THE HISTORY OF ATOM by Izeia Arregi Etxaniz https://padlet.com/izeiarregi/9cm7gi50whyumoga They are really small (tiny) particles. They are so small that we cannot see them with our eyes. en-us 2023-02-08 11:22:22 UTC 2023-02-14 09:02:13 UTC hello@padlet.com https://padlet.net/icons/png/1f52e.png DEMOCRITUS (440 BC) izeiarregi https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474754512
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”. 


]]> 2023-02-09 09:53:06 UTC https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474754512 JOHN DALTON (1803) izeiarregi https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474759132

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).
]]> 2023-02-09 09:57:06 UTC https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474759132 JJ THOMSON (1897) izeiarregi https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474760676


He discovered negatively charged particles inside the atom (electrons). 



]]> 2023-02-09 09:58:32 UTC https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474760676 ERNEST RUTHERFORD (1909-1911) izeiarregi https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474764326

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








]]> 2023-02-09 10:01:47 UTC https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2474764326 NIELS BOHR (1913) izeiarregi https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2481125857

He improved on Rutherford's model. He proposed that electrons move around the nucleus in certain paths called energy levels. 
]]> 2023-02-14 08:33:05 UTC https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2481125857 SCHRODINGER AND HEISENBERG (1926) izeiarregi https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2481126750

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


]]> 2023-02-14 08:33:56 UTC https://padlet.com/izeiarregi/9cm7gi50whyumoga/wish/2481126750