Place the atomic theories in the order in which they were published.

Atoms are made of empty space with electrons around a positively charged mass. The terms nucleus and proton (+) are introduced.

Negatively charged particles are called electrons and are scattered inside a positively charged mass.

Electrons exist in a region around the nucleus called the electron cloud.

Each type of matter is only made up of one type of atom. Atoms are too small to be seen.

Electrons are arranged in energy levels. Lower energy levels are close to the nucleus and higher energy levels are farther away from the nucleus.