1. Atoms
Their structure and the properties
of elements
An element smallest posible piece…
Miss Sofia Paz

2. First: Different elements or compounds have different properties:
States (luquid, solid, gas, plasma) this properties depend on the atoms of the elements!
MADE UP OF
SUBATOMIC
PARTICLES:
-PROTONS(+)
-NEUTRONS
-ELECTRONS(-)
ATOM:
Smallest possible piece of
an element (without loosing
their properties)

3. The attraction of the
negatively charged
electrons and the
positively charged
protons keeps the
electrons close to
the nucleus.

4. How this subatomic particles form an ATOM?
-NUCLEOUS: NEUTRONS, PROTONS(+),
-CLOUD OF ELECTRONS (-)
The attraction of the
negatively charged
electrons and the
positively charged
protons keeps the
electrons close to
the nucleus.
Electrons have less
mass than neutrons
and protons.

5. NOT constantConstant
ATOMIC NUMBER (Z)( NUMBER OF PROTONS)
# of # of
The number of
protons is constant
in each element
The atom is
electrically neutral,
positive charges are
balanced with
the negative charges.
NO two
elements have
the same
atomic number
the number of protons = the Atomic Number(Z)

7. ISOTOPES (when the number of neutrons change)
Alternate forms of elements (always same proton number but
different neutron number)
Why C14, C13, C12??? Is the NUCLEAR NUMBER: NUMBER OF
PROTONS + NUMBER OF NEUTRONS

8. RADIOACTIVE ISOTOPE:
HOMEWORK FOR NEX CLASS! What are radioactive
isotopes and What uses does they have?
CONCEPT :CHEMICAL PROPERTIES ARE BASED ON STRUCTURE OF ATOMS

9. ElECTRONS AND REACTIVITY:
Electrons properties: -amount of energy
-how thigly they are held by protons
Depending on this properties electrons belong to differents energy
leves:
I energy level can hold up to 2 electrons
II energy level can hold up to 8 electrons
III energy level can hold up to 18 electrons
HOW DOES ATOMS STRUCTURE DETERMINE HOW IT REACTS??

11. CONCEPT :CHEMICAL PROPERTIES ARE BASED ON STRUCTURE OF ATOMS
I energy level :2 electrons
II energy level: 8 electrons
III energy level : 18 electrons

12. ATOM SONG! 3.21 MIN
 https://www.youtube.com/watch?v=O5iaw5WNuB0

13. CONCEPT :CHEMICAL PROPERTIES ARE BASED ON STRUCTURE OF ATOMS
Element/
isotope
Atomic
Number
Protons Neutrons Total
electrons
(same number
ofprotons+)
Electrons in
the highest
level
12C 6
14C
14N 7
16O 8
P 15 15
S 16 16

14. Just howsmall is an atom??
 http://www.youtube.com/watch?v=yQP4UJhNn0I
 DOGS TEACHING CHEMSITRY
 http://www.youtube.com/watch?v=addK0b2Isw8