Across 1. A metal used in batteries but not pencil 2. This element is found in the most odorous compound 3. Its aqueous 2+ ion has a characteristic blue color 4. Bananas are rich in its cation 5. The noble gas with the second-lowest density 6. Its hydride is the most common basic gas 7. This metal forms a yellow oxyanion in basic solution 8. A gaseous nonmetal, X, that forms a tetraoxide, XO4 9. A transition metal. M. that forms a tetraoxide mo4 10. In a flame, its compounds produce a red-violet color. 11. Its diatomic molecule has the highest bond energy of any halogen 12. Named after Professor "e=mc2 13. A semimetal that forms a common solid dioxide 14. The metal used in the preparation of Grignard reagents 15. This element, X, forms such species as XF7and X3 16. The element first identified from the Suns spectrum 17. The 3+ ion of this rare earth element has the same electron con figuration as xenon 18. Other than xenon it is the only non-radioactive noble gas which is known to form chemical 19. Napoleon may have been poisoned by this element 20.This metal forms a colorless +l aqueous ion that gives a white precipitate with aqueous chloride ion 21. Its oxide is a good diamond substitute 22. This transition metal forms compounds that have anti-cancer activity 23. The alkali metal that resembles the alkaline earth metals in its chemistry. 24. Its sulfate is used for stomach X-rays 25. One of the allotropes of this nonmetal conducts heat five times better than copper 6. The densest gaseous element 27. This transition metal forms a very hard carbide 28. Its common 4+ ion has the electron configuration [Rn]5f 29. The"weak"metal of Group 15 30. Among the alkali metals. this clement has the most soluble fluoride and the least soluble 31. The sulfide of this transition metal is an excellent lubricant 32. Emperor Napoleon III used tableware of this metal for special state occasions 282
282 Across 1. A metal used in batteries but not pencils. 2. This element is found in the most odorous compounds. 3. Its aqueous 2+ ion has a characteristic blue color. 4. Bananas are rich in its cation. 5. The noble gas with the second-lowest density. 6. Its hydride is the most common basic gas. 7. This metal forms a yellow oxyanion in basic solution. 8. A gaseous nonmetal, X, that forms a tetraoxide, XO4. 9. A transition metal, M, that forms a tetraoxide, MO4. 10. In a flame, its compounds produce a red-violet color. 11. Its diatomic molecule has the highest bond energy of any halogen. 12. Named after Professor "e = mc2.'' 13. A semimetal that forms a common solid dioxide. 14. The metal used in the preparation of Grignard reagents. 15. This element, X, forms such species as XF7 and X3 − . 16. The element first identified from the Sun's spectrum. 17. The 3 + ion of this rare earth element has the same electron con figuration as xenon. 18. Other than xenon, it is the only non-radioactive noble gas which is known to form chemical compounds. 19. Napoleon may have been poisoned by this element. 20. This metal forms a colorless +1 aqueous ion that gives a white precipitate with aqueous chloride ion. 21. Its oxide is a good diamond substitute. 22. This transition metal forms compounds that have anti-cancer activity. 23. The alkali metal that resembles the alkaline earth metals in its chemistry. 24. Its sulfate is used for stomach X-rays. 25. One of the allotropes of this nonmetal conducts heat five times better than copper. 26. The densest gaseous element. 27. This transition metal forms a very hard carbide. 28. Its common 4+ ion has the electron configuration [Rn]5f 4. 29. The "weak" metal of Group 15. 30. Among the alkali metals, this clement has the most soluble fluoride and the least soluble iodide. 31. The sulfide of this transition metal is an excellent lubricant. 32. Emperor Napoleon III used tableware of this metal for special state occasions
Down 1. This member of Group i3 melts at only 30C 2. This nonmetal forms ionic, metallic, and covalent compounds 3. The 2+ ion of this rare earth metal has a half-filled set of forbitals 4.The"Tyrannosaurus rex"of the elements. 5. Its compounds were once used to produce glow-in-the-dark watches 6. This rare earth element was very difficult to separate from its neighbor, praseodymiu 7. Named after the"father"of the periodic table 8. The bottom member of Group 2, alphabetically 9. An organometallic compound of this main group metal is used in the preservation of books 10. The only metal to commonly form a diatomic cation in solution 11. This metal forms a magnetic oxide of formula M3O4 12. This gaseous element was once known as"dephlogisticated air 13. One allotrope is stored under water 14. Its hexaaqua ion in the +2 oxidation state is pink 15. This actinoid is usually sold as a compound known as"yellow cake 16. Xerography would be impossible without this element 17. Its common oxyanion has a characteristic purple color 18. The densest non-radioactive metal of Group 9 19. The highest atomic number element for which stable isotopes are known 20. The only liquid nonmetal at SATP 21. Its carbonate is one of the common minerals on the surface of the earth 22. The least electronegative of the halogens 23. A"borderline"metal that has a high transparency to X-rays 24. A purification process for this metal uses a tetracarbonyl compound 25. The atmospheric gas with the third highest concentration 26. Its simplest hydride is a dimer while its common fluoride is electron deficient 7. This metal suffers from a plague at low temperatures 28. A compound of this metal, auranofin, is used in the treatment of arthritis 29. The sulfide of this metal has an intense yellow color, hence its use as a pigment 30. Discovered by Sir Humphry Davy 83
283 Down 1. This member of Group i3 melts at only 30℃. 2. This nonmetal forms ionic, metallic, and covalent compounds. 3. The 2 + ion of this rare earth metal has a half-filled set of f orbitals. 4. The "Tyrannosaurus rex" of the elements. 5. Its compounds were once used to produce glow-in-the-dark watches. 6. This rare earth element was very difficult to separate from its neighbor, praseodymium. 7. Named after the "father" of the periodic table. 8. The bottom member of Group 2, alphabetically. 9. An organometallic compound of this main group metal is used in the preservation of books. 10. The only metal to commonly form a diatomic cation in solution. 11. This metal forms a magnetic oxide of formula M3O4. 12. This gaseous element was once known as "dephlogisticated air." 13. One allotrope is stored under water. 14. Its hexaaqua ion in the +2 oxidation state is pink. 15. This actinoid is usually sold as a compound known as "yellow cake." 16. Xerography would be impossible without this element. 17. Its common oxyanion has a characteristic purple color. 18. The densest non-radioactive metal of Group 9. 19. The highest atomic number element for which stable isotopes are known. 20. The only liquid nonmetal at SATP. 21. Its carbonate is one of the common minerals on the surface of the Earth. 22. The least electronegative of the halogens. 23. A "borderline" metal that has a high transparency to X-rays. 24. A purification process for this metal uses a tetracarbonyl compound. 25. The atmospheric gas with the third highest concentration. 26. Its simplest hydride is a dimer while its common fluoride is electron deficient. 7. This metal suffers from a plague at low temperatures. 28. A compound of this metal, auranofin, is used in the treatment of arthritis. 29. The sulfide of this metal has an intense yellow color, hence its use as a pigment. 30. Discovered by Sir Humphry Davy
APPENDI 2 Thermodynamic Properties of some Selected inorganic As thermodynamic data are experimental, their values differ from one source to another. A consistent set of values have been used here, summarized from G. Aylward and T. Findlay, Chemical Data, 3rd ed, New York: Wiley, 1994 △H Name Formula (kJ-mol-) (J. mol-.K-)(kJ. mol-) Aluminum Al(s) -538 aluminate ion Al(OH)4(aq) 1305 bromide AlBr3(s) 629 chloride hexahydrate AlCI3·6H2O(s) 318 AlF3(s) -143 All3(s) 314 159 -301 nitride AIN(S) 318 287 Al2O3(s) -1676 phosphate AlPO(s) -1734 -1618 Al2(so4)3(s) 3441 NH4 (aq) -133 +l11 NH4 Br(s) +113 loride NAcL(s) 314 +95 fluoride NH4F(S) iodide NHal(s) +117
284 As thermodynamic data are experimental, their values differ from one source to another. A consistent set of values have been used here, summarized from G. Aylward and T. Findlay, SI Chemical Data, 3rd ed., New York: Wiley, 1994. Compound H ~ S ~ G Name Formula (kJ·mol−1 ) (J·mol−l·K−1 ) (kJ·mol−1 ) Aluminum Al(s) 0 +28 0 Al(g) +330 +165 +290 Al3+(aq) −538 −325 −492 aluminate ion Al(OH)4 − (aq) −1502 +103 −1305 bromide AlBr3(s) −511 +180 −489 carbide Al4C3(s) −209 +89 −196 chloride AlCl3(s) −704 +111 −629 chloride hexahydrate AlCI3·6H20(s) −2692 +318 −2261 fluoride AlF3(s) −1510 +66 −1431 iodide AlI3(s) −314 +159 −301 nitride AlN(s) −318 +20 −287 oxide Al2O3(s) −1676 +51 −1582 phosphate AlPO4(s) −1734 +91 −1618 sulfate Al2(SO4)3(s) −3441 +239 −3100 Ammonium NH4 + (aq) −133 +111 −79 bromide NH4Br(s) −271 +113 −175 chloride NH4CI(s) −314 +95 −203 fluoride NH4F(s) −464 +72 −349 iodide NH4I(s) −201 +117 −113
nitrate NH4NO3 (s) +151 NH4)2SO4(s) +220 902 NH4VO3(s) +141 Antimony nacho SbCls() +301 -350 Sb2o5(s) 972 829 SbBr(s) trihydride Sbh3(g) triodide 215 trioxide Sb2O3(s) +110 -634 trisulfide Sb2S3(s) 174 Arsenic As(s)(grey) Asg) 302 +261 tafluorid AsFs(g) -1237 +317 l170 AS2O5(s) +105 AsBr3(s) trichloride AsCl3(D) -305 +216 trifluoride AsF3(D) 786 +289 trihydride(arsine) AsH3 (g) triiodide Asl3(s) +213 trioxide AS2O3(s) -576 trisulfide AS2S3(s) -169 +63 +180 Baf(ag) 10 bromide BaBri(s) 737 BaCO3(s) +112 Bacl2(s) 859 810 chloride dihydrate BaCl2·2H2O(s) fluoride BaF2(s) 1207 hydroxide Baloh)2(s) +101 856 hydroxide octahydrate a(OH)z·8H2O(s) 3342 -2793 iodide Balz(s) 605 +165 285
285 nitrate NH4NO3(s) −366 +151 −184 sulfate (NH4)2SO4(s) −1181 +220 −902 vanadate NH4VO3(s) −1053 +141 −888 Antimony Sb(s) 0 +46 0 Sb(g) +262 +180 +222 pentachloride SbCl5(l) −440 +301 −350 pentaoxide Sb2O5(s) −972 +125 −829 tribromide SbBr3(s) −259 +207 −239 trichloride SbCl3(s) −382 +184 −324 trihydride SbH3(g) +145 +233 +148 triodide SbI3(s) −100 +215 −99 trioxide Sb2O3(s) −720 +110 −634 trisulfide Sb2S3(s) −175 +182 −174 Arsenic As(s) (grey) 0 +35 0 As(g) +302 +174 +261 pentafluoride AsF5(g) −1237 +317 −1170 pentaoxide As2O5(s) −925 +105 −782 tribromide AsBr3(s) −130 +364 −159 trichloride AsC13(l) −305 +216 −259 trifluoride AsF3(l) −786 +289 −771 trihydride (arsine) AsH3(g) +66 +223 +69 triiodide AsI3(s) −58 +213 −59 trioxide As2O3(s) −57 +107 −576 trisulfide As2S3(s) −169 +164 −169 Barium Ba(s) 0 +63 0 Ba(g) +180 +170 +146 Ba2+ (aq) −538 +10 −561 bromide BaBr2(s) −757 +146 −737 carbonate BaCO3(s) −216 +112 −1138 chloride BaCl2(s) −859 +124 −810 chloride dihydrate BaCl2·2H2O(s) −1460 +203 −1296 fluoride BaF2(s) −1207 +96 −1157 hydroxide Ba(OH)2(s) −945 +101 −856 hydroxide octahydrate Ba(OH)2·8H2O(s) −3342 +427 −2793 iodide BaI2(s) −605 +165 −601
nitrate Ba(NO3 )2(s) BasO4(s) -1473 sulfide Bas(s) ervllium 136 Be- f(aq) BeBr2(s) 356 337 fluoride BeF2(s) -1027 +53 -979 Be(oh)2(s) 815 iodide l2(s) +120 187 BeO(s) Bismuth Bi(s) chloride BiCl3(s) 379 +177 Bi2O3(s) oxide chloride BioCI(s) sulfide Bi2S3(s) -143 14l B(s) boric acid H3 BO3(s) B10H14(g) +32 216 diborane B2h6(g) +232 pentaborane(9) BsH(D) +172 tribromide BBr3(1) 230 BCl3(g) trifluoride BF3 (g -1119 B2O3(s) trisulfide (di-) B2S3(s) Bromic 152 86
286 nitrate Ba(NO3)2(s) −992 +214 −797 nitride Ba3N2(s) −363 +152 −292 oxide BaO(s) −554 +70 −525 peroxide BaO2(s) −634 sulfate BaSO4(s) −1473 +132 −1362 sulfide BaS(s) −460 +78 −456 Beryllium Be(s) 0 +9 0 Be(g) +324 +136 +287 Be2+ (aq) −383 −130 −380 bromide BeBr2(s) −356 +100 −337 chloride BeCl2 (s) −490 +83 −445 fluoride BeF2(s) −1027 +53 −979 hydroxide Be(OH)2(s) −903 +52 −815 iodide BeI2(s) −189 +120 −187 oxide BeO(s) −609 +14 −580 Bismuth Bi(s) 0 +57 0 chloride BiCl3(s) −379 +177 −315 oxide Bi2O3(s) −574 +151 −494 oxide chloride BiOCl(s) −367 +120 −322 sulfide Bi2S3(s) −143 +200 −141 Boron B(s) 0 0 6 B(g) +565 +153 +521 boric acid H3BO3(s) −1095 +90 −970 carbide B4C(s) −71 +27 −71 decaborane(14) B10H14(g) +32 +353 +216 diborane B2H6(g) +36 +232 +87 nitride BN(s) −254 +15 −228 pentaborane(9) B5H9(l) +43 +184 +172 tribromide BBr3(1) −240 +230 −238 trichloride BCl3(g) −404 +290 −389 trifluoride BF3(g) −1136 +254 −1119 trioxide (di-) B2O3(s) −1273 +54 −1194 trisulfide (di-) B2S3(s) −252 +92 −48 Bromine Br2(l) 0 +152 0 Br2(g) +31 +245 +3
Br(g) +112 +175 Br(aq) +83 bromate ion +19 hypobromite ion Bro(aq) BrCi(g) BrF(g) pentafluoride BrFs(g) rirluoriae BrF3(g) -256 Cadmium Cd(s) CaBr(s) 316 +137 carbonate CdCO(s) +92 chloride CdCl2(s) +115 fluoride CdF2(s) +77 hydroxide Cd(oh)2(s) 474 iodide Cdl2(s) nitrate Cd(NO3 )2(s) Cdo(s) 228 Caso4 (s) 933 Calcium a(s) +42 +178 155 CaBr2(s) -683 664 Cac2(s) CO3(s)(calcite) chloride Cacl2(s) +105 CaF2(s) -1220 hydride CaH2(s) -147 hydroxide Cal oh)2(s) +83 iodide Cal2(s) 529 nitrate Ca(NO )2(s) 938 +193 oxide Cao(s) Cas(PO4)2(s) 236 87
287 Br(g) +112 +175 +82 Br− (aq) −121 +83 −104 bromate ion BrO3 − (aq) −67 +162 +19 hypobromite ion BrO− (aq) −94 +42 −3 monochloride BrCl(g) +15 +240 −1 monofluoride BrF(g) −94 +229 −109 pentafluoride BrF5 (g) −429 +320 −351 trifluoride BrF3(g) −256 +293 −229 Cadmium Cd(s) 0 +52 0 Cd(g) +112 +168 +77 Cd2+ (aq) −76 −73 −78 bromide CdBr2(s) −316 +137 −296 carbonate CdCO3(s) −751 +92 −669 chloride CdCl2 (s) −391 +115 −344 fluoride CdF2 (s) −700 +77 −648 hydroxide Cd(OH)2(s) −561 +96 −474 iodide CdI2(s) −203 +161 −201 nitrate Cd(NO3)2(s) −456 oxide CdO(s) −258 +55 −228 sulfate CdSO4(s) −933 +123 −823 sulfide CdS(s) −162 +65 −156 Calcium Ca(s) 0 +42 0 Ca(g) +178 +155 +144 Ca2+ (aq) −543 −56 −553 bromide CaBr2(s) −683 +130 −664 carbide CaC2(s) −60 +70 −65 carbonate CaCO3(s) (calcite) −1207 +93 −1129 chloride CaCl2(s) −796 +105 −748 fluoride CaF2(s) −1220 +69 −1167 hydride CaH2(s) −186 +42 −147 hydroxide Ca(OH)2(s) −986 +83 −898 iodide CaI2(s) −533 +142 −529 nitrate Ca(NO3)2(s) −938 +193 −743 oxide CaO(s) −635 +38 −603 phosphate Ca3(PO4)2(s) −4121 +236 −3885
silicate Casio3(s) -1499 -1434 07 -1332 sulfate hemihydrate CaSO4·1/2H2Os) 131 sulfate dihydrate CaSO4·2H2O(s) -2023 +194 -1797 sulfide Cas(s) -482 Carbon C(s(graphite 717 158 +671 carbonate ion CO32( 675 COCI(g) +284 cyanide ion CN(aq) dioxide CO2(g) 394 +214 394 dioxide CO(aq) -413 +119 disulfide CS2(1) +65 C2h6(g) hydrogen carbonate ion HCO(aq) -587 CHa(g) tetrabromide CBra(s) +213 etrachloride CCd) 135 216 tetrafluoride CFa(g) Cesium +85 176 bromide CsBr(s) +113 391 CS2CO3(s) +204 1054 chloride CsCl(s) +101 Cs2SO4(s) Chlorine Cl2(g)
288 silicate CaSiO3(s) −1567 +82 −1499 sulfate CaSO4(s) −1434 +107 −1332 sulfate hemihydrate CaSO4·1/2H2O(s) −1577 +131 −1437 sulfate dihydrate CaSO4·2H2O(s) −2023 +194 −1797 sulfide CaS(s) −482 +56 −477 Carbon C(s) (graphite) 0 +6 0 C(s) (diamond) +2 +2 +3 C(g) +717 +158 +671 carbonate ion CO3 2− (aq) −675 −50 −528 chloride (-yl) (phosgene) COCl2(g) −219 +284 −205 cyanide ion CN− (aq) +151 +94 +172 dioxide CO2(g) −394 +214 −394 dioxide CO2(aq) −413 +119 −386 disulfide CS2(l) +90 +151 +65 ethane C2H6(g) −85 +230 −33 hydrogen carbonate ion HCO3 − (aq) −690 +98 −587 methane CH4(g) −75 +186 −51 monoxide CO(g) −111 +198 −137 tetrabromide CBr4(s) +19 +213 +48 tetrachloride CCl4(l) −135 +216 −65 tetrafluoride CF4(g) −933 +262 −888 thiocyanate ion NCS− (aq) +76 +144 +93 Cesium Cs(s) 0 +85 0 Cs(g) +76 +176 +49 Cs+ (aq) −258 +132 −291 bromide CsBr(s) −406 +113 −391 carbonate Cs2CO3(s) −1140 +204 −1054 chloride CsCl(s) −443 +101 −415 fluoride CsF(s) −554 +93 −526 iodide CsI(s) −347 +123 −341 nitrate CsNO3(s) −506 +155 −407 sulfate Cs2SO4(s) −1443 +212 −1324 Chlorine Cl2(g) 0 +223 0 C12(aq) −23 +121 +7 Cl(g) +121 +165 +105
chlorate ion CIO3(aq) CIO2(g) +257 hypochlorite ion Clo(ag +42 CiF(g) 218 oxide(di-) C120(g) 266 perchlorate ion CIO(aq) bifluoride CIF3(g +282 123 Chromium Cr(s) 175 352 139 Cr(aq) 256 205 (l) chloride CrCl2(s) +115 356 (ln) chloride CrCl3(s) +123 chromate ion CrO4(aq) 881 dichromate ion Cr2O7(aq) -1490 +262 1301 (Ill)oxide Cr2O3(s) -1140 -1058 (VI)oxide CrO3(s) -513 (lll) sulfate Cr2(SO4)3(s) 2911 Cobalt Co(s) Co(g) +380 Co(aq) -113 (n carbonate CoCO3 (s) 713 637 (n chloride CoCl(s) -313 (n chloride COCl2·6H2O(s) 2115 -1725 (n hydroxide Co(OH)2(s)(pink) CoO(s) (n) sulfate CoSO4(s) +118 (I sulfate heptahydrate CoSO·7H2O(s) Cu(g) Cu(aq) +6
289 Cl− (aq) −167 +57 −131 chlorate ion ClO3 − (aq) −104 +162 −8 dioxide ClO2(g) +102 +257 +120 hypochlorite ion ClO− (aq) −107 +42 −37 monofluoride CIF(g) −54 +218 −56 oxide (di-) C12O(g) +80 +266 +98 perchlorate ion ClO4 − (aq) −128 +184 −8 trifluoride ClF3(g) −163 +282 −123 Chromium Cr(s) 0 +24 0 Cr(g) +397 +175 +352 Cr2+ (aq) −139 −165 Cr3+ (aq) −256 −205 (II) chloride CrC12(s) −395 +115 −356 (III) chloride CrCl3(s) −556 +123 −486 chromate ion CrO4 − (aq) −881 +50 −728 dichromate ion Cr2O7 2− (aq) −1490 +262 −1301 (III) oxide Cr2O3(s) −1140 +81 −1058 (VI) oxide CrO3(s) −580 +72 −513 (III) sulfate Cr2(SO4)3(s) −2911 +259 −2578 Cobalt Co(s) 0 +30 0 Co(g) +425 +180 +380 Co2+(aq) −58 −113 −54 Co3+(aq) +92 −305 +134 (II) carbonate CoCO3(s) −713 +89 −637 (II) chloride CoCl2(s) −313 +109 −270 (II) chloride hexahydrate COC12·6H2O(s) −2115 +343 −1725 (II) hydroxide Co(OH)2(s) (pink) −540 +79 −454 (II) oxide CoO(s) −238 +53 −214 (II) sulfate CoSO4(s) −888 +118 −782 (II) sulfate heptahydrate CoSO4·7H2O(s) −2980 +406 −2474 Copper Cu (s) 0 +33 0 Cu(g) +337 +166 +298 Cu+ (aq) +72 +41 +50 Cu2+(aq) +65 −98 +65
chloride CuCI(s) (II)chloride CuCl(s) 220 76 (n) chloride dihydrate CuCl2·2H2O(s) (II) hydroxide Cu(oh)2(s) -450 (I)oxide Cu2O(s) 169 (I) oxide 130 (II) sulfate CuSO4(s) +109 CuSO4·5H2O(s) 1880 (I)sulfide (II)sulfide fluorine (g) 203 F(g) +79 +62 F(aq) 335 Gallium +41 Ga(g) +277 +169 Ga t(aq) 212 331 bromide GaBr3(s) chloride GaCl3(s) +142 fluoride GaF3(s) -1163 iodide Gal3 (s) -236 ide Ga2O3(s) +85 germanium Ge(s) Ge(g) 372 +331 dioxide GeO(s) 237 tetrachloride -496 +348 tetraoxide GeO(s) Hydrogen +131 H(g) +218 +115 +203 HBr(g) HCl(g) 7 fluoride +174 hydrobromic acid HBr(aq) hydrochloric acid 67 56 hydrofluoric acid 279 90
290 (I) chloride CuCl(s) −137 +86 −120 (II) chloride CuCl2(s) −220 +108 −176 (II) chloride dihydrate CuCl2·2H2O(s) −821 +167 −656 (II) hydroxide Cu(OH)2(s) −450 +108 −373 (I) oxide Cu2O(s) −169 +93 −146 (II) oxide CuO(s) −157 +43 −130 (II) sulfate CuSO4(s) −771 +109 −662 (II) sulfate pentahydrate CuSO4·5H2O(s) −2280 +300 −1880 (I) sulfide Cu2S(s) −80 +121 −86 (II) sulfide CuS(s) −53 +67 −54 Fluorine F2(g) 0 +203 0 F(g) +79 +159 +62 F − (aq) −335 −14 −281 Gallium Ga(s) 0 +41 0 Ga(g) +277 +169 +239 Ga3+ (aq) −212 −331 −159 bromide GaBr3(s) −387 +180 −360 chloride GaCl3(s) −525 +142 −455 fluoride GaF3(s) −1163 +84 −1085 iodide GaI3(s) −239 +204 −236 oxide Ga2O3(s) −1089 +85 −998 Germanium Ge(s) 0 +31 0 Ge(g) +372 +168 +331 dioxide GeO(s) −262 +50 −237 tetrachloride GeCl4(g) −496 +348 −457 tetraoxide GeO2(s) −580 +40 −521 Hydrogen H2(g) 0 +131 0 H(g) +218 +115 +203 H+ (aq) 0 0 0 bromide HBr(g) −36 +199 −53 chloride HCl(g) −92 +187 −95 fluoride HF(g) −273 +174 −275 hydrobromic acid HBr(aq) −122 +82 −104 hydrochloric acid HCl(aq) −167 +56 −131 hydrofluoric acid HF(aq) −333 −14 −279