1. Atoms, Elements, Periodic Table
S8P1a: Distinguish between atoms and molecules
S8P1f: Recognize that there are more than 100 elements and some have similar properties as shown on the Periodic Table of Elements
S8P1g. Identify and demonstrate the Law of Conservation of Matter

2. Elements

3. down into simpler substances by physical or chemical means.
An element is
a pure substance
that cannot be broken
down into simpler substances
by physical or chemical means.
Elements are the ingredients that make up everything that exists

4. 2) A pure substance is one that has only one type of particle.
Elements are pure because
each atom with the same atomic number (same number of protons) belongs to the same element.

5. 3) One particle (or piece) of an element is called an atom.
All atoms with
the same number
of protons (atomic
number) belong to
the same element.

6. 4) Elements can be identified by properties that don’t
change no matter
the size of the
substance
things like:
boiling point,
melting point,
density and
reactivity –
these are the
characteristic properties

7. Atoms are made of elements right
Atoms are made of elements right? Turn to your neighbor to defend why or why not…
30 seconds…. GOOOO!!!
Atoms
Elements

9. An atom is the smallest part of an element that still has the properties of that element.
(the smallest part of “stuff” that is still “stuff”)

10. 2) Particles that make up an atom: a) protons: positively charged (+1)
b) Electrons: negatively charged (-1)
c) Neutrons: NO charge (+1 -1 = 0)
Two hydrogen atoms are walking along the street. One suddenly goes: - Oh shoot, I´ve lost an ' electron! Other one says: -Are you sure? –
Yes, he replies.- -I'm positive.

11. b) Electrons circle the nucleus in the electron cloud
3) Protons and neutrons are gathered together in the center of the atom called the nucleus
b) Electrons circle the nucleus in the electron cloud
Electron cloud
nucleus

12. -this is called the atomic number
4) Atoms differ from one another because of the number of protons in the nucleus.
-this is called the atomic number
(all atoms with the SAME atomic number belong to the same element)

13. Tell me . . .
1) What are the three particles that make up an atom?
2) What is the center of an atom called?
3) What makes one type of atom different from another?

14. Periodic Table

15. Periodic Table of Elements
1) Elements are organized on the
Periodic Table of Elements
by atomic number.

16. 2a) Periodic Table
-columns are called groups or families because elements in a group behave alike or have similar properties

17. 2b) Periodic Table – cont:
Rows are called periods:
Elements show a gradual change in properties across a period.
                                                                                                                                                                           

18. 3) Elements can be divided into three types: metals, nonmetals, and metalloids; these categories are based on how the element behaves.

19. gold, silver, iron, sodium, calcium location on table: left and middle
3a) Metals:
properties:
shiny, good
conductors,
ductile, malleable
examples:
gold, silver, iron, sodium, calcium
location on table:
left and middle
Have students come up with properties – these should include: shiny, good conductors, ductile, malleable

20. dull/not shiny, not malleable, not ductile, poor conductors, brittle
3b) non-metals:
properties:
dull/not shiny, not malleable, not ductile, poor conductors, brittle
examples:
carbon
sulfur
oxygen
location on table:
far right
Have students come up with properties: should include dull/not shiny, not mallable, not ductile, poor conductors, brittle

21. 3c) metalloids:
properties:
moderate conductors – also called semiconductors
properties of both metals and nonmetals
examples:
Silicon
location on table:
on the “Stair-step” line on the right

22. 4) If you know the category, you know the properties,
and for an unknown element, if you know the properties you can figure out the category.

23. Name the three categories of elements found on the Periodic Table.
How are periods and groups on the Periodic
Table different?