1. Atoms & The Periodic Table of the Elements

2. Atoms What are the three parts of the atom? What are the charges of the three different parts?

3. Particles in an Atom ParticleSymbolChargeRelative Mass (amu) Protonp+p+ 1+1 Neutronn01 Electrone-e- 1-1/1,836

4. Atomic Number Every atom of a given element has the same number of protons The number of protons in an atom of a certain element Ex: Carbon’s atomic number is 6

5. Isotopes Atoms of the same element with different number of neutrons is called an ISOTOPE Carbon-12: 6 neutrons Carbon-13: 7 neutrons Carbon-14: 8 neutrons An isotope is identified by the mass number (sum of mass of protons & neutrons)  Carbon-14 would have a higher mass number than carbon-12 because it has two additional neutrons

6. Isotopes (Continued)

7. Periodic Table Why do we have the periodic table? How are elements organized on the periodic table?

8. How to Read the Periodic Table Periods—horizontal rows Groups—vertical columns

9. Finding the Number of Protons, Electrons, and Neutrons Atomic number=protons Atomic mass=number of protons & neutrons How do we find the neutrons? Atomic mass-Atomic number=# of neutrons How do we find the number of electrons?

10. Metals Good conductors of electric current & heat Tend to be shiny & bendable Some are magnetic

11. Reactivity of Metals Usually lose electrons to other atoms to react with them Some metals are very reactive while others react very slowly Corrosion—gradual wearing away of a metal due to a chemical reaction

12. Different Types of Metals Alkali Metals Group 1  React with other elements by losing an electron  So reactive that they are never found as uncombined with other elements in nature—found only in compounds! Alkaline Earth Metals Group 2  Not as reactive as alkali metals but more so than most metals  React with other elements by losing 2 electrons  Like Alkali metals, they are never found uncombined in nature Transition Metals Group 3-12  Shiny and hard metals  Good conductors of electric current  Less reactive than the other two types of metals but still rarely found uncombined in nature Metals in Mixed Groups some elements in Group 13-15  Never found uncombined in nature

13. Synthetic Elements Atomic numbers 92 and higher Created by scientists—never found naturally occurring Several means to create these elements  Combine nuclei of atoms of different elements  Bombard nuclei with neutrons

14. Nonmetals Most are poor conductors of electric current and heat Solids are dull and brittle Carbon, Iodine, and Sulfur are solids at room temperature Bromine is a liquid at room temperature

15. Inert Gases Group 18 are inert gases Unreactive—generally do not gain or lose electrons to form bonds Also known as noble gases

16. Semimetals Some properties of metals but some properties of nonmetals All are solids at room temperature Brittle, hard, and somewhat reactive Varying ability to conduct electricity—can conduct electric current under some conditions but not at others Used to make computer chips and lasers