Development of Atomic Models

Flashcards covering the history and key features of atomic theories and models proposed by Dalton, Thompson, Rutherford, and Bohr.

What discovery helped John Dalton develop his idea about the structure of atoms?

He discovered that elements always combine in specific amounts to form compounds.

How did John Dalton describe atoms in his solid sphere model?

Each element has atoms of a specific mass in the form of solid spheres that cannot be divided further.

In what year did J.J. Thompson propose the plum pudding model?

1897

How did J.J. Thompson's plum pudding model describe the atom?

Atoms are made of a positively charged sphere with tiny negatively charged electrons scattered throughout.

What did Rutherford's gold foil experiment reveal about the atom in 1911?

It revealed that atoms have a small, dense nucleus.

What observed result during Rutherford's gold foil experiment indicated the presence of a nucleus?

Some particles bounced back when fired at a thin sheet of gold.

How did Ernest Rutherford describe the atom in his Nuclear Model?

The atom has a small, dense nucleus at the center, with electrons orbiting around it, mostly in empty space.

What atomic model did Niels Bohr introduce in 1913?

The Planetary Model

According to Niels Bohr's Planetary Model, how do electrons move around the nucleus?

Electrons orbit the nucleus in fixed paths or energy levels, explaining atomic stability.