Oxyanions Naming Polyatomic Ions and Oxyanions Acids Oxyanions- negative ions containing Oxyanions may contain the prefix oxygen. “hypo-”, less than, or “per-”, more than. These have the suffix “-ate” or “-ite” For example - “-ate” means it has more oxygen atoms ClO4 Perchlorate bonded, “-ite” has less - ClO3 Chlorate For example - ClO2 Chlorite 2- SO4 sulfate ClO- Hypochlorite 2- SO3 sulfite
Acids Naming acids Naming Acids Certain compounds produce H+ ions in Does it contain oxygen? water, these are called acids. If it does not, it gets the prefix “hydro-” and If it does contain an oxyanion, then the suffix “-ic acid” replace the ending. You can recognize them because the neutral compound starts with “H”. HCl If the ending was “–ate”, add “-ic acid” Hydrochloric acid If the ending was “–ite”, add “-ous acid” For example HCl, H2SO4, and HNO3. HF Don’t confuse a polyatomic ion with a H2SO4 Sulfuric Acid Hydrofluoric acid neutral compound. H2SO3 Sulfurous Acid HCN HCO - is hydrogen carbonate, not an acid. 3 Hydrocyanic acid
Examples Examples Nomenclature (naming) of Covalent compounds HNO3 HNO3 Nitric Acid HI HI Hydroiodic acid
H3AsO4 H3AsO4 Arsenic Acid
HClO2 HClO2 Chlorous Acid
1 Determining the type of bond Covalent bonding is very Covalent bonding is very First, determine if you have an ionic different from ionic naming compound or a covalent compound. similar to ionic naming A metal and a nonmetal will form an You always name the one that is least Ionic names ignored the subscript ionic bond. electronegative first (furthest from because there was only one possible Compounds with Polyatomic ions form fluorine) ratio of elements. ionic bonds. Most electronegative last, and gets the Covalent gives several possibilities so Nonmetals bonding together or suffix “-ide”. we have to indicate how many of each Nonmetals and a metalloid form atom is present in the name covalent bonds.
Prefixes you have to know Examples Examples prefix meaning prefix meaning CO CO carbon monoxide *mono- 1 hex- 6 CO CO di- 2 hept- 7 2 2 carbon dioxide tri- 3 oct- 8 NI3 NI3 tetr- 4 non- 9 nitrogen triiodide
pent- 5 dec- 10 P4O6 P4O6 * the first atom named does not get the prefix tetraphosphorus hexoxide “mono-”, it just keeps its original name!
Continuing Continuing Something to be wary of Many chemicals have “common names” I4O9 I4O9 tetriodine nonoxide because they have been in use for so long S2F10 S2F10 like H O disulfur decafluoride 2 2 following naming rules it is… IF7 IF7 dihydrogen dioxide Iodine heptafluoride commonly it is hydrogen peroxide. Si2Cl6 Si2Cl6 disilicon hexachloride
2 Homework
HW -go to http://www.DHMO.org and write a 2 paragraph reaction to the site citing actual information presented in the site. Not just an angry rant, but an intelligent opinion. Pay attention to what you just learned!
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