Description of Model: Atoms are solid and indestructible.

Experiment: Investigated properties of gases that made him infer that gases must be made of individual small particles that are in constant motion. Combined different gases and substances.

Pros:

• Good theory

• Modern quantitative approach

• Explains the law of chemical combination

Cons:

• Atoms idea with shapes were disproven

• Not a full explanation to other researchers

• Limited information

Conclusions:

• He concluded that all matter is made of

  indestructible and indivisible things called atoms.

• The atoms of a specific element are identical and different elements have different elements

Description of Model: Electrons are surrounded by a positively charge "pudding".

Experiment: He put a vacuum pump to remove all the air in a glass tube and placed a cathode at one end and an anode at another end. He applied high pressure and light from the cathode came out.


Conclusions:  He discovered electrons and proved atoms were divisible.

Pros:

• Big impact on later atomic models.

• First atomic model that introduced electrons to an atomic model.

• Proved Atoms are divisible

Cons:

• Limited explanation on how the "pudding" holds the electrons in.

Description of Model: A nucleus is surrounded by electrons in empty space.

Experiment: He did an experiment where he used gold foil with alpha particles while post-passed.

Conclusions: He concluded that the atom is mostly empty space and that there is a nucleus in the center of the atom.

Pros:

• Discovery of the Nucleus

• Explains unique element traits

• Discovered that the atom is mostly empty space

Cons:

• No explanation on the interaction of electrons.

• Guessed on paths of electrons

  
  

Description of Model: Electrons orbit around the nucleus on "energy levels" or "orbits".

They have fixed positions and energy.

Experiment: Bohr's Model develops it was a quantized orbit around the nucleus and these can only transition between these orbits by absorbing specific amounts of energy


Conclusions: Electrons orbit the nucleus in orbits. They lose energy jumping from one level to another.

Pros:

• Introduces Energy levels

  
  

Cons:

• Limited

• Fails to demonstrate atoms with more than one electron

Description of Model: Electron don't move in waves but sporadic paths around the nucleus.

Experiment: He used a lot of different wave functions to describe the quantum state of a particle which finds electrons in the specific region.

Conclusions:

• He concluded that electrons do not spin in orbits around the nucleus, but rather in a hyperactive path that forms different shapes around the nucleus called orbitals.

Pros:

• Uses math equations that fill in the requirements for determining the behavior of electrons.

• Orbitals

Cons:

• Complexity of imagining electrons as waves

• Uncertainty

Description of Model: In the nucleus there is the positively charge proton and the neutral charged neutron. Electrons surround the nucleus in orbitals.

Experiment: He bombarded beryllium with alpha particals. It caused a reaction which was a type of radiation and while investigating this radiation he determined it was made up of neutral particles similar to protons.

Conclusions: He concluded that neutrons are in the nucleus along with protons.

Pros:

• Discovery of the neutron

• Newer influence on the study of atomic structure

• Use of nuclear physics.

• More enhanced detailed model of the atom

Cons:

• People didn't believe in the neutron

• Concern for the use of radiation

Description of Model: Atoms are different sizes and shapes and are indestructible and indivisible.

Experiment: No experiment, only thinking experiments. He thought that if a stone were cut in half enough times, it would be small enough to be indivisible.

Conclusions:

• He concluded that all atoms are solid, indivisible, and indestructible.

• He said that all matter is made of different types of atoms including different sizes and shapes.

Pros:

• Good foundation

• First Concept

• Showed Diversity

Cons:

• Lack of Evidence

• Simplicity

• Unbelievable