atomic science year 10

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Atomic Science

Year 10Ms Gibellini

SLOs

Video

Introduction

Recognise various HAZCHEM symbols

SLO

Distinguish between chemical and physical changes

SLO

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

Element Song

Daniel Radcliff

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

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