and in
the centre.
Non-metals are mostly
on the right.
15/04/2023
Mendeleev
Periodic tableThe periodic table arranges all the elements in groups according to their properties.
Horizontal rows are called PERIODS
Vertical columns are called GROUPS
15/04/2023
H He
Li Be B C N O F Ne
NaMg
Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
Ag I Xe
Pt Au Hg
The Periodic TableFact 4: (Most important) All of the elements in the same group have similar PROPERTIES. This is how I thought of the periodic table in the first place. 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
Understand the structure of the atom
Understand the key differences between the three sub-atomic particles
SLO
Discovery of Atomic Structure
How small is an Atom?Atoms are very small – they are about 0.00000001 cm wide.
N X3,000,000,000
If a football was enlarged by the same amount it would stretch from the UK to the USA!
To make an atom the size of a football it would have to be enlarged by about 3,000,000,000 times.
Atoms
All matter is made up of atoms Chemistry involves the rearrangement
of atoms or groups of atoms
The Amazing Atomic Zoom
Inside an AtomWhere are the electrons and nucleus found in an atom?
Atoms are mostly empty space . . .
Structure of atom
How do we know?
Even Smaller Particles
For some time, people thought that atoms were the smallest particles and could not be broken into anything smaller.
proton
neutron
electron
Scientists now know that atoms are actually made from even smaller subatomic particles. There are three types:
Where are subatomic particles found?
Protons, neutrons and electrons are NOT evenly distributed in an atom.
The electrons are spread out around the edge of the atom. They orbit the nucleus in layers called shells.
The protons and neutrons exist in a dense core at the centre of the atom. This is called the nucleus.
The AtomDraw a labelled diagram of the atom showing the nucleus and labelling protons, neutrons and electrons.
nucleus
neutron proton
electron
Atoms are made up of the following sub atomic particles:
Electrons negative charge outside nucleus, in shells constant motion very very small (1/2000 of a
proton)
Neutrons No charge, neutral Inside nucleus Same size as proton
Protons Positively charged Inside nucleus
Atoms have an overall neutral charge, therefore:
Number of protons = Number of electrons
Making Models . . .
You are going to make a model of the lithium atom, Li.
Li is Lithium, a metal.
Li has 3 protons, 3 _________ + 4 neutrons.
(remember atoms are neutral so they must have the same number of protons (positive) and electrons (negative)
Atom Model:
Protons – 1 colour of pebble
Electron – chocolate chip
Neutron – different coloured pebble
Nucleus - Marshmallow
Electron orbit - cotton
Success Criteria Copy the title into your
books, and draw your model atom.
Label your drawing, protons, neutrons, electrons
What colour pebble represents the protons?
What colour pebble represents the neutrons?
What particles make up the nucleus?
Complete Scipad page 10 Atoms
Atomic Number:
Smaller number Number of protons Number of electrons
Atomic Mass or Mass Number:
Bigger number of the two Total number of sub atomic particles Number of protons + neutrons.
Atom Information
How do we work out the number of:
Protons = Atomic number
Electrons = Atomic number
Neutrons = Mass number – atomic number
big number – small number
Atomic Information
How Many Protons?
The atoms of any particular element always contain the same number of protons. For example:
The number of protons in an atom is known as its atomic numberor proton number.
It is the smaller of the two numbers shown in most periodic tables.
hydrogen atoms always contain 1 proton;
carbon atoms always contain 6 protons;
magnesium atoms always contain 12 protons,
What’s the Atomic Number?
What are the atomic numbers of these elements?
11
sodium
26
iron
50
tin
9
fluorine
Atom Protons Neutrons Mass number
hydrogen
lithium
aluminium
Mass NumberElectrons have a mass of almost zero, which means that the mass of each atom results almost entirely from the number of protons and neutrons in the nucleus.The sum of the protons and neutrons in an atom’s nucleus is the mass number. It is the larger of the two numbers shown in most periodic tables.
1 0 1
3
13
4
14
7
27
127
What’s the Mass Number?
What is the mass number of these atoms?
73
59
64
4
Mass number = number of protons + number of neutrons
Atom Protons Neutrons Mass number
helium
copper
cobalt
iodine
germanium
2 2
29 35
27 32
53 74
32 41
How many Neutrons?
How many neutrons are there in these atoms?
Atom Mass number
Atomic number
Number of neutrons
helium 4 2
fluorine 19 9
strontium 88 38
zirconium 91 40
uranium 238 92
51
146
50
10
2
Number of neutrons = mass number - number of protons= mass number - atomic number
Properties of subatomic particles
15/04/2023
H He
Li Be B C N O F Ne
NaMg
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 (this corresponds to their group number)
E.g. all group 1 metals have __ electron in their outer shell
These elements have __ electrons in their outer shell
These elements have __ electrons in their outer shells
15/04/2023
H He
Li Be B C N O F Ne
NaMg
Al Si P S Cl Ar
K Ca Fe Ni Cu Zn Br Kr
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 3 electron in the configuration 2,1
Potassium has 19 electrons in the configuration __,__,__,__
Sodium has 11 electrons in the configuration 2,8,1
Complete Sci pad pages11-13 Elements, Getting the know the Periodic Table, Element Bingo
How can you tell if a chemical change has occurred?
Draw a labeled diagram of an atom, state the charge and size of each particle
What information does the atomic number tell us?
What information does the mass number tell us?
How many protons, neutrons and electrons does Lithium have?
Success Criteria
Draw the arrangement of electrons around any given atom.
SLO
Atom Protons Neutrons Electrons
helium
copper
iodine
How many Electrons?Atoms have no overall electrical charge and are neutral. This means atoms must have an equal number of protons and electrons.
The number of electrons is therefore the same as the atomic number.
Atomic number is defined as the number of protons rather than the number of electrons because atoms can lose or gain electrons but do not normally lose or gain protons.
2 2 2
29 35 29
53 74 53
Atom Protons Neutrons Electrons Atomicnumber
Massnumber
boron
potassium
chromium
mercury
argon
5
19
18
24
80
5
19
18
24
80
11
39
40
52
201
What are the missing numbers?
5 6
19 20
24 28
80 121
18 22
How are Electrons Arranged?
Electrons are not evenly spread but exist in layers called shells.
3rd shell
2nd shell
1st shell
The arrangement of electrons in these shells is often called the electron configuration.
How many Electrons per Shell?
Each shell has a maximum number of electrons that it can hold. Electrons will fill the shells nearest the nucleus first.
3rd shell holdsa maximum of8 electrons
2nd shell holdsa maximum of8 electrons
1st shell holdsa maximum of2 electrons
Electrons arrange themselves in regular order around the nucleus depending on their energy.
Each energy level holds a different number of electrons:
Level 1 – 2 electrons Level 2 – 8 electrons Level 3 – 8 electrons
Electrons fill from Level 1 shell, or the closet to the nucleus first.
Electron Shell Configuration
Thinly spread around the outsideof the atom.
Very small and light. Negatively charged. Found orbiting the nucleus in layers called shells. Able to be lost or gained in chemical reactions.
Summary: the Atom so far
The nucleus is:
Electrons are:
Dense – it contains nearly all the mass of the atom in a tiny space.
Made up of protons and neutrons. Positively charged because of the
protons.
Use the information on the periodic table to make dot diagrams of the following atoms:
He, H, Li, Be, B
Step 1: Write out the atomic informationMass number =Atomic number =Number of protons =Number of neutrons =Number of electrons =Electron shell pattern =
Step 2: Make a dot diagram
Step 3: Label the diagram
Task
Success Criteria Complete Sci pad page 14 A closer look at Electrons
List three chemical reactions and three physical reactions
What charge do protons, electrons and neutrons have?
An atom has 16 protons. How many electrons does it have?
A neutral atom has 4 electrons. How many protons does it
have?
Draw the electron configuration for Sodium, Atomic number 11
Understand the role of electrons in chemical reactions
SLO
Atoms require their outer shells to be full in order to be chemically stable
Atoms either lose or gain electrons to get a full outer shell (2,8,8 , 2 in first shell, 8 in second and third shells)
When atoms lose or gain electrons they become electrically charged and are then called ions
Gaining electrons results in a ________ ion Losing electrons results in a __________ ion
The number of protons stays the same
Ions
E.g
Na Na+ + e-
Sodium atom sodium ion Free electron2, 8, 1 2, 8,
Cl + e- Cl-
Chlorine atom electron Chlorine ion 2, 8, 7 2, 8, 8 The charge on an ion is called its valency. Valency always has a sign (+ or -) and a numerical value. (although we don’t write 1)
Complete page 15 of Sci pad The role of the electron
Calculating Charge
1. Work out how many electrons the atom has (mass number, group number)
2. Work out the electron shell configuration 2,8,8
3. Work out if electrons need to be gained or lost to make a full outer shell
4. If electrons are gained it makes the ion negative
5. If electrons are lost it makes the ion positive
Calculating Charge
What is the charge on a Sodium ion Electron Number = 11 Electron Shell = 2,8,1 Easiest to lose one electron Losing electrons means more
protons than electrons, so positive
Lost 1 so Na+
Success Criteria Complete page 15 of Scipad The Role of the Electron
How can you tell if a chemical change occurs?Gas given off, heat, colour change, cannot be reversed, precipitate Draw a labelled diagram of an atom
What does atomic number tell us? What does Mass number tell us?Atomic no.= number of protons, number of electronsMass No. = total number of particles in nucleus, no. protons + neutrons What is an ion, how does it form?When an atom gains or loses electrons, ion is an atom which has gained or lost electrons Draw an electron dot diagram for Carbon 12 and sulphur 16 Carbon – 2,8,2 Sulphur – 2,8,6 An ion has 8 protons and 10 electrons. What charge does it have? Negative charge, 2- Does an atom with 8 electrons in its outer shell form an ion (circle the correct
answer)? Yes/No No its already full, no reaction , its stable
Define the terms ‘compound’ and ‘mixture’ and give
examples of each
Determine the number of atoms in a compound given its
chemical formula
SLO
Elements are made of one kind of atom
Compounds are made of two or more elements chemically combined
Mixtures are made up of two or more elements which are NOT chemically combined
Elements Mixtures and Compounds
A compound has very different properties to the elements from which it is made.
carbon dioxide
A colourless gas which is used to put out fires.
to make
carbon
A black solid which can be
used as a fuel.
combines with
compound
elementsoxygen
A colourless gas which is essential
for life.
What are the elements which make up water? In what ways are the elements different to their compound?
to makecombines with
compound
elementswater
A liquid which is essential to our
lives and has many different uses.
hydrogen
A colourless gas which is used in hot air balloons.
A colourless gas which is essential
for life.
oxygen
Element or compound?
Aim: Investigate compounds and mixtures
Method: 1. Separate a mixture of iron and sulphur using a
magnet2. Heat a mixture of iron and sulphur to form iron
sulfide which is a compound3. Now try to separate iron with a magnet
Results:Mixtures can/cannot be physically separatedCompounds can/cannot be physically separated
Compounds and Mixtures
Elements contain only one capital letter Al, H, He
Compounds contain more than one element and therefore more than one capital letter H2O, CuSO4
Each capital letter represents a different atom
H2O has Hydrogen and Oxygen atoms in it How many different atoms does CuSO4
have in it?
Atoms and Compounds
The numbers in a compound tell us how many atoms there are:
H2O = two hydrogen atoms for every one oxygen atom
CO2 = two oxygen atoms for every one carbon atom
Methane has four hydrogen atoms for every one carbon atom, what is its formula? (Carbon goes first)
Complete Scipad page 18-19 Mixtures and Compounds
What is the difference between an element, mixture and a compound?
Identify the element, mixture and compound:
Complete Sci pad page 18-19
Success Criteria
Write word equations for chemical reactions
SLO
Reactant + Reactant products
Magnesium + hydrochloric acid magnesium
oxide
Complete Sci pad pages 16-17
Chemical Equations
Multiple-choice quiz
Name Symbol
Name Symbol
Name Symbol
Hydrogen
Potassium Zinc
Helium Magnesium Copper
Lithium Aluminium Lead
Beryllium
Silicon Silver
Born Phosphorus Gold
Carbon Sulphur Mercury
Nitrogen Chlorine Water
Oxygen Argon Carbon Dioxide
Fluorine Sodium Sulphuric Acid
Neon calcium Hydrochloric acid
Elements Test