Presentation on theme: "How do compounds form? Bonding Knowledge Rating Know it! Think I know it! NO Clue ! KI TKI NC Valence electrons Electron dot structures Octet rule Anion."— Presentation transcript:
How do compounds form? Bonding
Knowledge Rating Know it! Think I know it! NO Clue ! KI TKI NC Valence electrons Electron dot structures Octet rule Anion Cation Ionic Bond Metallic Bond Halide ion Write your own definition of each term!
4 things can happen when elements come together to form compounds? 1. Atoms can lose electrons 2. Atoms can gain electrons 3. Atoms can share electrons 4. Share pooled electrons
Jerry Springer Chemistry Sick, Sick, Sick!!
Otherwise known as Ionic Bonding Metals are easy- 1. give up valence electrons 2. become positively charged Nonmetals are users 1. take valence electrons whenever possible 2. become negatively charged
First- Let’s draw the Bohr model for Na and Cl How many valence electrons does each element have? What happens when the metal looses his electron? What happens when Cl gains and electron?
What do we know about the stability of Nobel gases ? Octet rule- atoms in compounds tend to have the electron configuration of a nobel gas. A Really Long Song...
Want to learn an easier way of drawing valence electrons around atoms? Lewis Dot structures- Write the symbol and the electrons (in their correct spots!) Let me show you sodium and chlorine!
Now you try 1. Magnesium 2.Oxygen 3.Fluorine 4.Potassium 5.Phosphorous I forget… how can I tell how many valence electrons are in a group?
Oxidation Numbers Just a fancy name for the charge---- It’s the number of valence electrons an atom wants to give up--- or receive to achieve a nobel gas configuration
Write these somewhere!!!!
Sodium Chloride Draw the Lewis Structure for Sodium Draw the Lewis Structure for Chlorine See how it all fits together?
Magnesium Sulfide Draw the LS for Magnesium How many electrons can it give up? Draw the LS for Sulfur How many empty spots does it have? Does it make sense that these two will fit together?
Twins- Kinky!! Draw the LS for Calcium How many chlorine atoms are needed?
Triplets?? Draw LS for Nitrogen How many Sodium atoms are needed to “complete” nitrogen Name the ionic compound!
Warm Up a.Draw the Lewis Structures for calcium and bromine. b.Identify the type of atom (metal or nonmetal). c.Draw arrows to show the movement of electrons.
We can always tell how many atoms of each element will form a neutral compound… Criss Cross method Work on the Ionic Bonding WS
Naming ionic compounds Name the cation (metal)… …. then the anion (nonmetal) and add “ide” CaCl 2 Let’s practice a few on the IB WS
Important Vocab Terms Electrostatic force - the force that occurs when a + charge is attracted to a - charge (causes the bonds!) Salt- another name for ionic compounds Formula unit- One molecule of an ionic compound
Ionic Compounds Electrostatic attraction between formula units create a stable structure “Crystal Lattice”- formula units, which repeat in a geometric pattern. NaCl
Properties of Ionic Compounds 1. Crystalline solids at room temperature 2. Have very high melting and boiling points 3. Conduct electricity when in a molten state (or dissolved in water)
Warm Up: How many atoms of each element in the following compounds?? NaCl CaCl 2 Na 3 PO 4 Ca(NO 3 ) 2 Al 2 (SO 4 ) 3 Now you practice!!
How do I calculate Molar Mass? 1.Determine the number of atoms of each element. 2.Multiply by the atomic mass. 3.Add’m Up
Ionic Bonding Cut and Paste Activity 1. Color the cations one color and the anions another. 2. Build the neutral compounds. 3.Remember your + charges need to equal the - charges. 4.Name the compounds!
Ionic Bonding with Polyatomic Ions Polyatomic Ions- A group of covalently bonded atoms that have a charge. The charge is attracted to the charge on a metal to form an ionic bond. Polyatomic Ion Rap
What about the Transition Metals? We need to be a little careful with these because Transition Metals often have more than one oxidation number.