The Nucleus

Do you remember the drawing you made of the unknown object during the Warm-Up? How did it compare to what the object actually looked like? The method you used to gather data about your object was very similar to what Ernest Rutherford and others did to explore the structure of the atom.

In this topic, you learned that studies of the atom during the 20th century led to the discovery that atoms are mostly empty space surrounding a dense, positively-charged nucleus. Negatively-charged electrons surround the nucleus. When heavy atoms decay into lighter atoms, they emit alpha and beta rays.