PP_15a_chp_2_8_naming_ionic_compounds.ppt
- 1. Section 2.8 Naming Simple Compounds Return to TOC 2/2/2024 Chemistry 1 Vocabulary - Review Q: What is a cation? A: A positive ion formed by a metal Examples: Na+ Ca 2+ Al 3+ Q: What is an anion? A: A negative ion formed by a nonmetal. Examples: H- F- O 2- P 3- Q: What is a polyatomic ion? A: A group of charged atoms NH4 + SO4 2- 1
- 2. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Attraction between + ions and - ions Electrons go from metals to nonmetals electron transfer metal nonmetal ion+ ion– Electrons lost = Electrons gain NOTE: the net charge on the compound is zero 2
- 3. Section 2.8 Naming Simple Compounds Return to TOC 3 Formation of Ionic Compounds
- 4. Section 2.8 Naming Simple Compounds Return to TOC Ionic Bonding What happens when an atom of sodium reacts with an atom of chlorine? Na Na+ + 1e- Cl + 1e- Cl- Na + Cl + 1e- Na+Cl- + 1e- 4
- 5. Section 2.8 Naming Simple Compounds Return to TOC Ionic Bonding We write Na+Cl- as simply NaCl • The ionic compound is neutral – this means the net (overall) charge is = 0. • Now let’s try for cesium reacting with sulfur. 5
- 6. Section 2.8 Naming Simple Compounds Return to TOC Ionic Bonding Cs Cs+ + 1e- S + 2e- S2- Cs + S + 2e- Cs+S2- + 1e- This equation is not balanced. What must be done to correct this? Solution: 1. Write the symbol for each ion present 2.Make sure you include the charge of each ion 6
- 7. Section 2.8 Naming Simple Compounds Return to TOC Writing a Formula Write the formula for the ionic compound that will form between Ba2+ and Cl. Solution: 1. Balance charge with + and – ions 2. Write the positive ion of metal first, and the negative ion Ba2+ Cl 3. Write the number of ions needed as subscripts BaCl2 (NOTE WE CRISSCROSSED THE CHARGES) 7
- 8. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds--Example: Sodium and oxygen react 1. You have to balance the charges. 2. You do this by criss-crossing the value of the charge (not the + or -) Sodium oxide Na+ O2- Na2O we do not write the 1 as a subscript 8
- 9. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Lithium iodide Li+ I – LiI 9
- 10. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Magnesium oxide Mg2+ O2- Mg2O2 MUST be reduced to MgO 10
- 11. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Let’s try a few: Barium nitride Ba3N2 Aluminum oxide Al2O3 Cesium iodide CsI Sodium fluoride NaF Strontium bromide SrBr2 11
- 12. Section 2.8 Naming Simple Compounds Return to TOC Learning Check Write the correct formula for the compounds containing the following ions: A. Na+, S2- B. Al3+, Cl- C. Mg2+, N3- 12
- 13. Section 2.8 Naming Simple Compounds Return to TOC Solution A. Na+, S2- Na2S B. Al3+, Cl- AlCl3 C. Mg2+, N3- Mg3N2 13
- 14. Section 2.8 Naming Simple Compounds Return to TOC 14 • Binary Compounds Composed of two elements Ionic and covalent compounds included • Binary Ionic Compounds Metal—nonmetal • Binary Covalent Compounds Nonmetal—nonmetal Naming Compounds
- 15. Section 2.8 Naming Simple Compounds Return to TOC 15 • Binary Compounds Composed of two elements • Binary Ionic Compounds Metal—nonmetal • Binary Covalent Compounds Nonmetal—nonmetal
- 16. Section 2.8 Naming Simple Compounds Return to TOC 16 • Binary ionic compounds contain positive cations and negative anions. Type I compounds • Metal present forms only one cation. Type II compounds • Metal present can form 2 or more cations with different charges.
- 17. Section 2.8 Naming Simple Compounds Return to TOC 17 1. Contain 2 different elements 2. The cation is always named first and the anion second. 2. A cation has same name as element. Examples: Ca2+ calcium Al3+ aluminum Na + sodium 3. A anion has the same name as the element name with adding –ide to the end. Examples: Cl - chloride S2- sulfide P3- phosphide Binary Ionic Compounds (Type I monatomic cations & anions)
- 18. Section 2.8 Naming Simple Compounds Return to TOC 18 Common Simple Cations and Anions
- 19. Section 2.8 Naming Simple Compounds Return to TOC 19 1. The cation is always named first and the anion second. 2. A simple cation takes its name from the name of the element. 3. A simple anion is named by taking the first part of the element name (the root) and adding –ide. Rules for Naming Type I Ionic Compounds
- 20. Section 2.8 Naming Simple Compounds Return to TOC 20 • Examples: KCl Potassium chloride MgBr2 Magnesium bromide CaO Calcium oxide Binary Ionic Compounds (Type I)
- 21. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds Now let us put it all together: Na3N Cation: sodium Anion: nitride Compound: Sodium nitride 21
- 22. Section 2.8 Naming Simple Compounds Return to TOC Ionic Compounds BaO Cation: barium Anion: oxide Compound: barium oxide 22
- 23. Section 2.8 Naming Simple Compounds Return to TOC Naming Binary Ionic Compounds (Type I) SUMMARY - Name the metal first, then the nonmetal with ending changed to -ide. Examples: NaCl sodium chloride ZnI2 zinc iodide Al2O3 aluminum oxide KCl Potassium chloride MgBr2 Magnesium bromide CaO Calcium oxide 23
- 24. Section 2.8 Naming Simple Compounds Return to TOC 24 Exercise What is the name of the compound SrBr2? a) strontium bromine b) sulfur bromide c) strontium dibromide d) strontium bromide
- 25. Section 2.8 Naming Simple Compounds Return to TOC Learning Check Complete the names of the following type I binary compounds: Na3N sodium ________________ KBr potassium________________ Al2O3 aluminum ________________ MgS _________________________ 25
- 26. Section 2.8 Naming Simple Compounds Return to TOC Solution Complete the names of the following binary compounds: Na3N sodium nitride KBr potassium bromide Al2O3 aluminum oxide MgS magnesium sulfide 26
- 27. Section 2.8 Naming Simple Compounds Return to TOC 27 Binary Ionic Compounds (Type II) • Metals in these compounds can form more than one type of positive charge. • Charge on the metal ion must be specified. • Roman numeral indicates the charge of the metal cation. • Transition metal cations usually require a Roman numeral.
- 28. Section 2.8 Naming Simple Compounds Return to TOC 28 • Metals in these compounds form more than one type of positive charge. • Charge on the metal ion must be specified. • Roman numeral indicates the charge of the metal cation. • Transition metal cations that form 2 or more positive ions require a Roman numeral. Binary Ionic Compounds (Type II) 1+ or 2+ ____________________ 2+ or 3+ Cu+, Cu2+ Fe2+, Fe3+ copper(I) ion iron(II) ion copper (II) ion iron(III) ion
- 29. Section 2.8 Naming Simple Compounds Return to TOC 29 Common Type II Cations
- 30. Section 2.8 Naming Simple Compounds Return to TOC 30 1. The cation is always named first and the anion second. 2. Because the cation can assume more than one charge, the charge is specified by a Roman numeral in parentheses. Rules for Naming Type II Ionic Compounds
- 31. Section 2.8 Naming Simple Compounds Return to TOC 31 • Examples: CuBr Copper(I) bromide FeS Iron(II) sulfide PbO2 Lead(IV) oxide Binary Ionic Compounds (Type II)
- 32. Section 2.8 Naming Simple Compounds Return to TOC Binary Ionic Compounds (Type II) Use a roman number after the name of a metal that forms two or more ions (note compound is neutral) Example: FeCl3 (Fe3+) iron (III) chloride CuCl (Cu+ ) copper (I) chloride SnF4 (Sn4+) tin (IV) fluoride PbCl2 (Pb2+) lead (II) chloride Fe2S3 (Fe3+) iron (III) sulfide 32
- 33. Section 2.8 Naming Simple Compounds Return to TOC 33 Exercise What is the name of the compound CrO2? a) chromium oxide b) chromium(II) oxide c) chromium(IV) oxide d) chromium dioxide
- 34. Section 2.8 Naming Simple Compounds Return to TOC 34 Exercise What is the correct name of the compound that results from the most stable ion for sulfur and the metal ion that contains 24 electrons? a) iron(III) sulfide b) chromium(II) sulfide c) nickel(III) sulfate d) iron(II) sulfide
- 35. Section 2.8 Naming Simple Compounds Return to TOC Learning Check Complete the names of the following binary compounds with variable metal ions: FeBr2 iron (_____) bromide Cu2O copper (_____) oxide SnCl4 ___(_____ ) ______________ Fe2O3 ________________________ CuS ________________________ 35
- 36. Section 2.8 Naming Simple Compounds Return to TOC Solution Complete the names of the following binary compounds with variable metal ions: FeBr2 iron ( II ) bromide Cu2O copper ( I ) oxide SnCl4 tin (IV) chloride Fe2O3 iron (III) oxide CuS copper (II) sulfide 36
- 37. Section 2.8 Naming Simple Compounds Return to TOC Learning Check Name the following compounds: A. CaO B. SnCl4 C. Co2O3 37
- 38. Section 2.8 Naming Simple Compounds Return to TOC Solution Name the following compounds: A. CaO calcium oxide B. SnCl4 tin(IV) chloride C. Co2O3 cobalt (III) oxide 38
- 39. Section 2.8 Naming Simple Compounds Return to TOC 39 • Polyatomic ions are charged entities composed of several atoms bound together. • They have special names and must be memorized. (see Table 2.5 on pg. 62 in text). • Examples of compounds containing polyatomic ions: NaOH Sodium hydroxide Mg(NO 3 ) 2 Magnesium nitrate (NH 4 ) 2 SO 4 Ammonium sulfate
- 40. Section 2.8 Naming Simple Compounds Return to TOC 40 Names of Common Polyatomic Ions
- 41. Section 2.8 Naming Simple Compounds Return to TOC 41 • Naming ionic compounds containing polyatomic ions follows rules similar to those for binary compounds. Ammonium acetate
- 42. Section 2.8 Naming Simple Compounds Return to TOC 42 NaOH Sodium hydroxide Mg(NO3)2 Magnesium nitrate (NH4)2SO4 Ammonium sulfate FePO4 Iron(III) phosphate Examples
- 43. Section 2.8 Naming Simple Compounds Return to TOC 43 Exercise What is the name of the compound KClO3? a) potassium chlorite b) potassium chlorate c) potassium perchlorate d) potassium carbonate