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{{chembox |
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| verifiedrevid = 411086441 |
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| verifiedrevid = 442343539 |
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| ImageFile = Lead dioxide.jpg |
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| ImageFile = Lead dioxide.jpg |
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| ImageSize = 200px |
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| ImageSize = |
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| ImageName = Sample of lead dioxide |
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| ImageName = Sample of lead dioxide |
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| ImageFile2 = Oxid olovičitý.PNG |
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| ImageFile2 = Oxid olovičitý.PNG |
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| ImageSize2 = 100px |
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| ImageSize2 = 200px |
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| ImageName2 = Sample of lead dioxide |
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| ImageName2 = Sample of lead dioxide |
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| IUPACName = Lead(IV) oxide |
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| IUPACName = Lead(IV) oxide |
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| OtherNames = Plumbic oxide<br/>] |
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| OtherNames = Plumbic oxide<br/>] |
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| Section1 = {{Chembox Identifiers |
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|Section1={{Chembox Identifiers |
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| CASNo = 1309-60-0 |
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| CASNo = 1309-60-0 |
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| CASNo_Ref = {{cascite}} |
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| CASNo_Ref = {{cascite|correct|CAS}} |
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| UNII_Ref = {{fdacite|correct|FDA}} |
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| PubChem = |
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| UNII = 7JJD3ICL6A |
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| ChemSpiderID = 14109 |
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| ChemSpiderID1 = 11421764 |
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| EC_number = 215-174-5 |
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| PubChem = 14793 |
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| UNNumber = 1872 |
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| UNNumber = 1872 |
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| RTECS = OGO700000 |
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| RTECS = OGO700000 |
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}} |
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}} |
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| Section2 = {{Chembox Properties |
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|Section2={{Chembox Properties |
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| Formula = PbO<sub>2</sub> |
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| Formula = {{chem2|PbO2}} |
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| MolarMass = 239.2 g/mol |
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| MolarMass = 239.1988 g/mol |
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| Appearance = black powder |
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| Appearance = dark-brown, black powder |
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| Density = 9.38 g/cm<sup>3</sup> |
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| Density = 9.38 g/cm<sup>3</sup> |
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| MeltingPt = 290 °C decomp. |
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| MeltingPtC = 290 |
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| MeltingPt_notes = decomposes |
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| Solubility = insoluble |
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| Solubility = insoluble |
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| SolubleOther = soluble in ] <br> insoluble in ] |
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| RefractIndex = 2.3 |
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| Section3 = {{Chembox Structure |
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|Section3={{Chembox Structure |
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| Coordination = |
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| Coordination = |
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| CrystalStruct = |
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| CrystalStruct = hexagonal |
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| Section7 = {{Chembox Hazards |
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|Section7={{Chembox Hazards |
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| ExternalMSDS = |
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| ExternalSDS = |
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| GHSPictograms = {{GHS03}}{{GHS07}}{{GHS08}}{{GHS09}} |
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| EUIndex = 082-001-00-6 |
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| GHSSignalWord = Danger |
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| EUClass = Repr. Cat. 1/3<br/>Harmful ('''Xn''')<br/>Dangerous for the environment ('''N''') |
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| HPhrases = {{H-phrases|272|302|332|360|372|373|410}} |
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| RPhrases = {{R61}}, {{R20/22}}, {{R33}}, {{R62}}, {{R50/53}} |
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| PPhrases = {{P-phrases|201|202|210|220|221|260|261|264|270|271|273|280|281|301+312|304+312|304+340|308+313|312|314|330|370+378|391|405|501}} |
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| SPhrases = {{S53}}, {{S45}}, {{S60}}, {{S61}} |
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| NFPA-H = 3 |
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| NFPA-H = 4 |
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| NFPA-F = 0 |
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| NFPA-F = 0 |
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| NFPA-R = 1 |
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| NFPA-R = 3 |
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| NFPA-O = OX |
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| NFPA-S = OX |
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| FlashPt = Non-flammable |
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| FlashPt = Non-flammable |
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}} |
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| Section8 = {{Chembox Related |
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|Section8={{Chembox Related |
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| OtherAnions = |
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| OtherAnions = |
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| OtherCations = ]<br/>]<br/>]<br/>] |
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| OtherCations = ]<br/>]<br/>]<br/>] |
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| OtherFunctn = ]<br/>] |
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| OtherFunction = ]<br/>] |
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| Function = ] ]s |
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| OtherFunction_label = ] ]s |
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| OtherCpds = ]<br/>] |
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| OtherCompounds = ]<br/>] |
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'''Lead(IV) oxide''', commonly known as '''lead dioxide''', is an ] with the ] {{chem2|PbO2}}. It is an ] where ] is in an ] of +4.<ref>{{Cite journal|last1=Meek|first1=Terry L.|last2=Garner|first2=Leah D.|date=2005-02-01|title=Electronegativity and the Bond Triangle|journal=Journal of Chemical Education|volume=82|issue=2|pages=325|doi=10.1021/ed082p325|bibcode=2005JChEd..82..325M|issn=0021-9584}}</ref> It is a dark-brown solid which is insoluble in water.<ref name=en>{{cite book|url=https://books.google.com/books?id=Owuv-c9L_IMC&pg=PA590|page=590|title=Concise Encyclopedia of Chemistry|first=Mary|last=Eagleson|publisher=Walter de Gruyter|year=1994|isbn=978-3-11-011451-5}}</ref> It exists in two crystalline forms. It has several important applications in ], in particular as the positive plate of ]. |
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'''Lead dioxide''', PbO<sub>2</sub>, also '''plumbic oxide''' is an ] of ] in ] +4. It is an odorless dark-brown crystalline powder which is nearly insoluble in water. It exists in two crystalline forms. The alpha phase has ] symmetry; it has been first synthesized in 1941 and identified in nature as a rare mineral ] in 1988. On the contrary, the more prevailing, ] beta phase was first identified as the mineral ] around 1845 and later produced synthetically. Lead dioxide is a strong oxidizing agent which is used in the manufacture of matches, pyrotechnics, dyes and other chemicals. It also has several important applications in ], in particular as a component of ]. |
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==Properties== |
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==Properties== |
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===Physical=== |
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===Physical=== |
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] |
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] |
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] |
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] |
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Lead dioxide is an odorless dark-brown crystalline powder which is nearly insoluble in water.<ref name=en>{{cite book|url=http://books.google.com/?id=Owuv-c9L_IMC&pg=PA590|page=590|title=Concise encyclopedia chemistry|author=Mary Eagleson|publisher=Walter de Gruyter|year=1994|isbn=3110114518}}</ref> It has two major polymorphs, alpha and beta, which occur naturally as rare minerals ] and ], respectively. Whereas the beta form was known already in 1845<ref name=pl>Haidinger W (1845) , p. 500 in Handbuch der Bestimmenden Mineralogie Bei Braumüller and Seidel Wien pp. 499-506 (in German)</ref>, α-PbO<sub>2</sub> was first synthesized in 1941 and identified as a mineral only in 1988. The alpha form has ] symmetry, ] Pbcn (No. 60), ] oP12, lattice constants ''a'' = 0.497 nm, ''b'' = 0.596 nm, ''c'' = 0.544 nm, ''Z'' = 4 (four formula units per unit cell).<ref name=j1>{{cite journal|url=http://rruff.info/uploads/CM26_905.pdf |
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Lead dioxide has two major polymorphs, alpha and beta, which occur naturally as rare minerals ] and ], respectively. Whereas the beta form had been identified in 1845,<ref name=pl>{{cite book|last=Haidinger |first=W. |date=1845 |url=http://rruff.info/uploads/HBM1845_500.pdf |contribution=Zweite Klasse: Geogenide. II. Ordnung. Baryte VII. Bleibaryt. Plattnerit. |page=500 |title=Handbuch der Bestimmenden Mineralogie |publisher=Braumüller & Seidel |location=Vienna |language=de}}</ref> α-{{chem2|PbO2}} was first identified in 1946 and found as a naturally occurring mineral 1988.<ref name=j1>{{cite journal|url=http://rruff.info/uploads/CM26_905.pdf |
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|title=Scrutinyite, natural occurrence of α-PbO<sub>2</sub> from Bingham, New Mexico, U.S.A., and Mapimi, Mexico|year=1988|author=J. E. Taggard, Jr. ''et al.''|journal=Canadian Mineralogist|volume=26|page=905}}</ref> The symmetry of the beta form is ], ] P4<sub>2</sub>/mnm (No. 136), ] tP6, lattice constants ''a'' = 0.491 nm, ''c'' = 0.3385 nm, ''Z'' = 2.<ref>{{cite journal|doi=10.1107/S0021889881008959|title=Crystal data for β-PbO2|year=1981|last1=Harada|first1=H.|last2=Sasa|first2=Y.|last3=Uda|first3=M.|journal=Journal of Applied Crystallography|volume=14|pages=141}}</ref> |
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| title =Scrutinyite, natural occurrence of α-PbO<sub>2</sub> from Bingham, New Mexico, U.S.A., and Mapimi, Mexico|year=1988|first=J. E. Jr. |last=Taggard|journal=Canadian Mineralogist|volume=26|page=905|display-authors=etal}}</ref> |
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The alpha form has ] symmetry, ] Pbcn (No. 60), ] ''oP''12, lattice constants ''a'' = 0.497 nm, ''b'' = 0.596 nm, ''c'' = 0.544 nm, ''Z'' = 4 (four formula units per unit cell).<ref name=j1 /> The lead atoms are six-coordinate. |
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Lead dioxide decomposes upon heating in air as follows: |
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:PbO<sub>2</sub> → Pb<sub>12</sub>O<sub>19</sub> → Pb<sub>12</sub>O<sub>17</sub> → Pb<sub>3</sub>O<sub>4</sub> → PbO |
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The symmetry of the beta form is ], ] P4<sub>2</sub>/mnm (No. 136), ] ''tP''6, lattice constants ''a'' = 0.491 nm, ''c'' = 0.3385 nm, ''Z'' = 2<ref>{{cite journal|doi=10.1107/S0021889881008959|title=Crystal data for β-PbO<sub>2</sub>|year=1981|last1=Harada|first1=H.|last2=Sasa|first2=Y.|last3=Uda|first3=M.|journal=Journal of Applied Crystallography|volume=14|pages=141|issue=2|url=http://journals.iucr.org/j/issues/1981/02/00/a20480/a20480.pdf}}</ref> and related to the ] structure and can be envisaged as containing columns of octahedra sharing opposite edges and joined to other chains by corners. This contrasts with the alpha form where the octahedra are linked by adjacent edges to give zigzag chains.<ref name=j1 /> |
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The stoichiometry of the end product can be controlled by changing the temperature – for example, in the above reaction, the first step occurs at 290 °C, second at 350 °C, third at 375 °C and fourth at 600 °C. In addition, Pb<sub>2</sub>O<sub>3</sub> can be obtained by decomposing PbO<sub>2</sub> at 580–620 °C under oxygen pressure of 1.4 kbar. Therefore, thermal decomposition of lead dioxide is a common industrial way of producing various lead oxides.<ref name=g/> |
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===Chemical=== |
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===Chemical=== |
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Lead dioxide decomposes upon heating in air as follows: |
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Lead dioxide is an ] compound with prevalent acidic properties. It dissolves in strong bases to form the hydroxy] ion, Pb(OH)<sub>6</sub><sup>2−</sup>:<ref name=en/> |
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:{{chem2|24 PbO2 → 2 Pb12O19 + 5 O2}} |
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:PbO<sub>2</sub> + 2 NaOH + 2 H<sub>2</sub>O → Na<sub>2</sub> |
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:{{chem2|Pb12O19 → Pb12O17 + O2}} |
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:{{chem2|2 Pb12O17 → 8 ] + O2}} |
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:{{chem2|2 Pb3O4 → 6 ] + O2}} |
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The stoichiometry of the end product can be controlled by changing the temperature – for example, in the above reaction, the first step occurs at 290 °C, second at 350 °C, third at 375 °C and fourth at 600 °C. In addition, {{chem2|Pb2O3}} can be obtained by decomposing {{chem2|PbO2}} at 580–620 °C under an oxygen pressure of {{cvt|1400|atm|MPa}}. Therefore, thermal decomposition of lead dioxide is a common way of producing various lead oxides.<ref name=g/> |
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It also reacts with basic oxides in the melt yielding orthoplumbates M<sub>4</sub>. |
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Lead dioxide is an ] compound with prevalent acidic properties. It dissolves in strong bases to form the hydroxy] ion, {{chem2|(2−)}}:<ref name=en/> |
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Because of the instability of its Pb<sup>4+</sup> cation, lead dioxide reacts with warm acids, converting to the more stable Pb<sup>2+</sup> state and liberating oxygen:<ref name=g/> |
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:{{chem2|PbO2 + 2 NaOH + 2 H2O → Na2}} |
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:2 PbO<sub>2</sub> + 2 H<sub>2</sub>SO<sub>4</sub> → 2 PbSO<sub>4</sub> + H<sub>2</sub>O + O<sub>2</sub> |
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:2 PbO<sub>2</sub> + 4 HNO<sub>3</sub> → 2 Pb(NO<sub>3</sub>)<sub>2</sub> + H<sub>2</sub>O + O<sub>2</sub> |
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:PbO<sub>2</sub> + 4 HCl → PbCl<sub>2</sub> + 2 H<sub>2</sub>O + Cl<sub>2</sub> |
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It also reacts with basic oxides in the melt, yielding ]s {{chem2|M4}}. |
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Lead dioxide is well known for being a good oxidizing agent with example reaction listed below:<ref>{{cite book|url=http://books.google.com/?id=PpTi_JAx7PgC&pg=PA387|page=387|title=A Text Book of Inorganic Chemistry|author=Anil Kumar De|publisher=New Age International|year=2007|isbn=8122413846}}</ref> |
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:2 MnSO<sub>4</sub> + 5 PbO<sub>2</sub> + 6 HNO<sub>3</sub> → 2 HMnO<sub>4</sub> + 2 PbSO<sub>4</sub> + 3 Pb(NO<sub>3</sub>)<sub>2</sub> + 2 H<sub>2</sub>O |
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Because of the instability of its {{chem2|Pb(4+)}} cation, lead dioxide reacts with hot acids, converting to the more stable {{chem2|Pb(2+)}} state and liberating oxygen:<ref name=g/> |
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:2 Cr(OH)<sub>3</sub> + 10 KOH + 3 PbO<sub>2</sub> → 2 K<sub>2</sub>CrO<sub>4</sub> + 3 K<sub>2</sub>PbO<sub>2</sub> + 8 H<sub>2</sub>O |
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:{{chem2|2 PbO2 + 2 ] → 2 ] + 2 H2O + O2}} |
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:{{chem2|2 PbO2 + 4 ] → 2 ] + 2 H2O + O2}} |
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:{{chem2|PbO2 + 4 ] → ] + 2 H2O + Cl2}} |
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However these reactions are slow. |
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Lead dioxide is well known for being a good ], with an example reactions listed below:<ref>{{cite book|url=https://books.google.com/books?id=PpTi_JAx7PgC&pg=PA387|page=387|title=A Textbook of Inorganic Chemistry|first=Anil |last=Kumar De|publisher=New Age International|year=2007|isbn=978-81-224-1384-7}}</ref> |
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:{{chem2|2 ] + 5 PbO2 + 6 ] → 2 ] + 2 ] + 3 ] + 2 H2O}} |
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:{{chem2|2 ] + 10 ] + 3 PbO2 → 2 ] + 3 K2] + 8 H2O}} |
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===Electrochemical=== |
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===Electrochemical=== |
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Although the formula of lead dioxide is nominally given as PbO<sub>2</sub>, the actual oxygen to lead ratio varies between 1.90 and 1.98 depending on the preparation method. Deficiency of oxygen (or excess of lead) results in the characteristic metallic conductivity of lead dioxide, which can be as low as 10<sup>–4</sup> Ohm·cm and which is exploited in various electrochemical applications. Like metals, lead dioxide has a characteristic electrode potential, and in ]s it can be polarized both ] and ]. Lead dioxide electrodes have a dual action, that is both the lead and oxygen ions take part in the electrochemical reactions.<ref name=b1>{{cite book|url=http://books.google.com/?id=_PGzaO48Rz0C&pg=PA184|pages=184 ff.|title=Electrochemical power sources: primary and secondary batteries|author= M. Barak|publisher=IET|year=1980|isbn=0906048265}}</ref> |
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Although the formula of lead dioxide is nominally given as {{chem2|PbO2}}, the actual oxygen to lead ratio varies between 1.90 and 1.98 depending on the preparation method. Deficiency of oxygen (or excess of lead) results in the characteristic metallic ] of lead dioxide, with a ] as low as 10<sup>−4</sup> Ω·cm and which is exploited in various electrochemical applications. Like metals, lead dioxide has a characteristic ], and in ]s it can be polarized both ] and ]. Lead dioxide electrodes have a dual action, that is both the lead and oxygen ions take part in the electrochemical reactions.<ref name=b1>{{cite book|url=https://books.google.com/books?id=_PGzaO48Rz0C&pg=PA184|pages=184 ff|title=Electrochemical power sources: primary and secondary batteries|first= M.|last= Barak|publisher=IET|year=1980|isbn=978-0-906048-26-9}}</ref> |
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==Production== |
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==Production== |
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===Chemical processes=== |
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Lead dioxide is produced commercially by several methods, which include oxidation of Pb<sub>3</sub>O<sub>4</sub> in alkaline slurry in a chlorine atmosphere,<ref name=g/> reaction of lead(II) acetate with ], or reacting Pb<sub>3</sub>O<sub>4</sub> with dilute nitric acid:<ref name=en/> |
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Lead dioxide is produced commercially by several methods, which include oxidation of ] ({{chem2|Pb3O4}}) in alkaline slurry in a chlorine atmosphere,<ref name=g/> reaction of ] with "chloride of lime" (]),<ref>{{cite book|author=M. Baulder|chapter=Lead(IV) Oxide|title=Handbook of Preparative Inorganic Chemistry, 2nd Ed. |editor=G. Brauer|publisher=Academic Press|year=1963|place=NY, NY|volume=1|pages=758}}</ref><ref name="HOWI">{{cite book|last=Wiberg|first=Nils|title=Lehrbuch der Anorganischen Chemie |trans-title=Textbook of Inorganic chemistry |language=de|publisher=de Gruyter|location= Berlin|year=2007 |page = 919|isbn=978-3-11-017770-1}}</ref> The reaction of {{chem2|Pb3O4}} with ] also affords the dioxide:<ref name=en/><ref>{{cite book|first=Arthur|last= Sutcliffe |date=1930 |title=Practical Chemistry for Advanced Students |edition=1949 |publisher=John Murray |location=London}}</ref> |
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:Pb<sub>3</sub>O<sub>4</sub> + 4 HNO<sub>3</sub> → PbO<sub>2</sub> + 2 Pb(NO<sub>3</sub>)<sub>2</sub> + 2 H<sub>2</sub>O |
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:{{chem2|Pb3O4 + 4 HNO3 → PbO2 + 2 Pb(NO3)2 + 2 H2O}} |
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{{chem2|PbO2}} reacts with ] to form the hexahydroxoplumbate(IV) ion {{chem2|(2−)}}, soluble in water. |
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An alternative synthesis method is ]: lead dioxide forms on pure lead, in dilute ], when polarized anodically at electrode potential about +1.5 V at room temperature. This procedure is used for large-scale industrial production of PbO<sub>2</sub> anodes. Lead and ] electrodes are immersed in sulfuric acid flowing at a rate of 5–10 L/min. The electrodeposition is carried out ]ically, by applying a current of about 100 A/m<sup>2</sup> for about 30 minutes. The drawback of the lead electrode is its softness, especially compared to the hard and brittle PbO<sub>2</sub> which has a ] of 5.5.<ref name=mindat></ref> This mismatch in mechanical properties results in peeling of the coating. Therefore, an alternative method is to use harder substrates, such as ], ], ] or ] and electrodeposit PbO<sub>2</sub> on them from ] in static or flowing sulfuric acid. The substrate is usually ] before the deposition to remove surface oxide and contamination and to increase the surface roughness and adhesion of the coating.<ref name=el>{{cite book|url=http://books.google.com/?id=ArsfQZig_9AC&pg=PA573|page=573|title=Materials Handbook: A Concise Desktop Reference|author=François Cardarelli|publisher=Springer|year=2008|isbn=1846286689}}</ref> |
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===Electrolysis=== |
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An alternative synthesis method is ]: lead dioxide forms on pure lead, in dilute ], when polarized anodically at electrode potential about +1.5 V at room temperature. This procedure is used for large-scale industrial production of {{chem2|PbO2}} anodes. Lead and ] electrodes are immersed in sulfuric acid flowing at a rate of 5–10 L/min. The electrodeposition is carried out ]ically, by applying a current of about 100 A/m<sup>2</sup> for about 30 minutes. |
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The drawback of this method for the production of lead dioxide anodes is its softness, especially compared to the hard and brittle {{chem2|PbO2}} which has a ] of 5.5.<ref name=mindat>{{cite web|url=http://www.mindat.org/min-3237.html|title=Plattnerite: Plattnerite mineral information and data.|website=www.mindat.org|access-date=12 April 2018}}</ref> This mismatch in mechanical properties results in peeling of the coating which is preferred for bulk {{chem2|PbO2}} production. Therefore, an alternative method is to use harder substrates, such as ], ], ] or ] and deposit {{chem2|PbO2}} onto them from ] in static or flowing nitric acid. The substrate is usually ] before the deposition to remove surface oxide and contamination and to increase the surface roughness and adhesion of the coating.<ref name=el>{{cite book|url=https://books.google.com/books?id=ArsfQZig_9AC&pg=PA573|page=574|title=Materials Handbook: A Concise Desktop Reference|author=François Cardarelli|publisher=Springer|year=2008|isbn=978-1-84628-668-1}}</ref> |
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==Applications== |
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==Applications== |
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Lead dioxide is used in the production of ]es, pyrotechnics, dyes and the curing of ] ]s. It is also used in the construction of high-voltage ]s.<ref name=g>{{Greenwood&Earnshaw2nd|page=386}}</ref> |
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Lead dioxide is used in the production of ]es, ]s, ]s and the curing of ] ]s. It is also used in the construction of high-voltage ]s.<ref name=g>{{Greenwood&Earnshaw2nd|page=386}}</ref> |
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Lead dioxide is used as anode material in electrochemistry. Beta-PbO<sub>2</sub> is more attractive for this purpose than the alpha form because it has relatively low resistivity, good corrosion resistance even in low-pH medium, and a high ] for the evolution of oxygen in sulfuric acid and nitric acid based electrolytes. Lead dioxide can also withstand chlorine evolution in ]. Lead dioxide anodes are inexpensive and were once used instead of conventional platinum and graphite electrodes for regenerating ]. They were also applied as oxygen anodes for ] copper and zinc in sulfate baths. In organic synthesis, lead dioxide anodes were applied for the production of ] from ] in a sulfuric acid electrolyte.<ref name=el/> |
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Lead dioxide is used as an ] material in electrochemistry. β-{{chem2|PbO2}} is more attractive for this purpose than the α form because it has relatively low ], good ] resistance even in low-] medium, and a high ] for the evolution of oxygen in sulfuric- and nitric-acid-based electrolytes. Lead dioxide can also withstand ] evolution in ]. Lead dioxide anodes are inexpensive and were once used instead of conventional ] and ] electrodes for regenerating ]. They were also applied as oxygen anodes for ] ] and ] in sulfate baths. In organic synthesis, lead dioxide anodes were applied for the production of ] from ] in a sulfuric acid electrolyte.<ref name=el/> |
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=== Lead acid battery === |
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The most important use of lead dioxide is as the cathode of ]. Its utility arises from the anomalous metallic conductivity of PbO<sub>2</sub>. The ] battery stores and releases energy by shifting the equilibrium (a comproportionation) between metallic lead, lead dioxide, and lead(II) salts in ]. |
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The most important use of lead dioxide is as the cathode of ]. Its utility arises from the anomalous metallic conductivity of {{chem2|PbO2}}. The ] battery stores and releases energy by shifting the equilibrium (a comproportionation) between metallic lead, lead dioxide, and lead(II) salts in ]. |
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:Pb + PbO<sub>2</sub> + 2 HSO<sub>4</sub><sup>−</sup> + 2 H<sup>+</sup> → 2 PbSO<sub>4</sub> + 2 H<sub>2</sub>O, E = +2.05 V |
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:{{chem2|Pb + PbO2 + 2 HSO4− + 2 H+ → 2 PbSO4 + 2 H2O}} {{pad|5em}} ''E''° = +2.05 V |
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==Safety== |
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==Safety== |
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Lead compounds are ]. Chronic contact with the skin can potentially cause lead poisoning through absorption, or redness and irritation in the short term.<ref>{{cite web|url=http://hazard.com/msds/mf/baker/baker/files/l2956.htm|title=LEAD DIOXIDE|website=hazard.com|url-status=usurped|archive-url=https://web.archive.org/web/20210413141423/http://hazard.com/msds/mf/baker/baker/files/l2956.htm|archive-date=13 April 2021|access-date=12 April 2018}}</ref> |
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Being a strong oxidant, lead dioxide is a poison when ingested. The associated symptoms include abdominal pain and spasms, nausea, vomiting and headache. Acute poisoning can lead to muscle weakness, metallic taste, loss of appetite, insomnia, dizziness, with shock, coma and death in extreme cases. The poisoning also results in high lead levels in blood and urine. Contact with skin or eyes results in local irritation and pain.<ref></ref> |
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{{chem2|PbO2}} is not combustible, but it enhances flammability of other substances and the intensity of the fire. In case of a fire it gives off irritating and toxic fumes.<ref name=nih>{{Cite web |last=PubChem |title=Lead dioxide |url=https://pubchem.ncbi.nlm.nih.gov/compound/14793 |access-date=2022-12-15 |website=pubchem.ncbi.nlm.nih.gov |language=en}}</ref>{{better citation needed|reason=90% of the info in the pubchem reference is either generic information about oxidizers or specific to ammonium nitrate for some unknown reason that's probably a database error.|date=September 2024}} |
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Lead dioxide is poisonous to aquatic life, but because of its insolubility it usually settles out of water.<ref>{{cite web|url=https://www.ltschem.com/msds/PbO2.pdf|title=Product and Company Identification|website=ltschem.com|access-date=29 February 2024}}</ref><ref name="nih" /> |
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==References== |
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==References== |
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{{reflist|30em}} |
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==External links== |
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==External links== |
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{{Lead compounds}} |
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{{Lead compounds}} |
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{{Oxides}} |
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