Explain how these photos are related on your paper: IN CHEMISTRYOPPOSITES ATTRACT TOO!! All matter has an electrical nature After dragging your feet across carpet, what happens when you reach out to touch something or someone? Why does rubbing a balloon on your head make your hair stick to it? Lets find out.leclab/ballrub.htm The electrical properties of matter can be summed up like this *Like Charges Repel Each Other *Opposite Charges Attract Every uncharged atom contains. Equal number of protons and electrons Protons have a positive charge Electrons have a negative charge Most atoms also have one or more neutrons. Neutrons have are neutral or no charge see where the name comes from? The glue that holds matter together. The sticky force that holds matter together is called chemical bonding. One kind of bonding is caused by positive/negative attraction Another type of compound Ions = electrically charged atoms or groups of atoms. When an atom gains an electron it becomes a negative ion. When an atom losses an electron it becomes a positive ion. IN OUT Quick charge practice Ill give you the number of protons, electrons, or neutrons you tell me the charge ex: 7 protons = charge of electrons = 2. 6 protons = 3. 5 neutrons = 4. 2 electrons = protons = Doing the math Sodium Ion 11 Protons ( Has a charge of +11) + 10 Electrons (Has a charge of -10) _____________________________________ (Has a total charge of _______ ) = Na + More math Chloride Ion 17 Protons ( Has a charge of +17) + 18 Electrons (Has a charge of -18) _____________________________________ (Has a total charge of _______ ) = Cl - IONIC COMPOUNDS = Substances composed of positive and negative ions. It has no electrical charge Ex : Na + + Cl - = NaCl The charges have canceled each other outjust like in math!! NaCl (Salt) up close and personal NATURE TABLE MOLECULAR THIS IS THE MODEL OF NaCl .CAN YOU TELL WHY IT IS AN IONIC COMPOUND? DRAW ME IN YOUR NOTES!!! HINT: THINK ABOUT CHARGE 6 negative charges from Cl - and 6 positive charges from Na + = IONIC COMPOUND WITH NO CHARGE Give them some names Anion= Negatively Charged Ion Ions.. *Can be a single atom like a sodium cation or chloride anion. *Can be a polyatomic ion (poly means many) = group of ions bonded together ex// NO 3 - List of ions. WHICH ONES IN THIS LIST ARE POLYATOMIC IONS?? Naming monoatomic ions (Remember mono means one) *Cations are metals taking the name of the element. ex// Sodium Ion *Anions drop the last few letters and end with -ide. ex// Chlorine becomes Chloride Ion