Atomic Model : Sarah Ganger

Democritus

Oct 28, 1000

What
He thought that all matter consisted of extremly small particles that cannot be divided.
How
He thought his ideas out with Aristotle in 500 BC

Aristotle

Oct 28, 1000

What
He had the idea of a structure of matter
How
He thought his ideas out with Democritus in 500BC.

Issac Newton

Oct 31, 1704

What
Proposed a mechanical universe with small solid masses in motion

John Dalton

May 24, 1803

What
All matter consisted of extremely small particels that cannot be divided
How
Dalton measured the mass of elements that combine when compounds form

Dmitri Mendeleev

Oct 31, 1869

What
Arranged elements into 7 groups with similar properties. He discovered that the properties of elements "were periodic functions of the their atomic weights". This became known as the Periodic Law

Joseph John Thomson

May 24, 1897

What:
Thomsond thought that things with opposite attractions attrack each other.
How:
his experiment had one disk a each end of a tube. Wires connected each disk to a source of electric currents. When the current is turned on, one disk becomes negative charged ,and the other becomes positively charged. Aglowing space appears between the disk.

Ernest Rutherford

Oct 28, 1899

What
He believed that uranium enits have fast- moving particels that have a positive charge.
How
He had an atom with an evenly spaced mass with positive charges.

Hantaro Nagaoka

Oct 31, 1904

What:
He suggested that an atom has a central nucleus.
How
He had an image that electrons move in orbit like the rings around Satur

Erwin Schrodinger

Oct 31, 1926

What:
He developed mathmatics equations to describe the motion of electrons in atoms.
His work lead to the electrron cloud model.

James Chadwick

Oct 31, 1932

What
He confirms the existences of neutrons, which have no charge.
How
Atomic nuclie contained neutrons and psitively charged protons.

Louis de Broglie

Oct 31, 1942

What:
Louis proposed that moving particels like electrons have some properties of waves.

Niels Bohr

Oct 28, 2011

What
He thought that his idea and Rutherfords were the same, but his had a nuclrus surrounded by a large volume of space.
How
Bohrs modle focoused on the electrons movement with constant speed with a fixed odit around the nucleus.