2.2 Naming Ionic & Covalent Compounds.pptx

science

1. 2.2 Writing Names and Formulas of Ionic Compounds Learning Goals … write the name of ionic compounds (binary, polyatomic or multivalent) write the formula for ionic compounds (binary, polyatomic, multivalent) Gizmo - Ionic Bonds

2. Imagine a conversation at the dinner table went something like this… “Please pass the sodium chloride” “Do you have enough sucrose for your tea?” “May I please have some more dihydrogen monoxide?” “These biscuits are so hard and flat! I must have forgotten to put the sodium hydrogen carbonate in the dough!”

3. Naming so far… Ionic bonds are named by removing the last few letters of the non-metals and adding “ -ide ” Covalent bonds use “-ide” but also use prefixes to indicate the number of atoms. Classical and Stock system for Multivalent ions

4. 1. Binary Ionic Compounds eg ) potassium nitride magnesium fluoride calcium sulfide Na 2 O metal + non-metal ( EN > 1.7) end in – ide criss cross charges K + N -3 K 3 N Mg +2 F - MgF 2 CaS Ca +2 S -2 Sodium oxide Ca 2 S 2

5. Common Polyatomic Ions Nick  nitrate  NO 3 - The Camel  Carbonate  CO 3 2- Ate Clam  Chlorate  ClO 3 - Supper  Sulfate  SO 4 2- In Phoenix  Phosphate  PO 4 2-

6. 2. Polyatomic Compounds metal + polyatomic ion usually ends in –ate or – ite criss cross charges eg ) sodium chlorate beryllium phosphate MgSO 4 Na + ClO 3 - NaClO 3 Be +2 PO 4 -3 Be 3 (PO 4 ) 2 Magnesium sulfate

7. Acidic Salts When polyatomic ions with a charge >1 are bound to metal AND a hydrogen Eg HCO 3 - and Na + Sodium hydrogen Carbonate (bicarbonate) Try: K 2 HPO 4 Mg(HSO 3 ) 2

8. Stock System Developed by Prussian scientist Alfred Stock Morveau system was flawed because it was limited to 2 charges Roman numerals represent the charge of multivalent electrons

9. 3. Multivalent Metals Contains a metal with more than one possible charge (most common valence is listed first on periodic table) Roman numerals indicate charge eg ) gold (I) chloride gold (III) chloride SnCl 2 SnCl 4 Pb (SO 4 ) 2 FeS Au + Cl - AuCl Au +3 Cl - AuCl 3 tin (II) chloride tin (IV) chloride Lead (IV) sulfate Iron (II) sulfide

10. Latin names (Classical system) -IC = Larger Charge - OUS = Smaller Charge Element (Valence) English Name Latin Name Higher Valence Lower Valence Cu (1+, 2+) Copper Cuprum Cupric Cuprous Fe (2+, 3+) Iron Ferrum Ferric Ferrous Pb (2+, 4+) Lead Plumbum Plumbic Plumbous Sn (2+, 4+) Tin Stannum Stannic Stannous

11. 2.2 Writing Names and Formulas of Covalent Compounds Learning Goals … … write the name and formula for covalent compounds … write the name and formula for hydrates … write the name and formula for acids Gizmo - Covalent Bonds

12. 4. Covalent Compounds 2 or more non-metals ends in –ide do not criss-cross charges use prefixes: Mono [1], di [2], tri [3], tetra[4], penta [5], hexa [6], hepta [7], octa [8], nona [9], deca [10] you do not need to put mono - for the 1 st element but you do for the 2 nd element

13. Covalent Compound Examples A rsenic tri brom ide Phosphorus penta fluor ide Di chlorine mon ox ide AsBr 3 PF 5 Cl 2 O CF 4 Carbon tetra fluor ide Di nitrogen tri chlor ide N 2 Cl 3 Be sure to remove the “a” if following the prefix is “- ao -” Ex. Pent ao xide becomes pent o xide

14. 5. Gases Fluorine gas F 2 (diatomic element) Argon gas Ar (noble gases are not diatomic) Note : diatomic elements ( H ave N o F ear O f I ce C old B eers ) HOFBrINCl Hint : they end in –gen or – ine

15. 6. Hydrates An ionic compound surrounded in a cage of water molecules Water molecules help make up the lattice structure Evaporates with heat to pure, distilled water The prefix indicating the number of water molecules is added to ‘hydrate’ to name these

16. 6. Hydrates Copper (II) sulfate pentahydrate CuSO 4 • 5H 2 O Na 2 CO 3 • 6H 2 O Sodium carbonate hexahydrate SnCl 4 • 5H 2 O Tin(IV) chloride pentahydrate Iron (III) nitrate nonahydrate Fe( NO 3 ) 3 • 9 H 2 O

17. 7. Naming Acids There are 2 types of acids: Binary acids : composed of Hydrogen first a nd one other element (usually a halogen) Oxyacids (Ternary Acids) : composed of H and a polyatomic ion

18. Binary acids Hydro _________________ ic acid Ex) HCl HF H 2 S Hydrobromic acid Hydrophosphoric acid hydro chlor ic acid hydro fluor ic acid hydro sulfur ic acid HBr H 3 P

19. 1. Polyatomic ions that end in -ate , acid ends in - ic HClO 3 ion is chlor ate ( ClO 3 - ) chlor ic acid * H 2 SO 4 ion is sulf ate ( SO 4 2 - ) sulf uric acid HClO 4 ion is perchlor ate ( ClO 4 - ) perchlor ic acid *Sulfuric Acid, Phosphoric Acid Oxyacids (Ternary acids)

20. 2. For polyatomic ions that end in - ite , acid ends in – ous HNO 2 ion is nitr ite ( NO 2 - ) nitr ous acid HClO ion is hypo chlor ite ( ClO - ) hypo chlor ous acid Oxyacids (Ternary acids)

21. What was the original ending? Nitrate ( NO 3 - ) Sulfate ( SO 4 2 - ) Sulfite ( SO 3 2 - ) Perchlorate ( ClO 4 - ) Chlorate ( ClO 3 - ) Chlorite ( ClO 2 - ) Hypochlorite( ClO - )

22. Can I … write the name and formula for covalent compounds write the name and formula for hydrates write the name and formula for acids write the name of ionic compounds (binary ,polyatomic or multivalent) write the formula for ionic compounds (binary, polyatomic, multivalent) Classwork: Worksheets Tomorrow: Work Period / Take-Up