Unit 22.Atomic physics

04.14.2020
08:48:21
Dear students, good morning
Today's topic : 22.atomic physics - nuclear atom
Pg.no : 309 to 311
The important points are
1.atomic structure first explained by Ernest Rutherford in 1910 .- solar system model.look at figure 22.3
2. He discovered that every atom has a tiny central nucleus.
3.In 1896 J.J Thomson gave rise to Plum pudding model of an atom in figure 22.4
4.in that electrons ( negatively charged) form the plums stuck in a spherical pudding ( positively charged)
5. In next experiment - Rutherford scattering - alpha particle in figure 22.5
6.From the experiment he realised
* Most alpha particles ( positively charged) pass straight through gold foil..- a lot empty space in an atom
* Some alpha particles are back - scattered - so atoms centre part of positive charge.and it's very small that is nucleus
No homework
For better understanding of concepts watch the below videos