2.  As the name might suggest (BInary), these compounds contain exactly two elements.  In this class both of these elements will be non-metals.  If a compound is made of exactly two elements and both of them are non-metallic you will use the skills you learn today to name the compound.

3.  Names of binary molecular compounds are NOT to be memorized. They must be figured out. ◦ NO 2 is called nitrogen dioxide. ◦ P 2 O 5 is called diphosphorous pentoxide. ◦ SO 3 is called sulfur trioxide.  Today I will teach you how to name these compounds.  NOTE: All are made up of exactly two non- metallic elements.

4.  Look right. You will want to copy this chart down.  These prefix indicate the number of each atom present in a compound.  Rule 1: If the first element has only one atom it receives no prefix. Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

5.  Rule 2: The second atom ALWAYS gets a prefix, even if there’s only one.  CO is called carbon monoxide.  Rule 3: The second atom ALWAYS ends in “ide”. Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

6.  Here’s an example problem: ◦ Name: Sulfur hexafluoride ◦ Symbol SF 6 Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

7.  Here’s another example problem: ◦ Name: Tetraphosphorous decoxide ◦ Symbol P 4 O 10 Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

8.  Here, you try one ◦ Name: Carbon tetrafluoride ◦ Symbol ????? Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

9.  Here, you try one ◦ Name: Carbon tetrafluoride ◦ Symbol CF 4 Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

10.  Try another one: ◦ Name: ??? ◦ Symbol PCl 5 Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

11.  Try another one: ◦ Name: Phosphorus pentachloride ◦ Symbol PCl 5 Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

12.  One last one: ◦ Name: ?????? ◦ Symbol N 2 O Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

13.  One last one: ◦ Name: Dinitrogen monoxide Both have prefixes!!! ◦ Symbol N 2 O Number of atoms Prefix 1mono 2di 3tri 4tetra 5pent 6hex 7hept 8oct 9non 10dec

14.  That’s it, there is no more.  All you need to do now is practice. Use the two files below this PowerPoint to work on converting between name and symbol, symbol and name. Once you’ve mastered this skill move right on to naming hydrocarbons.