1. Atomic Structure

2. What are the 3 major parts of an atom? Proton Neutron Electron

3. Draw a diagram showing the location of each part of the atom.

4. Draw a Diagram of an Atom

5. What is the Nucleus? The nucleus is the central part of an atom. It is composed of protons and neutrons. The nucleus contains most of an atom's mass. **IMPORTANT!** It was discovered by Ernest Rutherford in 1911.

6. What is a Proton? Protons are positively charged particles found in the atomic nucleus. Protons were discovered by Ernest Rutherford.. Quarks make up the proton –2 “down” quarks & 1 “up” quark

7. What is a Neutron? Neutrons are uncharged particles found in the atomic nucleus. Neutrons were discovered by James Chadwick in 1932. Quarks make up the neutron –2 “up” quarks & 1 “down” quark

8. What is an Electron? Electrons are negatively charged particles that surround the atom's nucleus. Electrons were discovered by J. J. Thomson in 1897. *remember the “plum pudding” model? Electrons determine properties of the atom. Chemical reactions involve sharing or exchanging electrons.

9. What is an Isotope? Atoms that have the same number of protons but different numbers of neutrons

10. Hydrogen has three Isotopes.

11. What is the Electron Cloud Model?

12. Model of the atom pictures the electrons moving around the nucleus in a region called an electron cloud. The electron cloud is a cloud of varying density surrounding the nucleus. The varying density shows where an electron is more or less likely to be. Atoms with electrons in higher energy levels have additional electron clouds of different shapes.

13. What is the Electron Cloud Model? Diagram 1:

14. What is the Electron Cloud Model? Diagram 2:

15. What is the Electron Cloud Model? More diagrams