Transcript Atoms and Molecules with charges

ATOMS AND
MOLECULES
ESSENTIAL QUESTION

How do we distinguish between atoms and
molecules?
Definition of ATOM

is the smallest particle into which an element can be
divided and still be the same substance
What is an Element?

Definition of Element: A substance that cannot be
broken down into other substances by chemical or
physical means.
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
– neutral charge; holds the protons in the
center of the atom (nucleus); largest
 Proton -- positively charged particles; determines the
identity of the element;
 Electron – negatively charged particles; smallest;
rapidly move around the nucleus
WHAT IS AN ATOM MADE OF?
ATOMS

The atom is held together by nuclear forces -- the
positive protons and the negative electron attract
each other.
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.
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.
What’s missing?
Draw an arrow to it and Label
Electrons
Electron
Shell
+
Protons
Nucleus
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.
What are Molecules?
Molecules are very small objects that are
made up of connected atoms
What Do Molecules Look Like?
Molecules can take on all kinds of
different shapes and sizes
Let’s look at a few!
Water
H
H
O
H2O
Air
Nitrogen
N
N
Oxygen
O
O
Sugar
C6H1206
Salt (Sodium Chloride)
NaCl
Do Molecules Move?
Yes, they do!
How do they move?
It depends on whether they are
in a solid, liquid, or gas
Molecule Activity
Molecule Activity

1. Water

2. Carbon Dioxide
Molecule Activity

3. Ammonia

4. Methane