2. Naming Chemicals AP Chemistry

3. Classes of Chemicals Elements Elements Ionic Compounds Ionic Compounds Covalent Compounds Covalent Compounds Organic Compounds Organic Compounds

4. Elements All elements on the periodic table All elements on the periodic table All just one word: iron, sodium, neon, etc. All just one word: iron, sodium, neon, etc. All neutrally charged All neutrally charged Mostly monatomic: Fe, Na, Ne Mostly monatomic: Fe, Na, Ne Some diatomic: H 2 O 2 N 2 Cl 2 Br 2 I 2 F 2 Some diatomic: H 2 O 2 N 2 Cl 2 Br 2 I 2 F 2 Some polyatomic: S 8, P 4 Some polyatomic: S 8, P 4 Gold

5. Ionic Compounds Made of one metal positive ion (cation) and one non-metal negative ion (anion) Made of one metal positive ion (cation) and one non-metal negative ion (anion) Always two words starting with the cation and ending with the anion Always two words starting with the cation and ending with the anion Cation is same name as element Cation is same name as element Anion always has a different suffix Anion always has a different suffix Sodium chloride

6. Anion Suffixes Monatomic atoms end with –ide Monatomic atoms end with –ide Oxygen atom = O Oxygen atom = O Oxide ion = O -2 Oxide ion = O -2 Sulfur atom = S Sulfur atom = S Sulfide ion = S -2 Sulfide ion = S -2 Chlorine atom = Cl Chlorine atom = Cl Chloride ion = Cl -1 Chloride ion = Cl -1

7. Oxy-Anions Oxy- anions end in –ate Oxy- anions end in –ate Sulfate = SO 4 -2 Chlorate = ClO 3 -1 Sulfate = SO 4 -2 Chlorate = ClO 3 -1 Chromate = CrO 4 -2 Nitrate = NO 3 -1 Chromate = CrO 4 -2 Nitrate = NO 3 -1 If the anion is further oxidized then add the prefix per- If the anion is further oxidized then add the prefix per- ClO 3 -1 = chlorate ClO 4 -1 = perchlorate ClO 3 -1 = chlorate ClO 4 -1 = perchlorate

8. Less Oxidation If the anion is less oxidized by 1 then change the –ate suffix to an –ite suffix If the anion is less oxidized by 1 then change the –ate suffix to an –ite suffix SO 4 -2 = sulfateSO 3 -2 = sulfite SO 4 -2 = sulfateSO 3 -2 = sulfite ClO 3 -1 = chlorateClO 2 -1 = chlorite ClO 3 -1 = chlorateClO 2 -1 = chlorite If the anion is less oxidized again then add the prefix hypo- If the anion is less oxidized again then add the prefix hypo- ClO -1 = hypochloriteSO 2 -2 = hyposulfite ClO -1 = hypochloriteSO 2 -2 = hyposulfite

9. Summary Per- -ate -ate-ite Hypo- -ite Chlor- ClO 4 -1 Perchlorate ClO 3 -1 chlorate ClO 2 -1 chlorite ClO -1 hypochlorite Sulf- SO 4 -2 sulfate SO 3 -2 Sulfite SO 2 -2 Hyposulfite Nitr- NO 3 -1 Nitrate NO 2 -1 Nitrite Phos- PO 4 -3 Phosphate PO 3 -3 Phosphite

10. Sulfur Replacement If one of the oxygens in an oxy-anion is replaced with a sulfur then add the prefix thio- If one of the oxygens in an oxy-anion is replaced with a sulfur then add the prefix thio- SO 4 -2 = sulfateS 2 O 3 -2 = thiosulfate SO 4 -2 = sulfateS 2 O 3 -2 = thiosulfate SO 3 -2 = sulfiteS 2 O 2 -2 = thiosulfite SO 3 -2 = sulfiteS 2 O 2 -2 = thiosulfite CNO -1 = cyanateCNS -1 = thiocyanate CNO -1 = cyanateCNS -1 = thiocyanate

11. Anion Summary Mon-atomic anions end in –ide Mon-atomic anions end in –ide Oxy-anions end in –ate or –ite Oxy-anions end in –ate or –ite Add prefixes per- and hypo- when necessary Add prefixes per- and hypo- when necessary Add thio- prefix when a sulfur replaces and oxygen Add thio- prefix when a sulfur replaces and oxygen

12. Combining Ions Ionic compounds are always neutrally charged so the number of each ion within the compound is fixed Sodium oxide: Na +1 O -2 Since the compound must be neutral we need another positive charge Na +1 Now we have two sodium atoms to balance out the oxide so the final formula is: Na 2 O

13. Parenthesis Use parenthesis for multiple polyatomic ions Use parenthesis for multiple polyatomic ions Aluminum chromate Al +3 CrO 4 -2 Al 2 (CrO 4 ) 3

14. Be careful of Hydroxides! Calcium hydroxide Ca +2 OH -1 Ca(OH) 2 CaOH 2

15. Transition Metals

16. Transition Metals often have more than one charge Transition Metals often have more than one charge Examples: Fe +2 and Fe +3 Examples: Fe +2 and Fe +3 This makes a difference in formulae: This makes a difference in formulae: Iron chloride could be: Iron chloride could be: FeCl 2 or FeCl 3 FeCl 2 or FeCl 3

17. So what do we do? Since FeCl 2 and FeCl 3 are obviously not the same compound, they can’t both have the same name. Since FeCl 2 and FeCl 3 are obviously not the same compound, they can’t both have the same name. We differentiate them by using a Roman Numeral to indicate the charge on the transition metal We differentiate them by using a Roman Numeral to indicate the charge on the transition metal Fe +2 and Cl -1  FeCl 2 = iron (II) chloride Fe +2 and Cl -1  FeCl 2 = iron (II) chloride Fe +3 and Cl -1  FeCl 3 = iron (III) chloride Fe +3 and Cl -1  FeCl 3 = iron (III) chloride Be sure to note that the roman numeral indicates charge and not number. Be sure to note that the roman numeral indicates charge and not number.

18. Quick practice Sodium bromide Sodium bromide NaBr Calcium oxideCaO Aluminum nitrateAl(NO 3 ) 3 Ammonium phosphate(NH 4 ) 3 PO 4 Barium hydroxideBa(OH) 2 Copper (I) sulfideCu 2 S Copper (II) sulfateCuSO 4 Iron (III) dichromateFe 2 (Cr 2 O 7 ) 3

19. More practice Potassium hypochlorite Potassium hypochlorite KClO Sodium sulfiteNa 2 SO 3 Aluminum bromateAl(BrO 3 ) 3 Ammonium phosphite(NH 4 ) 3 PO 3 Magnesium nitriteMg(NO 2 ) 2 Iron (III) perchlorateFe(ClO 4 ) 3 Strontium cyanateSr(CNO) 2 Copper (I) thiosulfateCu 2 S 2 O 3

20. Covalent Compounds Comprised of two or more non-metals covalently bonded Comprised of two or more non-metals covalently bonded Start with less electronegative and end with more electronegative Start with less electronegative and end with more electronegative Name as normal except that all compounds change the second element to an –ide ending Name as normal except that all compounds change the second element to an –ide ending

21. Covalent Examples CO = carbon oxide CO = carbon oxide CS 2 = carbon sulfide CS 2 = carbon sulfide NF 3 = nitrogen fluoride NF 3 = nitrogen fluoride Notice in each example the more electronegative atom is second and ends in -ide Notice in each example the more electronegative atom is second and ends in -ide

22. Problem Covalent compounds can combine in multiple proportions- that is there can be more than one ratio of atoms in a compound Covalent compounds can combine in multiple proportions- that is there can be more than one ratio of atoms in a compound COvs. CO 2 COvs. CO 2 They can’t both be carbon oxide They can’t both be carbon oxide NO 2 vs.N 2 O 4 NO 2 vs.N 2 O 4 They can’t both be nitrogen oxide They can’t both be nitrogen oxide

23. Solution? Use prefixes to indicate the number of covalently bonded atoms present in the molecule Use prefixes to indicate the number of covalently bonded atoms present in the molecule COvs.CO 2 COvs.CO 2 Carbon monoxideCarbon dioxide Carbon monoxideCarbon dioxide

24. Prefixes 1 2 3 4 5 6 7 8 9 10 10 Mono- Di- Di- Tri- Tri- Tetra- Tetra- Hexa- Hexa- Penta- Penta- Hepta- Hepta- Octa- Octa- Nona- Nona- Deca- Deca-

25. Overall Covalent Rules Comprised of two or more non-metals covalently bonded Comprised of two or more non-metals covalently bonded Start with less electronegative and end with more electronegative Start with less electronegative and end with more electronegative Name as normal except that all compounds change the second element to an –ide ending Name as normal except that all compounds change the second element to an –ide ending Add a prefix to indicate number of atoms in the compound Add a prefix to indicate number of atoms in the compound The second atom ALWAYS gets a prefix The second atom ALWAYS gets a prefix The first atom can ignore MONO- The first atom can ignore MONO-

26. Practice CO CO Carbon monoxide N 2 O 5 N 2 O 5 Dinitrogen pentoxide Dinitrogen pentoxide PCl 5 PCl 5 Phosphorus pentachloride Phosphorus pentachloride SO 3 SO 3 Sulfur trioxide Sulfur trioxide N 2 O N 2 O Dinitrogen monoxide Dinitrogen monoxide