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Chemical Nomenclature Naming compounds and writing chemical formulas. Understanding Nomenclature. Nomenclature refers to the process of naming chemicals. Initially the focus is on the most basic rules and ideas involved in the naming of compounds. I. Binary Compounds
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Chemical NomenclatureNaming compounds and writing chemical formulas.
Understanding Nomenclature Nomenclature refers to the process of naming chemicals. Initially the focus is on the most basic rules and ideas involved in the naming of compounds.
I. Binary Compounds A binary compound contains just two element 1. The element with the positive charge ( more metallic ), is written first. 2. The element with the negative charge( more non-metallic) is written second
Understanding Nomenclature The first word (metal or positive ion) remains the same word • The second word(negative ion) is formed by changing the ending of the element name to “ide”. • For example: fluorine changes to fluoride, and oxygen to oxide sodium chloride ex: NaCl potassium bromide KBr
Predicting Charges on Monatomic Ions +1 +2 +3 +4 +5 +2 +4 -4 -3 -2 -1 0
Cations Anions Formula Name Formula Name Charge Charge H+ hydrogen H- hydride Li+ lithium F- fluoride Na+ sodium Cl- chloride K+ potassium Br- bromide Cs+ cesium I- iodide Ag+ silver Mg2+ magnesium O2- oxide Ca2+ calcium S2- sulfide Sr2+ strontium Ba2+ barium Zn2+ zinc Cd2+ cadmium Al3+ aluminum N3- nitride Common Monoatomic Ions +1 -1 Common + ions are in blue. +2 -2 Common - ions are in red. +3 -3
1. Using the rules given , name the compounds listed below. 1. MgO ____________________ 2. CaI2 ______________________ 3. BaS ____________________ 4. ZnI2 ______________________ 5. CaO ____________________ 6. Ag2O_____________________ 7. K3P ____________________ 8. AlBr3_____________________ 9. Na3N ____________________ 10. MgS_____________________
Writing proper Chemical formulas. The net charge of the formula must be zero potassium and chlorine = potassium chloride 1+ 1- = 0 KCl = KCl
Using the rule given , give the formula for these compounds 12. sodium chloride ____________13. potassium iodide __________ 14. magnesium sulfide __________15. aluminum bromide __________ 16. strontium oxide ____________ 17. sodium sulfide __________ 18. rubidium phosphide _________19. barium nitride __________
Crisscross Method simplified method for writing these formulas Calcium and bromide = calcium bromide Ca2+Br1-=0 Ca2+Br1- 2 1 Subscripts Ca2+Br1- 1 2 2+ 2- = 0 Ca1Br2 **But we don’t write ones!!! CaBr2
Crisscross Method simplified method for writing these formulas aluminum and sulfide = aluminum sulfide Al3+S2-=0 Al3+S2- 3 2 Subscripts Al3+S2- 2 3 6+ 6- = 0 Al2S3 Al2S3
Groups/Families VIIIA IA • 23, 24, 23, 23, 23, 12, 2 • 1, 2 • 24, 13, 12 IIA VIIA VA VIA Cr Mn Fe Co Ni Cu Zn Zn Zn +1 +2 -4 -3 -2 -1 0 +2 +3 +2 +4 +2 +3 +2 +3 +2 +3 +1 +2 +2 +2 +4 +3 +5 +3 Ag Cd I-VIIIB +1 +2 multiple charges Au Pt Hg Hg +2 +4 +1 +3 +1 +2
Type II Binary Compounds (Stock System) Some metallic element are capable of more than one positivecharge. We will indicated these with a roman numeral in parenthesis following the name of the positive element. Roman numeral = the + charge iron (II) = 2+ and iron (III) = 3+ ***Used only when:*** MORE THAN 1 POSITIVE CHARGE
Copper Cu+1 copper(I) Cu+2 copper(II) Co+2 cobalt(II) Cobalt Co+3 Fe+2 cobalt (III) iron(II) Iron Fe+3 iron(III) Pb+2 lead(II) Lead Pb+4 lead(IV) Sn+2 tin(II) Tin Sn+4 tin(IV) Metals With Several Oxidation States Table 2.4 (partial) Element Ion Formula Stock Name Old School
Type II Binary Compounds (Stock System) Compare FeCl2 & FeCl3 iron and chloride = iron chloride (II) 2+ 2- = 0 FeCl 1- 2 1 iron chloride (III) iron chloride FeCl1- 3 3+ 3- = 0 ***Used only when:*** MORE THAN 1 POSITIVE CHARGE
Type II Binary Compounds 4. Name the following compounds. 21. CuO ______________________ 22. PbS ________________________ 23. HgCl ______________________ 24. MnO2 _________________________ 25. Fe2S3 ______________________ 26. SnBr2 ________________________ 27. BiCl3 ______________________ 28. PbCl4 ________________________
Old School The "ous"-"ic" System Another method of indicating metallic ions with more than one charge is: a suffix The suffix -ous is used for the lower charge. while the suffix -icis used for thehigher ionic charge
Copper Cu+1 copper(I) cuprous Cu+2 copper(II) cupric Co+2 cobalt(II) Cobalt Co+3 Fe+2 cobalt (III) iron(II) ferrous Iron Fe+3 iron(III) ferric Pb+2 lead(II) Lead Pb+4 lead(IV Sn+2 tin(II) stannous cobaltous plumbous Tin Sn+4 tin(IV) plumbic stannic cobaltic Metals With Several Oxidation States Table (partial) Element Ion Formula Stock Name Old School
Old School The "ous"-"ic" System (old school)(stock)formula 29. ferric chloride ________________________ _____________ 30. stannic oxide ________________________ _____________ 31. mercuric iodide ________________________ _____________ 32. cuprous oxide ________________________ _____________ 33. plumbous sulfide ________________________ _____________ 34. antimonic bromide _______________________ ____________ 35. aurous phosphide ________________________ _____________
* Chemistry trivia time: In the James Bond movie Goldfinger who was the villian? Auric Goldfinger What was the license plate number on Goldfinger's Rolls Royce? AU3 What was the name of Goldfinger's business establishment? Auric Enterprises ** Mercury's name was changed because hydroargentous and hydroargentic would be just to much to handle
Ternary Compounds It takes “3” or more A ternary compound contains three or more different elements. Ternary compounds usually contain one or morepolyatomic ions ( radicals ). Examples: Fe(ClO4)2 ; NaOH : NH4MnO4 When writing the formula – the basic rules apply. Polyatomic ions ( radicals )are treated just like an ion.
Determining Names and Formulas of Ionic Compounds Containing Polyatomic Ions Ex: Calcium hydroxide Calcium and hydroxide = calcium hydroxide Ca2+OH1-=0 Ca2+OH1- CaOH2 2 1 Subscripts But OH2 = H2O = water !!! ***Parentheses : need to be used whenever more than a single polyatomic ion is needed to balance the charges - in other words if you add a subscript put the polyatomic radical in parentheses. ( ) Ca OH 2
CO3-2 carbonate CrO4-2 chromate OH- hydroxide Cr2O7-2 dichromate chlorate ClO3- O2-2 peroxide NO2- nitrite SO4-2 sulfate PO4-3 NO3- nitrate phosphate MnO4- permanganate Some Common Polyatomic Ions ( Radicals) Formula Formula Name Name Cations ammonium NH4+ Common Anions acetate CH3COO- CN- cyanide
... the `ate Polyatomic Ions – they all contain oxygen -1 -2 -3 O4 O3 O3 O3 O4 O3 O4
... the `ate Polyatomic Ions – they all contain oxygen -1 -2 -3 MnO3- CO32- PO43- ClO3- CrO42- SO42- NO3-
... the `ate Polyatomic Ions Oxgen -1 -2 -3 Manana ? Please Chemistry Class Crazy Study Nomenclature
... the `ate become… `ites – they all lose an oxygen.. -1 -2 -3 MnO2- CO22- PO33- ClO2- CrO32- SO32- NO2- but the charge remains the same
MnO- CO2- PO23- ClO- CrO22- SO22- NO- ... the `ate; the `ite; now the hypo- – subtract another oxygen !! -1 -2 -3 and the charge remains the same
MnO4- CO42- PO53- ClO4- CrO52- SO52- NO4- ... the `ate; the `ite;the hypo.. – lets add an oxygen … the Per- -1 -2 -3 and the charge remains the same
`ate `ite hypo- per- ClO4 perchlorate ClO3 chlorate ClO2 chlorite hypochlorite ClO
Determining Names and Formulas of Ionic Compounds Containing Polyatomic Ions 36. AlPO4 ______________________ 37. (NH4)2CO3 _______________________ 38. __________ lithium cyanide 39. ___________ copper(II) nitrate 40. KClO ______________________ 41. Zn(C2H3O2)2 ______________________ 42. __________ calcium phosphate 43. ___________ ammonium sulfite 44. __________ ammonium acetate 45. NaMnO4 _______________________
Naming Covalent Molecular Compounds Nonmetal to Nonmetal( or to the right of the zigzag red line) Use these Prefixes: Greek prefixes to indicate number (never use mono on first) mono - 1 di - 2 tri - 3 tetra - 4 penta - 5 hexa - 6 hepta - 7 octa - 8 nona - 9 deca – 10 boron trifluoride nitrogen monoxide Ex: BF3NO N2O5 dinitrogen pentoxide
PROBLEM: SOLUTION: Determining Names and Formulas of Covalent Compounds (a) What is the formula of carbon disulfide? (b) What is the name ofPCl5? (c) Give the name and formula of the compound whose molecules each consist of two N atoms and four O atoms. CS2 (a) Carbon is C, sulfide is sulfur S and di-means 2 • P is phosphorous, Cl is chloride, the prefix for 5 is penta-. Phosphorous pentachloride. • N is nitrogen and is in a lower group number than O (oxygen). • Therefore the formula is: • and the name is: N2O4 dinitrogen tetraoxide.
Naming Covalent Molecular Compounds 1. CO __________________________ 8. diphosphorus pentoxide _________________ 2. PBr3 ______________________________ 9. carbon dioxide _________________ 3. CCl4 ______________________________ 10. selenium trioxide _________________ 4. NCl3 ______________________________ 11. sulfur hexafluoride _________________ 5. SeO2 ______________________________ 12. phosphorus pentiodide ________________ 6. P2O3 _____________________________ 13. sulfur tribromide ________________ 7. NH3 ______________________________ 14. phosphorus hexachloride______________
Naming Compounds Acids acids - compounds that release H+ in water, must be (aq) - usually have H+ for the cation H+ reacts with water to produce H3O+ , called hydronium ion 1. acid's whose anions end in -ide use hydro___ic acid 2. acid's whose anions end in -ate use ___ic acid 3. acid's whose anions end in -ite use ___ous acid Ex HCl, H2CO3, HNO2, HNO3, HClO
Naming Compounds Hydrates hydrates – when certain compounds crystallize a particular number of water molecules are contained in the structure. - no moisture is apparent in these compounds water of hydration - water that is contained in hydrate - can be removed by heating anhydrous salt – hydrate after the water is removed ex CuSO45H2O CuSO4 + 5H2O hydrat anhydrous salt water Naming hydrates name salt and then (greek prefix) hydrate ex copper (II) sulfate pentahydrate
PROBLEM: Give the systematic names or the formulas for the names of the following compounds: (a) tin(II) fluoride (b) CrI3 (d) CoS (c) ferric oxide Sample Problem 2.7 Determining Names and Formulas of Ionic Compounds of Elements That Form More Than One Ion PLAN: Compounds are neutral. We find the smallest number of each ion which will produce a neutral formula. Use subscripts to the right of the element symbol. SOLUTION: (a) Tin (II) is Sn2+; fluoride is F-; so the formula is SnF2. (b) The anion I is iodide(I-); 3I- means that Cr(chromium) is +3. CrI3 is chromium(III) iodide (c) Ferric is a common name for Fe3+; oxide is O2-, therefore the formula is Fe2O3. (d) Co is cobalt; the anion S is sulfide(2-); the compound is cobalt (II) sulfide.
PROBLEM: Give the systematic names or the formula or the formulas for the names of the following compounds: (c) Ba(OH)2 8H2O Sample Problem 2.8 Determining Names and Formulas of Ionic Compounds Containing Polyatomic Ions (a) Fe(ClO4)2 (b) sodium sulfite PLAN: Note that polyatomic ions have an overall charge so when writing a formula with more than one polyatomic unit, place the ion in a set of parentheses. SOLUTION: (a) ClO4- is perchlorate; iron must have a 2+ charge. This is iron(II) perchlorate. (b) The anion sulfite is SO32- therefore you need 2 sodiums per sulfite. The formula is Na2SO3. (c) Hydroxide is OH- and barium is a 2+ ion. When water is included in the formula, we use the term “hydrate” and a prefix which indicates the number of waters. So it is barium hydroxide octahydrate.
PROBLEM: Something is wrong with the second part of each statement. Provide the correct name or formula. Sample Problem 2.9 Recognizing Incorrect Names and Formulas of Ionic Compounds (a) Ba(C2H3O2)2 is called barium diacetate. (b) Sodium sulfide has the formula (Na)2SO3. (c) Iron(II) sulfate has the formula Fe2(SO4)3. (d) Cesium carbonate has the formula Cs2(CO3). SOLUTION: (a) Barium is always a +2 ion and acetate is -1. The “di-” is unnecessary. (b) An ion of a single element does not need parentheses. Sulfide is S2-, not SO32-. The correct formula is Na2S. (c) Since sulfate has a 2- charge, only 1 Fe2+ is needed. The formula should be FeSO4. (d) The parentheses are unnecessary. The correct formula is Cs2CO3.
PROBLEM: Explain what is wrong with the name of the formula in the second part of each statement and correct it: Sample Problem 2.12 Recognizing Incorrect Names and Formulas of Binary Covalent Compounds (a) SF4 is monosulfur pentafluoride. (b) Dichlorine heptaoxide is Cl2O6. (c) N2O3 is dinitrotrioxide. SOLUTION: (a) The prefix mono- is not needed for one atom; the prefix for four is tetra-. So the name is sulfur tetrafluoride. (b) Hepta- means 7; the formula should be Cl2O7. (c) The first element is given its elemental name so this is dinitrogen trioxide.
12. Chromate CrO42- Example of polyatomic ions • Most common polyatomic ions
Groups/Families • 23, 24, 23, 23, 12, 2 • 1, 2 • 24, 13, 12 VIIIA IA IIA VIIA VA VIA Cr Mn Fe Co Ni Cu Zn Zn Zn +1 +2 -4 -3 -2 -1 0 +2 +3 +2 +4 +2 +3 +2 +3 +2 +3 +1 +2 +2 +4 +5 +3 Ag Cd I-VIIIB +1 +2 multiple charges Au Pt Hg Hg +2 +4 +1 +3 +1 +2
FeCl2 Fe Cl2iron (II) = 2+ Type II Binary Compounds FeCl3 iron(III) chloride FeCl2 iron(II) chloride FeCl2iron (II) = 2+ iron (II) = 2+ and iron (III) = 3+ ***Used only when:*** MORE THAN 1 POSITIVE CHARGE
CO3-2 carbonate CrO4-2 chromate OH- hydroxide Cr2O7-2 dichromate chlorate ClO3- O2-2 peroxide NO2- nitrite SO4-2 sulfate PO4-3 NO3- nitrate phosphate MnO4- permanganate Some Common Polyatomic Ions Formula Formula Name Name Cations ammonium NH4+ Common Anions acetate CH3COO- CN- cyanide