1. Review Periodic Table Bill Nye The Science Guy Elements & electrons
Today:
Review Periodic Table Bill Nye The Science Guy Elements & electrons

2. This week: elements & electrons
Reaction lab – Due Tuesday
Marks: 10 observations/questions
25 for your conclusion
TEST– Thursday Graphing
States of Matter
Atomic history
Periodic Table

3. I will be looking at your lab’s conclusion
Conclusions must be based on your RESULTS A black colour, thick smoke and a strong odor were observed when bread was toasted for 30 minutes. As the colour remained when cooled, a new substance was created and a chemical reaction observed.

4. Elements
Matter is anything that takes up space and has mass. Elements and compounds are pure substances: An element is ONE TYPE of atom and cannot be broken down or separated into simpler substances.

5. Periodic Table Origin of the periodic table
In 1867, Dimitri Mendeleev found patterns in the elements and organized them into table
The resulting table had holes
for elements not yet discovered

6. Periodic Table
The Periodic Table provides information on the physical and chemical properties of elements and ______ ________.
Atomic Mass - mass of average atom
Atomic Number - number of protons
Ion Charge - electric charge that forms when an atom gains or loses electrons
See page 53

7. Metals: left
Non-metal: right
Metalloids
Periodic Table

8. Metals, Non-metals, Metalloids
Due to Mendeleev’s organization, interesting patterns are created, such as the groups: metals, non-metals and metalloids.
See page 55

9. Periods and Families
Each horizontal row in the periodic table is a period
Vertical columns form groups or chemical families
Alkali metals - highly reactive group 1
Alkaline earth metals - group 2, burn
in air if heated
Halogens - group 17, highly reactive non-metals
Noble gases - group 18, stable and unreactive non-metals
See pages

10. Physical Change
Physical changes occur when matter changes in energy or appearance but not its chemical nature.
Physical property changes could include a change in state (ice melting), or size (cutting paper)
But NO new substances are formed

11. Chemical Change
Chemical changes are changes matter undergoes when it becomes new or different matter. To identify a chemical change look for signs such as ______________

12. Chemical changes A compound is composed of at least TWO elements.
How are they made?

13. Bill Nye

14. Video question sheet

15. Bill Nye Chemical Rxns Video
…chemical reactions
Stomach grumbling, metal rusting,
Twice as much. H20 – two hydrogen, one oxygen
The electrons are recombining with other electrons
Energy – can be given off in heat, sound, light..
Chemical bonds
Oxygen and wood/paper make carbon dioxide, water,
Vinegar and baking soda – makes carbon dioxide gas
Metals and salts – copper burns blue

16. Electrons & chemical bonds
Elements with similar electron structure have similar properties.

17. Protons, Electrons and Neutrons
We ALL must be able to calculate the follow: Number of Protons= ATOMIC NUMBER Number of Neutrons= (Atomic mass – atomic number) Number of electrons = can change, electrons move!

18. Protons, Electrons and Neutons
Electrons can move….but for each element the
Number of electrons =
N Number of protons ATOMIC
For Titanium:
Protons= 22
Electron = THE SAME=22
Neutrons= 48-22= 26

19. Lets Practice:
Element
Symbol
Protons
Electrons
Neutrons
Sodium

20. Lets Practice: Oxygen 34 Pb Chlorine Element Symbol Protons Electrons
Neutrons
Oxygen 34 Pb
Chlorine

21. Oxygen Selenium Lead Chlorine Element Symbol Protons Electrons
Neutrons
Oxygen O 8
Selenium Se 34 45
Lead Pb 82
126
Chlorine Cl 17 19

22. Tomorrow: Borh Diagrams

23. Tonight: Review worksheet

24. Tuesday Lab- conclusion Where did elements come from video pbs
Borh diagrams

25. Periodic Table and Atomic Theory
Elements with similar properties have similar electron arrangements Bohr models show electron arrangement in shells
See page
(c) McGraw Hill Ryerson 2007

26. Bohr model patterns
Chemical families on the periodic table have the same number of valence electrons Elements in the same period have the same number of shells Period number indicates the number of electron shells
See page 66

27. Atom Stability
Noble gases are very unreactive because their atoms have filled valence shells. Filled shells make atoms stable. Atoms with filled shells do not easily trade or share electrons.
Other atoms gain or lose electrons in order to achieve the stability of noble gases. Gaining or losing electrons makes atoms into ions.
Metals lose electrons to form positive ions
Non-metals gain electrons to form negative ions
Ions have a similar electron arrangement to the nearest noble gas
Example: Sodium ion (Na+) has 11 protons (11+) and 10 electrons (10-) for a total charge of 1+
See pages

28. Elements & Atoms

29. An atom refresher Matter is anything that takes up space and has mass.
All matter is made of atoms
Atoms are the building blocks of matter, sort of how bricks are the building blocks of houses.

30. An atom refresher An atom has three parts: Proton = positive
Neutron = no charge
Electron = negative
The proton & neutron are found in the center of the atom, a place called the nucleus.
The electrons orbit the nucleus on the electron cloud
Picture from

31. What are elements?
Elements are the alphabet to the language of molecules.
To make molecules, you must have elements.
Elements are made of atoms. While the atoms may have different weights and organization, they are all built in the same way.

32. Bohr Model The Bohr Model shows all of the particles in the atom.
In the center is circles. Each circle represents a single neutron or proton. Protons should have a plus or P written on them. Neutrons should be blank or have an N.
In a circle around the nucleus are the electrons. Electrons should have a minus sign or an e. - + + -

33. Electrons have special rules….
You can’t just shove all of the electrons into the first orbit of an electron.
Electrons live in something called shells or energy levels.
Only so many can be in any certain shell.

34. Electrons have special rules….
You can’t just shove all of the electrons into the first orbit of an electron.
Electrons live in something called shells or energy levels.
Only so many can be in any certain shell.
The electrons in the outer most shell of any element are called valance electrons.

35. So let’s try it…. Li Lithium 3 7 How to draw a Lithium atom
First, look at the Periodic Table
How to draw a Lithium atom
Second, determine the number of protons the atomic number)
Then determine the number of neutrons (Atomic mass – atomic number)
Then determine the number of electrons the atomic number) 3 Li
Lithium 7

36. So let’s try it…. Li Lithium Protons = 3 3 7 Neutrons = 4 (7-3=4) - +
Electrons = 3
2 in the 1st shell, 1 in the 2nd shell
Neutrons = 4
(7-3=4)

37. Lewis Dot Structure O • • • • • •
The Lewis Dot Structure is a bit different from the Bohr model.
It only shows the element symbol and it’s outer most electron shell. + - • O • • •
• •