CHEMISTRY presentation lecture eleven.ppt

About chemistry

1. ATOMS AND
MOLECULES
ICT 2A HUDAYKULIYEV SERDAR
ALLAMURADOV EZIZ

2. ESSENTIAL QUESTION
How do we distinguish between atoms and
molecules?

3. Definition of ATOM
is the smallest particle into which an element
can be divided and still be the same substance

4. What is an Element?
Definition of Element:A substance that
cannot be broken down into other substances
by chemical or physical means.

5. WHAT’S THE BIG IDEA??
Atoms are composed of small particles that
determine the properties of the atom.
There are three types of subatomic particles:
Neutron–neutralcharge; holds the protons in
the center of the atom (nucleus); largest
Proton--positivelycharged particles;
determines the identity of the element;
Electron –negativelycharged particles;
smallest;rapidly move around the nucleus

6. WHAT IS AN ATOM MADE OF?

7. ATOMS
The atom is held together by nuclear forces--
the positive protons and the negative electron
attract each other.

8. ATOMIC MODELS
(Bohr Model)
1. Nucleus--protons and neutrons are in the
center of the atom called the nucleus;
2. Electron Shells--electrons travel outside the
nucleus in "special orbits"; each orbit can only
hold a specific number of electrons.

9. ATOMIC MODELS
(Bohr Model)
FOR EXAMPLE:
Orbit #1 (closest to the
nucleus) can hold only
two (2) electrons.
Orbit #2 can hold up to
eight (8) electrons.
Orbit #3 can hold up to
eight (8) electrons.

10. What’s missing?
Draw an arrow to it and Label
Electron
Shell
Nucleus
Electrons
Protons
+

11. ATOMIC MODELS
(Modern Atomic Model)
1. Nucleus-protons and neutrons are in the
center.
2. Electron Shells--a region around the nucleus
of an atom where electrons are likely to be found.

12. Molecules are very small objects that
are made up of connected atoms
What are Molecules?

13. What Do Molecules Look Like?
Molecules can take on all kinds
of different shapes and sizes
Let’s look at a few!

14. H H
Water
O H
2O

15. Air
O O
NN
Nitrogen
Oxygen

16. Sugar
C6H1206

17. Salt (Sodium Chloride)
NaCl

18. Do Molecules Move?
Yes, they do!
How do they move?
It depends on whether they are
in a solid, liquid, or gas

19. Molecule Activity

20. Molecule Activity
1. Water 2. Carbon Dioxide

21. Molecule Activity
3. Ammonia 4. Methane