Date of birth
When was John Dalton born
September 5 or 6,1766
James Chadwick and his contributions
He discovers the neutrons in atoms
John Dalton’s date of discovery
1803
James Chadwick experiment
He did berilyum experiments. When bombarded by alpha particles, particles were emitted
Who was Democritus
He was an Ancient Greek philosopher, a central figure in the development of philosophical atomism and the atomic theory of the universe
When was J.J. Thomas born
December 18 1856
What did J.J. Thomas contribute to the atom
He believed that atoms are uniform spheres of positively charged matter
J.J. Thomason date of discovery
1897
Neil Bohrs experiment
He did not experiment at all he realized a flaw with Rutherford theory
Democritus’s contributions
He developed the atomic theory of the universe. He theorized that all material bodies are made up of indivisible small atoms.
When was Ernest Rutherford
August 30 1871
What did Ernest Rutherford contribute to the atom
He was known for his gold foil experiment in which he showed the the Stone had a tiny heavy nucleus
Ernest Rutherford date of discovery
1911
Ernest Rutherford’s experiment
Gold foil experiment
When was Neil Bohr born
October 7 1885
What was Neil boars theory of the atom
The hydrogen atoms is based on a quantum theory that energy is transferred
Neil Bohr date of discovery
1913
J.J. Thomas’s experiment
The cathode tube
When was James Chadwick born
October 20 1891
John Dalton contributions to the atom
He claimed that atoms are indivisible and indestructible. All atoms of a given element are identical in mass and properties. A chemical reaction is a rearrangement of atoms.
James Chadwick’s date of discovery
1930
John Dalton’s experiment
His experiments with gasses that led to his discovery on how the atom works
When did Democritus come up with he theory
1430 BC