1.  Hydrogen  Helium  Strontium  Copper  Rubidium  Iodine  Silicon

2.  Smallest unit of matter that retains properties of an element  Made up of protons, neutrons, and electrons

3.  A classification of atoms based on number of protons  All atoms of the same element act/react the same way  If they all have the same number of protons, how might they be different?

4.  Atoms of the SAME element with different numbers of neutrons  Example: Carbon-12 and Carbon-14  Both are carbon (both have 6 protons!)  Carbon-12 has a mass of 12; carbon-14 has a mass of 14  How many neutrons does each one have?  Which one do you think is more common? Why?

5.  Two or more atoms of different elements bonded together  Fixed ratio  Requires a chemical reaction to create (put together) or destroy (take apart)  Molecule : any single piece of a compound, OR two or more atoms of the same element bonded together  All compounds are molecules but not all molecules are compounds.

6.  Two or more elements or compounds mixed together but NOT chemically bonded  Not in a fixed ratio  Can be separated without chemical processes

8. 1. How did you figure out the number of electrons in each atom? 2. How did you figure out the number of protons in each atom? 3. How did you figure out the number of neutrons in each atom? 4. How did you figure out the mass of each atom? 5. How does the mass of each atom compare to the average atomic mass of the element given in the periodic table?

9.  Electrons are in a calcium atom?  Protons are in a zinc atom?  Neutrons are in a sulfur atom with mass of 32 AMU?  Total protons are in a molecule of NaCl?  Total protons are in a molecule of H 2 O?