3. Everything that we come in contact with is made up of MATTER. * books * food * air * sound (???) No, this is energy.

4. Matter is made up of tiny particles that are in constant motion called ATOMS. * Kinetic Molecular Theory

5. Atomic Theory Atoms are the building blocks of all matter. * atoms are the smallest thing in MATTER

6. ATOM Means “indivisible” or “indestructible” or “unbreakable”.

7. Atoms have smaller particles inside them known as Subatomic Particles.

8. Subatomic Particles Protons ( + charge ) Neutrons ( no charge / neutral ) Electrons (- charge )

9. Subatomic Particles Subatomic particles no longer carry the properties of the original matter (atoms).

10. * Each subatomic particle has a set location in the atom. PROTON NEUTRONNUCLEUS ELECTRONLocated in the electron cloud.

11. Democritus / John Dalton * The atom was similar to a billiard ball. ( solid and indestructible)

12. J.J. Thomson * The atom was similar to a blueberry muffin.

13. Ernest Rutherford * The atom is mostly empty space with a dense positive center. electrons moving in orbits around the center. similar to the solar system

14. Niels Bohr * The atom is similar to a multilevel office building. (electrons exist on different floors and can jump from one floor to the next.)

15. Present Day Model * Is called the Electron Cloud Model. (we do not know exactly where the electrons are located at any given time) * AKA; Quantum Mechanical Model

16. * Atoms in nature are NEUTRALLY charged. For every PROTON there is an ELECTRON. For every POSITIVE charge there is a NEGATIVE charge. ** P = E **

17. Atomic Number Equals the number of protons found in an atom’s nucleus. * also tells how many electrons are in the electron cloud

18. The atomic number is used to identify the type of atom. * change the number, and you change the atom you are referring to * it is like a person’s social security number

19. Ultimately, the identification of an atom comes down to the number of protons found in its nucleus.

20. Element A substance that is made up of only one type of atom. * gold * silver * copper

21. Chemical Symbol An abbreviated way to write the name of an element.

22. Chemical Symbol The first letter of the name is always used. (capitalized) * carbon = C : oxygen = O : sulfur = S Could be a combination of the first letter and another letter from the name. (2 nd letter is lower case) * helium = He : radon = Rn : magnesium = Mg

23. Chemical Symbol Sometimes their symbol comes from their original Latin names. * gold = Au : silver = Ag mercury = Hg : lead = Pb

24. Energy Levels Various locations within the electron cloud where electrons are arranged. * like seats around a stage * front rows fill first * rows need to be filled

26. Each energy level has a certain number of electrons that will fit in it. As you move from one energy level to the next, away from the nucleus, the maximum number of electrons that will fit increases.

27. Energy levels closest to the nucleus have a low energy state. Energy levels farthest from the nucleus have a high energy state.

28. Example of Potassium’s Energy Levels K

29. Example of Chlorine’s Energy Levels Cℓ