Unit 4. Inorganic formulation

Transcription

1 Index Unit 4. Inorganic formulation 1. STICHIMETRIC NAMES F BINARY CMPUNDS With multiplying prefix With oxidation numbers With charge number Special names...6 Chemistry exercises on Inorganic Nomenclature...11 Practice exam...14 Periodic Table with xidation Numbers. Table III...15 Page 1 of 15

2 1. STICHIMETRIC NAMES F BINARY CMPUNDS With multiplying prefix When constructing a stoichiometric name for a binary compound, one element is designated as the electropositive constituent and the other the electronegative constituent. The electropositive constituent is by convention the element that occurs last in the sequence of Table I and its name is the unmodified element name. The name of the electronegative constituent is constructed by modifying the element name with the ending ide, The stoichiometric name of the compound is then formed by combining the name of the electropositive constituent, cited first, with that of the electronegative constituent, both suitably qualified by any necessary multiplicative prefixes (Table II) The multiplicative prefixes precede the names they multiply, and are joined directly to them without spaces or hyphens. The final vowels of multiplicative prefixes should not be elided (although monoxide, rather than monooxide,is an allowed exception because of general usage). The two parts of the name are separated by a space in English. Prefix + name of 1st element in the formula Prefix + stem of 2nd element + ide Table II--Prefixes for number of atoms Number of atoms Prefix 1 mon 2 di 3 tri 4 tetra or tetr* 5 penta or pent* 6 hexa or hex* 7 hepta or hept* Page 2 of 15

3 *The first spelling is used if the stem of the element begins with a consonant and the second spelling if the stem of the element begins with a vowel. The stem of an element is formed by dropping the last syllable of the element's name. Prefixes are assigned by the number of atoms of each element in the formula, and the prefix corresponding to a given number of atoms can be found Table II. The prefix "mon" is dropped with the exception of carbon monoxide, and the suffix "ide" is used with all two element compounds. Carbon dioxide is a familiar example of a systematic name. Example 1--What is the formula of sulfur hexafluoride? The elements composing the compound are S and F. Also the prefix hex says there are 6 F atoms so the formula is SF 6. Example 2--Name the compound N 2 4 The name is dinitrogen tetroxide With oxidation numbers When constructing a stoichiometric name for a binary compound, one element is designated as the electropositive constituent and the other the electronegative constituent. The electropositive is the unmodified element name. The name of the electronegative constituent is constructed by modifying the element name with the ending ide, The electropositive constituent, cited first, is followed by a roman numeral between parentheses, just in the case that this element has more than one oxidation number in the table III. The two parts of the name are separated by a space in English. Name the electropositive element (roman numerals if they have more than one) followed by the stem name of the electronegative with an -ide ending. Examples: NaCl = sodium chloride S 3 = sulfur(vi) oxide Ca = calcium oxide CaF 2 = calcium fluoride Cu = copper(ii) oxide Page 3 of 15

4 If you know the name and you want to write the formula then it is more complex. This system does not use prefixes and assumes a knowledge of the law of electrical neutrality, the octet rule, and ionic theory. It will be very helpful use the table III of the oxidation numbers. Example 2- What is the chemical formula of cesium sulfide? The compound is composed of cesium and sulfur. From Table, we have Cs has + 1 S has - 2 Cs 2 S. Note the ions composing cesium sulfide are Cs + and S 2. If the metal exhibits more than one oxidation state, the oxidation state of the metal, in the compound of interest, is indicated by a Roman numeral placed in parentheses following the name of the metal. The Roman numeral equals the charge on the metal ion. The following examples show how the names in these compounds are assigned and used to determine the chemical formula from the name. Example 1--The color of ruby and sapphire is due to a small quantity of Cr 2 3 in these gem stones. What is the systematic name of Cr 2 3? The name of the compound is Chromium(III) oxide. Example 2--The compound Lead(IV) oxide is used in car batteries. What is the chemical formula of Lead(IV) oxide? Pb has + 4 (from Lead(IV)) has -2 (from Table III) The chemical formula is Pb 2. Example 3.- What is the name of HgBr? Bromine has number -1 (the last element always with the negative oxidation number) (see table III) mercury can have oxidation numbers of and. All the compounds are neutral so the oxidation number of mercury has to be It is named mercury(i) bromide For similar reasons HgBr 2 is named mercury(ii) bromide Page 4 of 15

5 1.3.- With charge number When constructing a stoichiometric name for a binary compound, one element is designated as the electropositive constituent and the other the electronegative constituent. The electropositive constituent is by convention the element that occurs last in the sequence of Table I and its name is the unmodified element name. The name of the electronegative constituent is constructed by modifying the element name with the ending ide, The electropositive constituent, cited first, is followed by an Arabic number and a plus sign (+) between parentheses, just in the case that this element has more than one oxidation number in the table III. The two parts of the name are separated by a space in English. Name the electropositive element (Arabic numbers (+)if they have more than one) followed by the stem name of the electronegative with an -ide ending. Examples: NaCl = sodium chloride Ca = calcium oxide CaF 2 = calcium fluoride Cu = copper(2+) oxide If you know the name and you want to write the formula then it is more complex. This system does not use prefixes and assumes a knowledge of the law of electrical neutrality, the octet rule, and ionic theory. It will be very helpful use the table III of the oxidation numbers. Example 1--The color of ruby and sapphire is due to a small quantity of Cr 2 3 in these gem stones. What is the systematic name of Cr 2 3? The name of the compound is Chromium(3+) oxide. Example 2--The compound Lead(4+) oxide is used in car batteries. What is the chemical formula of Lead(4+) oxide? Pb has + 4 (from Lead(4+)) has -2 (from Table III) The chemical formula is Pb 2. Example 3.- What is the name of HgBr? Page 5 of 15

6 Bromine has number -1 (the last element always with the negative oxidation number) (see table III) mercury can have oxidation numbers of and. All the compounds are neutral so the oxidation number of mercury has to be It is named mercury(1+) bromide For similar reasons HgBr 2 is named mercury(2+) bromide 2. Special names Some binary compounds have an special and traditional name and this is the name that we usually are going to use. H 2 NH 3 CH 4 water ammonia methane Binary acids consist of hydrogen combined with an element of the groups VI or VII. Binary acids are named by using the prefix hydro- followed by the stem name of the non-metal element (the second element in the formula) with an -ic ending. The name is followed by the word acid. Examples: HCl is named hydrochloric acid HBr is named hydrobromic acid HI is named hydroiodic acid H 2 S is named hydrosulfuric acid Page 6 of 15

7 If I have the name and I have to say the formula... 1) chlorine monoxide 2) oxygen difluoride 3) boron phosphide 4) dinitrogen monoxide 5) nitrogen trifluoride 6) sulfur tetrachloride 7) selenium trioxide 8) carbon dioxide 9) diphosphorous pentoxide 10) phosphorous trichloride 11) sulfur dioxide 12) bromine pentafluoride 13) disulfur dichloride 14) boron trifluoride 15) dinitrogen tetroxide 16) silicon tetrachloride 17) magnesium difluoride 18) chlorine monoxide 19) silicon dioxide 20) boron trichloride 21) dinitrogen pentasulfide 22) carbon monoxide 23) sulfur trioxide 24) dinitrogen trioxide 25) dinitrogen monoxide 26) Lithium chloride 27) sulfur hexafluoride 28) phosphorous pentachloride 29) nitrogen monoxide 30) aluminum trichloride 31) Tellurium dioxide 32) diantimony trioxide 33) hydrogen fluoride 34) Dinitrogen trisulfide Page 7 of 15

8 If I have the formula and I have to say the name using multiplying prefix... 1) S 2 2) PBr 3 3) Ba 3 N 2 4) Al 2 3 5) I 2 6) SrF 2 7) Li 2 S 8) 7 Cl 2 9) C 2 10) AlP 11) K 2 S 12) LiBr 13) Sr 3 P 2 14) BaCl 2 15) NaBr 16) MgF 2 17) Na 2 18) N 2 19) Si 2 20) PCl 5 21) Cs 2 22) SF 6 23) Mg 24) CaBr 2 25) LiI Page 8 of 15

9 If I have the name and I have to say the formula... 1) chlorine(vii) oxide 2) sodium phosphide 3) boron phosphide 4) nitrogen(iv) oxide 5) gold(iii) fluoride 6) Tin(IV) chloride 7) nickel(ii) oxide 8) magnesium oxide 9) phosphorous(v) oxide 10) potassium chloride 11) aluminum oxide 12) cobalt(iii) fluoride 13) lead(iv) chloride 14) boron fluoride 15) silver oxide 16) barium chloride 17) magnesium fluoride 18) beryllium hydride 19) calcium sulfide 20) boron chloride 21) iron(iii) selenide 22) iron(ii) bromide 23) cobalt(ii) oxide 24) mercury(i) nitride 25) zinc chloride 26) Lithium chloride 27) gold(iii) oxide 28) tin(ii) chloride 29) rubidium oxide 30) aluminum chloride 31) cadmium oxide 32) cesium oxide 33) calcium hydride 34) strontium sulfide Page 9 of 15

10 If I have the formula and I have to say the name using oxidation numbers... 1) MgS 2) KBr 3) Ba 3 N 2 4) Al 2 3 5) NaI 6) SrF 2 7) Li 2 S 8) FeCl 2 9) Ca 10) AlP 11) Au 2 S 12) HgBr 13) Sr 3 P 2 14) CoCl 2 15) NaBr 16) ZnF 2 17) Na 2 18) NiS 19) FeN 20) AlN 21) Cs 2 22) RbI 23) Fe 24) CaBr 2 25) LiI 26) BeBr 2 27) K 2 28) SnI 2 29) PbF 4 30) Al 2 S 3 Page 10 of 15

11 Chemistry exercises on Inorganic Nomenclature 1. Name the following using multiplying prefixes: a) S 3 b) C 2 c) 5 Cl 2 d) 7 Br 2 e) I 2 f) S 2 g) N 2 h) P Write the formula for: a) phosphorus pentachloride b) carbon monoxide c) dinitrogen trioxide d) phosphorus trichloride e) heptoxygen dichloride f) lead dioxide g) sulfur trioxide h) diphosphorus pentoxide 3. Name the following using oxidation numbers: a)asf 3 b)al 2 S 3 c)pb 2 d)cocl 2 e) Cu 4. Write the formula for a)gold(iii) chloride b)strontium fluoride c)sodium oxide Page 11 of 15

12 d) Dinitrogen pentoxide e)potassium sulfide 5. Write the formula a) nickel (III) sulfide b) carbon dioxide c) sodium chloride d) silver iodide e) calcium oxide f) mercury(i) bromide g) cobalt(ii) chloride h) iron(iii) chloride 6. Write the chemical formula: a) ammonia b) water c) methane d) hydrochloric acid e) hydrosulfuric acid 7. Write the name of the following: a) HBr b) HI c) H2S d) NH3 8. Write the chemical formula: a) Chlorine(VII) oxide b) Tin(4+) oxide c) copper(2+) oxide d) disodium oxide e) sulfur trioxide Page 12 of 15

13 f) barium oxide g) barium dihydride h) copper(i) hydride I) carbon disulfide j) carbon(4+) chloride k) phosphorus(v) chloride l) Strontium sulfide m) boron trichloride n) iron(iii) sulfide o) barium chloride p) mercury(2+) hydride q) potassium selenide 9. Name using multiplying prefix and oxidation numbers: a) Fe 2 S 3 b) Na 2 S c) KBr d) HgCl 2 e) HI f) S 2 g) Pb 2 h) Li 2 I) Au(H) 3 j) Sn Page 13 of 15

14 Practice exam 1.- Write the names of the following compounds in both ways: 1. HgH 2 2. FeCl 3 3. P CsH 5. CaSe 6. SrBr 2 7. HCl 8. Te 3 9. Li N Na 2Se 12. 7Br B 2S Au NH CaF CuH 18. KI 19. NaCl 20. NiI Write the chemical formula: 21. Tin(IV) oxide 22. Iron(III) oxide 23. aluminum hydride 24. sulfur (VI) oxide 25. sulphur trioxide 26. cobalt(iii) bromide 27. phosphorus pentachloride 28. methane 29. Beryllium oxide 30. potassium hydride 31. magnesium nitride 32. lead(ii) sulfide 33. calcium hydride 34. heptoxygen diiodide 35. carbon dioxide 36. strontium bromide 37. silicon tetrahydride 38. gold(iii) iodide 39. zinc phosphide 40. copper(ii) hydride Page 14 of 15

15 Periodic Table with xidation Numbers. Table III 1A 2A 3B 4B 5B 6B 7B 8B 1B 2B 3A 4A 5A 6A 7A 8A 1 H -1 3 Li 4 Be 5 B 6 C -4 7 N F Na 12 Mg 13 Al 14 Si P S Cl K 20 Ca 26 Fe 27 Co 28 Ni 29 Cu 30 Zn 33 As Se Br Rb 38 Sr 46 Pd 47 Ag 48 Cd 50 Sn 51 Sb Te I Cs 56 Ba 78 Pt 79 Au 80 Hg 82 Pb Page 15 of 15