Term
Aristotle's Contributions |
|
Definition
Gave basic idea of atom
added qualities (heat, light, cold, moisture)
Thought all matter was made of four elements (Earth, water, fire air) |
|
|
Term
Democritus' Conrtibutions |
|
Definition
Greek Philosopher
Idea of 'atomos' (indivisible)
No experiments to support idea |
|
|
Term
|
Definition
No protons, electrons, or nuetrons
Solid and Indestructible
|
|
|
Term
|
Definition
Conservation of Mass-
Mass is neither created nor destroyed during basic chemical reactions
|
|
|
Term
|
Definition
Law of Definite Proportions-
The fact that a chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample or source of the compound |
|
|
Term
|
Definition
Law of Multiple Proportions-
If two or more different compounds are composed of the same two elements, then the ratio of the masses of the second element combined with a certain mass of the first element is always a ratio of small whole numbers
D(all)(ton)- All of the proportions/ tons of proportions=
Law of MULTIPLE Proportions |
|
|
Term
John Dalton's Atomic Theory of Matter
|
|
Definition
All matter is made of atoms (atoms are indivisible and indestructable)
All atoms of a given element have identical masses and properties
Compounds are formed by a combination of two or more different kinds of atoms (Law of Constant Proportions)
A chemical reaction is a rearrangement of atoms |
|
|
Term
|
Definition
He knew that...
Atoms of any element can be made to emit tiny negative particles
ALL atoms must contain these negative particles
Atoms do not have a negative net charge so there must be something balancing the negative charge
|
|
|
Term
|
Definition
Set up so electric current runs through a tube
light moves from positive end to negative end
When magnets were added the light bent, and still went from + to -
Showed that....
- and - repel
- and + attract
Showed negative charge in atom called electron |
|
|
Term
William Thompson
(Lord Kelvin)'s
Theory
|
|
Definition
Negative Electrons Were Embedded into a positively charged spherical cloud
|
|
|
Term
|
Definition
Plum Pudding Model
(positive cloud, negative electrons) |
|
|
Term
Earnest Rutherford's Experiment |
|
Definition
Gold Foil Experiment
What he Expected: Actual Results:
The particles to pass through Most passed through
without much change in direction because the atom is
because the positive charges mostly empty space
were spread out evenly but some were deflected
|
|
|
Term
Conclusions of the Gold Foil Experiment |
|
Definition
Atom mostly empty space
Nucleus has + charge
Electrons float around the nucleus |
|
|
Term
Rutherford's Model of the Atom |
|
Definition
Dense nucleus made of protons and nuetrons
Electrons orbit the nucleus |
|
|
Term
|
Definition
Electrons had a distinct orbit around the nucleus
Looks like the Jimmy Neutron logo
nucleus in the middle
electrons orbit the nucleus on the energy fields |
|
|
Term
|
Definition
Charge- Cloud Model
electrons occupy orbitals around the nucleus determined by their energy levels |
|
|