Types, Naming & Explaining COMPOUNDS

Learning Goals I CAN EXPLAIN THE PROPERTIES OF IONIC & MOLECULAR COMPOUNDS.

BACKGROUND INFORMATION DO NOT COPY DOWN THE FOLLOWING SLIDES

 The millions of types of compounds that have been discovered and described can be categorized as one of two types:  Ionic  Molecular TYPES OF COMPOUNDS

 Composed of at least one metal and one nonmetal.  Most share the following properties:  High melting points  Form crystals, very regular arrangements of particles  Dissolve in water to form solutions that conduct electricity  Solids at room temperature  Example: NaCl (salt) IONIC COMPOUNDS

 The transfer of electrons from the metal to the nonmetal.  Causes metal to form positive ion and nonmetal to form negative ion.  Opposites attract and they arrange themselves in an alternating pattern called a crystal arrangement. HOW DO IONIC COMPOUNDS FORM?

IONIC COMPOUNDS

 When two or more non-metals combine together.  Atoms SHARE electrons to obtain stability.  Example: Sugar (C 12 H 22 O 11 )  Share the following properties:  Can be solids, liquids or gases  Usually good insulators but poor conductors  Have relatively low boiling points MOLECULAR COMPOUNDS

NAMING COMPOUNDS

Step #1 Step #2 Step #3 Naming Step #1 Step #4 Naming Step #1 Step #3 Naming Step #1 Step #4 Naming Step #2 Yes No Step #5 Naming Step #3

Is the first element a metal? QUESTION

 It’s made up of a metal and a non-metal.  Example: CaCl 2 Name: __________ _________ IT’S AN IONIC COMPOUND

 Write down the name of the element that is the METAL (the first element in the formula)  Example: CaCl 2 Name: Calcium _________ NAMING STEP #1

 Name the non-metal element second. The ending of its name changes to “ide”  Example: CaCl 2 Name: Calcium Chloride NAMING STEP #2

 It’s made up of two non-metals  Example: N 2 O 5 Name: __ ________ __ _______ IT’S AN MOLECULAR COMPOUND

 Write down the name of the first element.  Example: N 2 O 5 Name: __nitrogen __ _______ NAMING STEP #1

 Name the second element. The ending of its name changes to “ide”  Example: N 2 O 5 Name: __nitrogen __oxide NAMING STEP #2

 Add prefixes indicating the number of atoms of each element.  Example: N 2 O 5 Name: dinitrogen pentaoxide NAMING STEP #3 Prefixes You Need to Know: Mono = 1 Di = 2 Tri = 3 Tetra = 4 Penta = 5 Hexa = 6 Hepta = 7 Octa = 8

NOW THE FORMULAS!!

The Question Molecular Compound Step #1 Molecular Compound Step #2 Yes No Ionic Compound Step #1 Ionic Compound Step #3a Ionic Compound Step #2a Ionic Compound Step #2b Ionic Compound Step #3b

Is the first element a metal? QUESTION

 Identify the ions and their charges.  Example: aluminum oxide  Rough work: Al O IONIC COMPOUNDS STEP #1

IONIC COMPOUNDS STEP #2A  Picture the charges sitting on a teeter-totter. How many of each atom would you need to balance out each side?  Example: aluminum oxide  Rough work: Al O Al 3+ O 2- Total = 2 atoms 3 atoms

IONIC COMPOUNDS #3A  Write the final of ratio of atoms in the element.  Example: aluminum oxide  Answer: Al 2 O 3 Al 3+ O 2- Total = 2 atoms 3 atoms

 Write the symbols for each of the elements in the compound.  Example: nitrogen trifluoride Formula: N F MOLECULAR COMPOUND CHEMICAL FORMULAS: PART #1

 Write the subscript to indicate the number of atoms based on the prefix. Do not write the number 1.  Example: nitrogen trifluoride Formula: NF 3 MOLECULAR COMPOUND CHEMICAL FORMULAS: PART #2 Prefixes You Need to Know: Mono = 1 Di = 2 Tri = 3 Tetra = 4 Penta = 5 Hexa = 6 Hepta = 7 Octa = 8