Developing Models of the Atom Flashcards

All 6 cards in this deck

Describe the plum pudding model of the atom.

A ball of positive charge with negative electrons embedded in it, like plums in a pudding.

What were the three observations in Rutherford's alpha particle scattering experiment?

Most alpha particles passed straight through the gold foil, a few were deflected, and a very small number bounced back.

What did most alpha particles passing straight through the gold foil show about the atom?

That the atom is mostly empty space.

What did the very small number of alpha particles deflected back through large angles show?

That the positive charge and nearly all the mass are concentrated in a very small, dense nucleus.

What did Bohr add to Rutherford's nuclear model?

That electrons orbit the nucleus at set distances (fixed energy levels), not at any distance.

Give one limitation of modelling alpha scattering by rolling marbles down a slope past a weight.

The marble and weight have no charge (also: the model is 2D, not to scale, and marbles only deflect on contact).