Transcript Describe the structure of matter in terms of atoms and molecules

I:I Understand the
structure of matter
1. What is a model and how do
scientists use them?
• Reality is complex.
• Study as a whole.
• Make predictions.
• Only a
representation.
2. How small is an atom?
a. The width of one hair is one million atoms.
b. An atom is as small as a cell.
c. You can see atoms through our classroom microscopes.
3. What do scientists use
models for?
4. How are models limited in
how they present information?
5. What did previous scientists
do and what were their
contributions to help develop
the atomic theory and our
• ..
current model of an atom.
Scientists add to theory of atom
Democritus 450 BC
Uncuttable = ‘atomos’
Aristotle 350 BC
Setback for 2000 years
Dalton 1800
Gas experiments showed
that tiny particles combine.
Thomson 1897
Vacuum tube showed
negative charges.
Rutherford 1899
Gold Foil experiments
found nucleus.
Bohr 1913
Fixed energy levels.
6. What is the electron cloud?
7. Where are the following
located:
• a. nucleus
• b. electrons
• c. neutrons
• d. protons
8. What is a periodic table?
9. Who is Dimitri Mendeleev &
what did he do?
10. What is the difference between
(a)molecules & (b)compounds?
Hydrogen
H2
Oxygen
02
Nitrogen
N2
Water
H20
Carbon Dioxide
C02
Methane
CH4
11. What are the main properties of
solid, liquid and gas?
(a) No definite shape, but definite volume.
(b) No definite shape, no definite volume.
(c) Definite shape, but definite volume.