Development of model of atom

Question 1

What did Dalton think?

Answer 1

Thought that atoms were hard spheres and that elements had only one type of atom

Question 2

What did J.J Thompson discover and describe atoms like?

Answer 2

The electron (tiny negatively charged particle) and described
atoms like ‘plum puddings’ with negative charges embedded in a cloud of positive
charge

Question 3

What experiments did Geiger and Marsden’s do and what did this prove?

Answer 3

Fired positive alpha particles at gold foil which showed atoms could not be solid.

Question 4

What did Rutherford propose and what model of the atom did he create?

Answer 4

The positive charge of an atom is in a small centre which he
called the nucleus and electrons orbit this nucleus. ( This is the nuclear model)

Question 5

What did Niels Bohr suggest and when?

Answer 5

In 1914 he suggested electrons orbit at set distances in energy levels ( or shells)

Question 6

What did James Chadwick discover and when?

Answer 6

In 1932 he discovered the neutron which has no charge and has the same mass as a proton