Evolution of the Atom Model

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in the student’s
own handwriting.
Chunk the information on the
right to form questions in this
Describe how the atom model has
progressed through time.
Atomos – Greek word for “cannot be cut” or “indivisible”.
Atoms are the smallest piece of matter that cannot be commonly broken down.
Dalton – Thought all matter was made of particles shaped like simple solid spheres.
 Matter is made from atoms that can be combined.
 Atoms of the same element are exactly the same.
 Atoms of different elements are different.
 Atoms of different elements can be combined to form new substances.
Thomson – discovered electrons and added them to the solid sphere.
Rutherford – discovered empty space and the positively charges nucleus in the center.
Bohr – concluded that the electrons are orbiting around the nucleus in different energy
levels and called them shells.
Electron Cloud Model – most recent model, the electrons are moving around the nucleus in
an area called the electron cloud.
Write a summary about the evolution of the atom model here. Make sure to use
complete sentences and write a full paragraph, not just a few sentences.