1.Dalton

2.Thomson

3.Rutherford

4.Bohr

1.Dalton's Atomic Theory

-All matter is made of atoms. Atoms are indivisible and indestructible.

-All atoms of a given element are identical in mass and properties

-Compounds are formed by a combination of two or more different kinds of atoms.

-A chemical reaction is a rearrangement of atoms

2.Plum Pudding

-An atom consists of a sphere of positive charge with negatively charged electron embedded in it,

 -The positive and the negative charges in an atom are equal in magnitude, due to which an atom is electrically neutral. It has no over all negative or positive charge.

3.

-Protons in the nucleus and the electrons orbited around the nucleus.

4.

-Electrons orbit the nucleus in orbits that have a set size and energy

-The energy of the orbit is related to its size. The lowest energy is found in the smallest orbit

-Radiation is absorbed or emitted when an electron moves from one orbit to another.

Most-empty space.

The rest-positively charged nucleus of protons and neutrons surrounded by negatively charged electrons.

The center-nucleus

The range of characteristic frequencies of electromagnetic radiation that are readily absorbed and emitted by an atom.

The atomic spectrum of each chemical element is unique and is largely responsible for the color of matter. Atomic spectra can also be analyzed to determine the composition of objects.

Diamagnetic v. Paramagnetic

diamagnetic is an element with no unpaired electrons

ex. Neon is 2s2 2p6 so it is diamagnetic

Paramagnetic is an element with unpaired electrons

ex.oxygen is 2s2 2p4(unpaired e- according to Hund's rule)