1. CHEMISTRY!

2. Chemistry - Video
Chemistry – The study of matter and changes in matter
Matter – Anything that has a mass and occupies space

3. Compounds – Two or more elements combined. Ex: H2O or NaCl

4. Element – Pure substance made from one sort of atom. Ex: H or O

5. Atom – The smallest unit of matter

6. Five parts to an atom:
Nucleus – the centre of the atom – contains neutrons and protons.
protons – Positive charge (+)
neutrons – No charge or neutral (0)
electrons – Negative charge (-)
Electron shell – the region around the nucleus where the electrons are found.

7. The Periodic Table

8. Pre-Periodic Table Chemistry …
…was a mess!!!
No organization of elements.
Difficult to find information.
Chemistry didn’t make sense.

9. Dmitri Mendeleev Father of the Periodic Table
WHAT HE DID…
Put elements in rows by increasing atomic weight
Put elements in columns by the way they reacted.
SOME PROBLEMS…
He left blank spaces for what he said were undiscovered elements.
He broke some patterns

10. A: Atomic number = number of protons
B: The elements charge
C: The elements symbol
D: The name of the element
E: Atomic Mass or the number of protons and neutrons

11. Atomic number - # of protons
Atomic Mass – Mass of protons and neutrons
So… how do you calculate the number of neutrons?
Atomic Mass – Atomic number = # of neutrons!
Number of Electrons equals the number of protons in a neutral atom.

12. Notes – Chemistry Introduction
Sheet to complete: Atomic Structure Worksheet

13. The Periodic Table

14. A: Atomic number = number of protons
B: The elements charge
C: The elements symbol
D: The name of the element
E: Atomic Mass or the number of protons and neutrons

15. The Periodic Table
Groups
Periods

16. Period: indicates the number of shells of an element

17. Group/family: indicates the number of electrons on the valence shell

18. Group 1 – Alkaline metals
The most reactive group of elements
Reactivity increases as you move down the group
Cs and Fr are liquids; all others are solid

19. Group 2 - Alkaline Earth Metals
Reactive but not as reactive as the Alkaline metals
Several of these elements are important mineral nutrients (such as Mg and Ca)
All are solids

20. Group 3 – 12 – Transition Metals
Less reactive metals
Not as predictable as other metals
Have a wide variety of properties
Hg is the only liquid; all others are solid

21. Group 17 - Halogens Very reactive nonmetals
Fluorine is the most reactive
this decreases as you move down the group
F and Cl are gas; Br is liquid; I and At are solid

22. Group 18 – Noble Gases
Extremely low chemical reactivity or inert (very stable)
Used in common items such as neon signs or balloons
All are gas

23. Lanthanides & Actinides
Lanthanides: atomic numbers 57 – 71 (top row)
Actinides: atomic numbers 89 – 103 (bottom row)
All solid

24. Metals, Nonmetals, and Metalloids
6.1
Metals, Nonmetals, and Metalloids

25. Metals To the left of the staircase line
Physical Properties:
Luster (shiny)
Good conductors
High melting point
Solids at room temperature (mercury is an exception)
Chemical Properties:
Easily lose electrons
Corrode easily
(rusting or tarnishing)

26. Non-metals to the right of the staircase line
Chemical Properties:
Tend to gain electrons
Physical Properties:
Dull (not shiny)
Poor conductor of electricity
Brittle
Low Melting Point

27. Metalloids along the staircase line
Solids
Shiny or dull
Conduct heat and electricity better than non metal but not as well as metals

28. Notes – The Periodic Table
Sheet to complete: The periodic table

29. Electron Shell Diagram (Bohr-Rutherford)
Period: Indicates the number of shells or energy levels of the element

30. Electron Shell Diagrams – Bohr-Rutherford

31. Electron Dot Diagram (Lewis Diagram)
Group/family: indicates the number of electrons in the outer shell (valence shell)

32. Practice!
Electron Dot Diagram – Lewis diagram

33. Electrons on the Move!
The goal of every atom is to become stable like the Noble Gases.
There are three ways this can be accomplished:
Lose electrons
Gain electrons
Share electrons

34. Remember Valence Electrons?
What are they?
Electrons on the last shell or energy level of the atom
How many valence electrons around each of these elements? Na S Br Ne

35. Ions
Ions are an atom or a group of atoms that have a positive or negative charge.
An ion is formed when atoms lose or gain electrons
There are two types:
Cation – a positively charged atom caused by a neutral atom losing one or more electrons
Anion: a negatively charged atom caused by a neutral atom gaining one or several electrons.

36. Metals form cations because they lose electrons easily
Metals form cations because they lose electrons easily. Therefore their charge is positive.
How many electrons will the following metals lose? Na Mg B
Non metals form anions because they gain electrons. Therefore their charge is negative.
How many electrons will the following non-metals gain? N O F Ne
After losing or gaining electrons, their valence shell is full and therefore stable.

38. Ex: N
is a non-metal and in group 15, therefore it has to gain 3 electrons to become the anion N3- .
Ex: O
is a non-metal in group 16, therefore it has to gain 2 electrons to become stable. It will become the anion O2- .
Ex: Na
is a metal in group 1, therefore it has to lose 1 electron to become stable. It will become the cation Na+.

40. To Do: Animation: What are ions? Notes: Ions Practice Sheets
Ions Sheet Review
Electrons on the move