1. REVIEW OF THE ATOM

2. Sub-atomic Particle Where FoundCharge ProtonNucleus+1 NeutronNucleus0 ElectronAround nucleus

3. Helium Atom - He 2 electrons 2 protons 2 neutrons nucleus He 2 4.00 Helium

5. Definitions (refer to handout) Atom – small particles that make up everything around us (matter). Element – If a substance is made up of only one type of atom. Eg. Zinc, Oxygen, Copper. Compound – a substance that contains two or more different elements that are chemically combined. Eg. Copper Sulphate, Water. Mixture – a substance that contains two or more different substances that are not chemically combined. Proton – a positive charged particle held within the nucleus of an atom. Neutron – an uncharged particle held within the nucleus of an atom. Electron – a negatively charged particle that is free to move around the nucleus.

6. The Parts of the Atom Electron Orbit Neutron Proton Nucleus

7. Atomic Number – the number of protons in an atom. Mass Number – the number of protons and neutrons in an atom. Atomic Mass – the average Mass Number of all the different isotopes of an element. Isotope – when two atoms have the same number of protons but a different number of neutrons (therefore a different mass number). Ion – an element or a compound, which takes on a charge due a variation between the number of protons and electrons, it possesses. (cation +, anion -) Ionic Charge – the charge of an atom. Eg. Oxygen contains 8 protons and 10 electrons, therefore 8 positive charges and 10 negative charges, i.e. 2- charge. Definitions (refer to handout)

8. Parts of the Periodic Table Hydrogen 1 1.007 Name of the ELEMENT. Atomic number of the element Symbol for the element. Atomic Mass of the element H

9. Review of the Periodic Table Lithium 3 6.941 What is the symbol for Lithium? _________ What is the atomic number of Lithium? _________ How many protons does Lithium have? _________ How many electrons does a neutral Lithium atom have? __________ What is the atomic weight for Lithium? _______________ Li 3 3 6.941 3

10. Physical properties are properties which do not involve the substance turning into something else Eg. appearance, texture, colour, odour, melting point, boiling point solubility,

11. Chemical properties are properties that substances show when they undergo changes to something else Eg. Flammability Reactivity

12. Questions 1. What chemical property is shared by petrol, wood, kerosene and coal? 2. What are the physical properties of cement 3. Classify the following as physical / chemical properties Soluble Smooth Rusty Produces bubbles when acid added Round FLAMABLE HARD, not soluble (insoluble) in water, GREY, solid at room temp. Physical Chemical Physical

13. Physical Changes During a physical change the substance remains the same substance, but some of its properties may change A physical change can be reversed Examples include, changes to; Size Shape State (solid, liquid, gas) Ie: melting chocolate, freezing water…

15. Chemical Changes In a chemical change, one or more new substances are formed Chemical changes are the result of chemical reactions Examples include; Production of gas Production of heat or light A permanent change in colour The formation of a precipitate (new solid) Ie: rusting iron

17. REVIEW In this type of change the substance remains the same substance. _________________ In this type of change the substance turns into a different substance _________________ Physical Change Chemical Change

18. IONS Ions - are atoms or groups of atoms that have a positive or negative charge. Ions are formed when an atom gains or loses an electron. The charge on an atom can only change by changing the number of electrons. You can’t change protons

19. Ions - += Zero (0) overall charge + + + + - += - _______ overall charge + + + + - += - - + + + + - - - - -

20. IONS Metals tend to lose electrons becoming positive (+) Non-Metals tend to gain electrons becoming negative (-)

21. Ions Cations - are ions, which have a positive charge (due to losing electrons) Anions - are ions, which have a negative charge (due to gaining electrons) Polyatomic ions - are groups of atoms that have a charge and act as a unit. Eg. SO 4 2- contains 1 Sulphur and 4 Oxygen atoms and carries a 2- charge. Diatomic elements - are two atoms of the same element bonded together. Eg. H 2, I 2, Br 2, Cl 2, O 2, N 2, Hg 2,

22. Cation or Anion?