THE HISTORY OF THE ATOM by Aratz Orozko Iribarren https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4 everything is made of the atom en-us 2023-02-15 09:07:27 UTC 2025-12-23 08:12:06 UTC hello@padlet.com DEMOCRITUS (440 BC) aratzorozko https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483189117

He proposed that matter could not be divided into smaller pieces forever. He said that matter was made of small, hard particles that he called “atoms”. 


]]> 2023-02-15 09:10:21 UTC https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483189117 JOHN DALTON (1803) aratzorozko https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483190177

He created the very first atomic theory. 
All substances are made of atoms. Atoms are small particles that cannot be created, divided, or destroyed. Atoms are invisible.
Atoms join together to make new substances (molecules).


]]> 2023-02-15 09:11:24 UTC https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483190177 JJ THOMSON (1897) aratzorozko https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483191680 He discovered negatively charged particles inside the atom (electrons). 


]]> 2023-02-15 09:12:49 UTC https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483191680 ERNEST RUTHERFORD (1909-1911) aratzorozko https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483193767 ERNEST RUTHERFORD (1909-1911)

He proposed that in the center of the atom is positively charged part called the nucleus. He discovered the protons and nucleus. 


]]> 2023-02-15 09:14:55 UTC https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483193767 NIELS BOHR (1913) aratzorozko https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483196604

He improved on Rutherford's model. He proposed that electrons move around the nucleus in certain paths called energy levels. 
]]> 2023-02-15 09:17:42 UTC https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483196604 SCHRODINGER AND HEISENBERG (1926) aratzorozko https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483197462

He proposed that electrons do not travel in definite paths around the nucleus.


]]> 2023-02-15 09:18:35 UTC https://padlet.com/aratzorozko/w1lzv3jtumq1g0m4/wish/2483197462