The development of the model of the atom

Niels Bohr

________ adapted the nuclear model by suggesting that electrons orbit the nucleus at specific distances and they were held in shells.

ball of positive charge

The plum pudding model suggested that the atom is a(n) ________ with negative electrons embedded in it.

Scientists fired **-----------**Their idea was if the positive charge was **----- ------ -----,** the particles ----- ---- - ---- ---- -- ----

Scientists fired **positively charged particles into a thin sheet of gold.**Their idea was if the positive charge was **generally spread out,** the particles s**hould pass the sheet of gold**

* The results from the alpha particle scattering experiment led to the conclusion that **the mass of an atom was concentrated at the centre** (nucleus) and that the **nucleus was charged**. Some particles **were deflected to the side.** This told the scientists that the centre of the atom must be p**ositively charged and that repelled the alpha particles.**