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1 REAZIONI DI IDENTIFICAZIONE DI CATIONI DI INTERESSE FARMACEUTICO E TOSSICOLOGICO •Argento •Mercurio •Piombo •Bismuto •Rame •Arsenico •Antimonio •Alluminio •Ferro •Zinco •Manganese •Cobalto •Calcio •Bario •Magnesio •Litio •Sodio •Potassio •Ammonio

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11

REAZIONI DI IDENTIFICAZIONE DI CATIONI DI INTERESSE FARMACEUTICO E

TOSSICOLOGICO

•Argento

•Mercurio

•Piombo

•Bismuto

•Rame

•Arsenico

•Antimonio

•Alluminio

•Ferro

•Zinco

•Manganese

•Cobalto

•Calcio

•Bario

•Magnesio

•Litio

•Sodio

•Potassio

•Ammonio

2

ARGENTOARGENTOn.o. = 0, +1Metallo nobile, solubile in acidi ossidanti.

SILVER (Eu Ph)

Dissolve about 10 mg of the substance to be examined in 10 ml of water R or use 10 ml of the prescribed solution. Add 0.3 ml of hydrochloric acid R1. A curdled, white white precipitateprecipitate is formed that dissolves on addition of 3 ml of dilute ammonia R1.

Ag+ + Cl - AgCl

AgCl + 2NH3 [Ag(NH3)2] + + Cl-

[Ag(NH3)2] + + Cl- + 2H+ AgCl + 2NH4+

Composti di interesse farmaceutico

AgNO3

Ag-proteinato (FU), Silver, colloidal, for external use (Eu Ph)

Attività farmacologica e tossicologica: Antisettico Intossicazione cronica: argirismoIntossicazione acuta: vomito, dolori addominali, collasso

33

MERCURIOMERCURIOn.o. = 0, +1 (+Hg-Hg+), +2Solubile in acidi ossidanti. Liquido (d = 13.6).

MERCURY (Eh Ph)

b) To the prescribed solution add dilute sodium hydroxide solution R until strongly alkaline (2.2.4). A dense yellowdense yellow precipitate is formed (mercuric salts). 

Hg 2+ + 2OH- HgO + H2O

Stannoso cloruro

2Hg 2+ + Sn2+ + 2Cl- Hg2Cl2 + Sn 4+

Hg2Cl2 + Sn2+ 2Hg + Sn4+ + 2 Cl-   

Potassio ioduro

Hg 2+ + 2I- HgI2

HgI2 + 2I- [HgI4]2-

44

Sodio solfuro

Hg 2+ + S 2- HgS

3 HgS + 2 NO3-+ 12 Cl- + 8 H+ 3 [HgCl4] 2- + 3 S + 2NO + 4 H2O

Composti di interesse farmaceuticoHgCl2

HgO (FU)

Attività farmacologica e tossicologica AntisetticoElemento stimolatorio. Teratogeno. 

Intossicazione cronica: idrargirismo (insonnia, tremori, degenerazione e necrosi dei tubuli renali e delle mucose)

55

Chelanti nelle intossicazioni da mercurio e piomboChelanti nelle intossicazioni da mercurio e piombo

Vie di somministrazione

intramuscolare orale orale

66

LEAD (Eu Ph)

a) Dissolve 0.1 g of the substance to be examined in 1 ml of acetic acid R or use 1 ml of the prescribed solution. Add 2 ml of potassium chromate solution R. A yellow yellow precipitateprecipitate is formed that dissolves on addition of 2 ml of strong sodium hydroxide solution R.

PIOMBOPIOMBOn.o. = 0, +2, +4Solubile in acido nitrico, subisce passivazione in acido cloridrico e solforico.

Pb 2+ + CrO42- PbCrO4

PbCrO4 + 4OH- [Pb(OH)4] 2- + CrO4 2-

2 PbCrO4 + 2H+ 2Pb 2+ + Cr2O7 2- + H2O

b) Dissolve 50 mg of the substance to be examined in 1 ml of acetic acid R or use 1 ml of the prescribed solution. Add 10 ml of water R and 0.2 ml of potassium iodide solution R. A yellow precipitateyellow precipitate is formed. Heat to boiling for 1 min to 2 min. The precipitate dissolves. Allow to cool. The precipitate is re-formed as glistening, yellow plates.

Pb 2+ + 2I - PbI2

PbI2 + 2I - [PbI4]2-

77

 Acido cloridrico

Pb 2+ + 2Cl - PbCl2

 sodio solfuro

Pb 2+ + S 2- PbS

3 PbS + 2 NO3- + 8 H+ 3 Pb 2+ + 3 S + 2 NO + 4 H2O

 

Composti di interesse farmaceutico

Nessuno nella FU XII

 

Attività farmacologica e tossicologica

Elemento stimolatorio. Cancerogeno e teratogeno.

 

Intossicazione cronica: saturnismo

88

 BISMUTH (Eu Ph)

a) To 0.5 g of the substance to be examined add 10 ml of dilute hydrochloric acid R or use 10 ml of the prescribed solution. Heat to boiling for 1 min. Cool and filter if necessary. To 1 ml of the solution obtained add 20 ml of water R. A whitewhite or slightly yellow precipitate is formed which on addition of 0.05 ml to 0.1 ml of sodium sulphide solution R turns brownbrown.

H2N

H2NC S Bi+3 + 2 S C

NH2

NH2

Bi+3 C SH2N

H2N

BISMUTOBISMUTOn.o. = 0, +3, +5Solubile in acidi ossidanti.

Bi3+ + Cl- + H2O BiOCl + 2H+

2 Bi 3+ + 3 S 2- Bi2S3

b) To about 45 mg of the substance to be examined add 10 ml of dilute nitric acid R or use 10 ml of the prescribed solution. Boil for 1 min. Allow to cool and filter if necessary. To 5 ml of the solution obtained add 2 ml of a 100 g/l solution of thiourea R. A yellowish-yellowish-orangeorange colour or an orange precipitate is formed.

99

2 Bi 3+ + 3 S 2- Bi2S3

Bi2S3 + 2 NO3 - + 8 H+ 2 Bi3+ + 2 NO + 3 S + 4 H2O

Composti di interesse farmaceutico

Bismuth subcarbonate

Bismuto nitrato basico, Bismuth subnitrate : 4[BiNO3(OH)2].BiO(OH)

 

Attività farmacologica e tossicologica

Antisettico. Antiacido e protettivo gastrico.

 

Intossicazione cronica: effetti simili al saturnismo

 

 

1010

A. Cu 2+ + 2 OH- Cu(OH)2

Cu 2+ + 4NH3 [Cu(NH3)4] 2+

Sodio solfuro

Cu 2+ + S 2- CuS

3 CuS + 2 NO3- + 8 H+ 3 Cu 2+ + 3 S + 2 NO + 4 H2O

COPPER SULPHATE, ANHYDROUSIDENTIFICATION

A.  Add several drops of dilute ammonia R2 to 1 ml of solution S (see Tests). A blue blue precipitateprecipitate is formed. On further addition of dilute ammonia R2 the precipitate dissolves and a dark blue colourdark blue colour is produced.

B.  Loss on drying (see Tests).C.  Dilute 1 ml of solution S to 5 ml with water R. The solution gives reaction (a) of

sulphates (2.3.1).

RAMERAMEn.o. = 0, +1, +2Solubile in acidi ossidanti.

1111

Potassio ferrocianuro2K+ + Cu 2+ + [Fe(CN)6 ]4- CuK2 [Fe(CN)6] rosso brunorosso bruno

Composti di interesse farmaceuticoCuSO4 (anidro e pentaidrato)

Attività farmacologica e tossicologicaOligoelemento essenziale. Stimolatorio. Antisettico, spermicida e astringente. Emetico.

Eu Ph (homoeopathic preparations)Copper acetate monohydrate for homoeopathic preparations

Copper for homoeopathic preparations

IDENTIFICATION

A. To 2 ml of solution S (see Tests) add 0.5 ml of potassium ferrocyanide solution R. A reddish-brownreddish-brown precipitate is formed.

B. To 5 ml of solution S add 0.6 ml of ammonia R. A blue precipitateblue precipitate is formed. Add 2 ml of ammonia R. The precipitate disappears; the solution has an intense blue colourblue colour . TESTSSolution S. Dissolve 2.0 g in 10 ml of nitric acid R. After nitrous fumes are no longer evolved, dilute to 60 ml with distilled water R.

1212

ARSENIC (Eu Ph)

Heat 5 ml of the prescribed solution on a water-bath with an equal volume of hypophosphorous reagent R. A brown precipitatebrown precipitate is formed.

Reattivo ipofosforoso (Bougault-Engel) in HCl conc

4As 3+ + 3H2PO2 - + 6H2O 4As + 3H2PO4- + 12H+

Sodio solfuro

2As 3+ + 3S 2- As2S3 giallogiallo

As2S3 + 3 S 2- 2 AsS3 3-

As2S3 + 6 OH- AsS3 3- + AsO3 3- + 3 H2O

3 As2S3 + 10 NO3- + 10 H+ + 4 H2O 6 H3AsO4 + 10 NO + 9 S

ARSENICOARSENICOn.o. = 0, -3, +3, +5Solubile in acidi ossidanti.

1313

Eu Ph (homoeopathic preparations)

Arsenious trioxide

A. Dissolve 20 mg in 1 ml of dilute hydrochloric acid R, add 4 ml of water R and 0.1 ml of sodium sulphide solution R. The resulting yellow precipitateyellow precipitate is soluble in dilute ammonia R1.

B. Dissolve 20 mg in 1 ml of hydrochloric acid R1, add 5 ml of hypophosphorous reagent R and heat for 15 min on a water-bath. A blackblack precipitate develops.

Composti di interesse farmaceuticoAs2O3 (nella terapia omeopatica)

 Attività farmacologica e tossicologicaStimolatorio. Tonico e ricostituente.Cancerogeno (As3+, As5+) e teratogeno (As5+) 

1414

ANTIMONY (Eu Ph)

Dissolve with gentle heating about 10 mg of the substance to be examined in a solution of 0.5 g of sodium potassium tartrate R in 10 ml of water R and allow to cool: to 2 ml of this solution, or to 2 ml of the prescribed solution, add sodium sulphide solution R dropwise; an orange-redorange-red precipitate is formed which dissolves on addition of dilute sodium hydroxide solution R.

2 Sb 3+ + 3S 2- Sb2S3

Sb2S3 + 3S 2- 2SbS3 3-

Sb2S3 + 6OH - SbO33- + SbS3

3- + 3H2O

Sb2S3 + 6H+ + 8Cl- 2 [SbCl4] - + 3H2S

Composti di interesse farmaceuticoNessuno nella FU Attività farmacologica e tossicologicaStimolatorio

ANTIMONIOANTIMONIOn.o. = 0, -3, +3, +5Solubile in acqua regia a causa di passivazione.

1515

ALUMINIUM (Eu Ph)

Dissolve about 15 mg of the substance to be examined in 2 ml of water R or use 2 ml of the prescribed solution. Add about 0.5 ml of dilute hydrochloric acid R and about 0.5 ml of thioacetamide reagent R. No precipitate is formed. Add dropwise dilute sodium hydroxide solution R. A gelatinous white precipitategelatinous white precipitate is formed which dissolves on further addition of dilute sodium hydroxide solution R. Gradually add ammonium chloride solution R. The gelatinous white precipitate is re-formedwhite precipitate is re-formed.

Al 3+ + 3OH- Al(OH)3

Al(OH)3 + OH- [Al(OH)4]-

[Al(OH)4]- + NH4+ Al(OH)3 + NH3 + H2O

Composti di interesse farmaceutico

Allume (AlK(SO4)2.12H2O), AlCl3.6H2O, AlPO4, Al2(SO4)3.nH2O, [AlO(OH)]nH2O, alluminio magnesio silicato, alluminio ossido idrato, alluminio sodio silicato.

 Attività farmacologica e tossicologica

Astringente, antisettico e emostatico, antiacido e adsorbente.

ALLUMINIOALLUMINIOn.o. = 0, +3Solubile in acqua (passivazione), acidi e basi.

1616

Dal prodotto di solubilita si ha: Per:

[Al(OH)4]- + H+ Al(OH)3 + H2O

1717

IRON (Eu Ph)

a) Dissolve a quantity of the substance to be examined equivalent to about 10 mg of iron (Fe2+ ) in 1 ml of water R or use 1 ml of the prescribed solution. Add 1 ml of potassium ferricyanide solution R. A blueblue precipitate is formed that does not dissolve on addition of 5 ml of dilute hydrochloric acid R.

FERROFERROn.o. = 0, +2, +3Solubile in acidi.

Fe2+ + K+ + [Fe(CN)6]3- KFe[Fe(CN)6

b) Dissolve a quantity of the substance to be examined equivalent to about 1 mg of iron (Fe3+ ) in 30 ml of water R. To 3 ml of this solution or to 3 ml of the prescribed solution, add 1 ml of dilute hydrochloric acid R and 1 ml of potassium thiocyanate solution R. The solution is coloured redred.

Fe3+ + SCN- [Fe(SCN)]2+

c) Dissolve a quantity of the substance to be examined equivalent to not less than 1 mg of iron (Fe3+ ) in 1 ml of water R or use 1 ml of the prescribed solution. Add 1 ml of potassium ferrocyanide solution R. A blueblue precipitate is formed that does not dissolve on addition of 5 ml of dilute hydrochloric acid R.

Fe3+ + K+ + [Fe(CN)6]4- KFe[Fe(CN)6

1818

Sodio idrossido

Fe 2+

Fe2+ + 2OH- Fe(OH)2 verdeverde

4Fe(OH)2 + O2 + 2H2O 4Fe(OH)3 rosso-brunorosso-bruno

Fe 3+

Fe3+ + 3OH- Fe(OH)3

Composti di interesse farmaceutico

FeCl3.6H2O, FeSO4.7H2O

Ferro ossido giallo FeO(OH) (FU), ferro ossido rosso Fe2O3 (FU)

Attività farmacologica e tossicologicaOligoelemento essenziale. Ferro (II) è antianemico. Fe (III) favorisce la coagulazione del sangue.

1919

Zn2+ + 2OH- Zn (OH) 2 + 2OH- [Zn (OH)4] 2-

[Zn (OH)4 ]2- + S2- ZnS + 4 OH-

Zn2+ + S2- ZnS

Potassio ferrocianuro

3Zn2+ + 2K+ + 2[Fe(CN)6]4- K2Zn3 [Fe(CN)6]2

Composti di interesse farmaceutico

ZnCl2, ZnO, ZnSO4(7H2O, 6H2O, H2O), zinco acetato

Attività farmacologica e tossicologicaOligoelemento essenziale. Stimolatorio. Antisettico.Cancerogeno e teratogeno.

ZINC (Eu Ph)

Dissolve 0.1 g of the substance to be examined in 5 ml of water R or use 5 ml of the prescribed solution. Add 0.2 ml of strong sodium hydroxide solution R. A white precipitatewhite precipitate is formed. Add a further 2 ml of strong sodium hydroxide solution R. The precipitate dissolves. Add 10 ml of ammonium chloride solution R. The solution remains clear. Add 0.1 ml of sodium sulphide solution R. A flocculent white precipitatewhite precipitate is formed.

ZINCOZINCOn.o. = 0, +2Solubile in acidi e basi. In acqua subisce passivazione.

2020

4 MnO4- + CH3CH2OH + 4 OH- 4 MnO4

2- + CH3COOH + 3 H2O

2 MnO42- + 2 H2O 2 MnO2 + 4 OH- + O2

Mn2+

Sodio idrossidoMn2+ + 2OH- Mn(OH)2

2Mn(OH)2 + O2 2MnO2 + 2H2O

MnO2 + Mn(OH)2 Mn2O3 + H2O

Potassium permanganate KMnO4

IDENTIFICATION

A. Dissolve about 50 mg in 5 ml of water R and add 1 ml of ethanol (96 per cent) R and 0.3 ml of dilute sodium hydroxide solution R. A greengreen colour develops. Heat to boiling. A dark browndark brown precipitate is formed.

MANGANESEMANGANESEn.o. = 0, +2 (Mn2+), (+3), +4 (MnO2), (+5), +6 (MnO4

2-), +7 (MnO4-)

Solubile in acidi.

2121

Sodio solfuro (pH 9)

Mn2+ + S2- MnS

MnS + 2H+ Mn2+ + H2S

Piombo diossido in ambiente acido (HNO3)

2 Mn2+ + 5 PbO2 + 4 H+ 2 MnO4- + 5 Pb2+ + 2 H2O

ione permanganato-colore violaione permanganato-colore viola

2MnO4- + 3Mn2+ +2H2O 5MnO2 + 4H+

Composti di interesse farmaceutico

KMnO4

Attività farmacologica e tossicologicaMicroelemento essenziale. Intossicazione cronica: manganismo.

2222

COBALTOCOBALTOn.o. = 0, +2, +3Solubile in acidi

Sodio idrossidoCo2+ + 2OH- Co(OH)Co(OH)22

4Co(OH)2 + O2 + 2H2O 4Co(OH)3  Sodio solfuro (pH 9)2Co(NH3)63+ + 3S 2- 2 CoS + S + 12NH3

4CoS + O2 + 2H2O 4  

Potassio nitrito in ambiente aceticoCo2+ + 7NO2

- + 3K+ + 2H+ KK33[Co(NO[Co(NO22))66]] + NO + H2O

Ammonio solfocianuro Co2+ + 4SCN- [Co(SCN)[Co(SCN)44]]2-2-

Composti di interesse farmaceutico Nessuno

Attività farmacologica e tossicologica Microelemento essenziale.

Co O H

S

2323

CALCIUM (Eu Ph)

b) Dissolve about 20 mg of the substance to be examined or the prescribed quantity in 5 ml of acetic acid R. Add 0.5 ml of potassium ferrocyanide solution R. The solution remains clear. Add about 50 mg of ammonium chloride R. A whitewhite, crystalline precipitate is formed.

Ca2+ + K+ + NH4+ + [Fe(CN)6] 4- CaKNH4[Fe(CN)6]

Ammonio ossalato (pH 5)

Ca2+ + C2O42- CaC2O4

 

Composti di interesse farmaceutico

CaCO3, CaCl2 (2H2O, 6H2O), CaHPO4, Ca(OH)2, CaSO4.2H2O, calcio fosfato

Attività farmacologica e tossicologicaElemento essenziale.

CALCIOCALCIOn.o. = 0, +2Solubile in acidi ed in acqua (passivazione).

2424

Barium sulphateBarii sulfas

BaSO4 Mr 233.4[7727-43-7]

CHARACTERSAppearance: fine, white or almost white powder, free from gritty particles. Solubility: practically insoluble in water and in organic solvents. It is very slightly soluble

in acids and in solutions of alkali hydroxides.

IDENTIFICATION

A.  Boil a suspension of 0.2 g with 5 ml of a 500 g/l solution of sodium carbonate R for 5 min, add 10 ml of water R, filter and acidify a part of the filtrate with dilute hydrochloric acid R. The solution gives the reactions of sulphates (2.3.1).

B.  Wash the residue collected in the preceding test with 3 successive small quantities of water R. To the residue add 5 ml of dilute hydrochloric acid R, filter and add to the filtrate 0.3 ml of dilute sulphuric acid R. A whitewhite precipitate is formed that is insoluble in dilute sodium hydroxide solution R.

A. BaSO4 + CO32- BaCO3 + SO4

2-

SO42- + Ba 2+ BaSO4

B. BaCO3 + 2 H+ Ba 2+ + CO2 + H2O

Ba 2+ + SO42- BaSO4

BARIOBARIO

2525

MAGNESIUM (Eu Ph)

Dissolve about 15 mg of the substance to be examined in 2 ml of water R or use 2 ml of the prescribed solution. Add 1 ml of dilute ammonia R1. A white precipitate is formed that dissolves on addition of 1 ml of ammonium chloride solution R. Add 1 ml of disodium hydrogen phosphate solution R. A whitewhite crystalline precipitate crystalline precipitate is formed.Mg2+ + 2 OH- Mg(OH)2

NH4+ + OH- NH3 + H2O

Mg2+ + HPO42- + NH3 MgNH4PO4

Sodio idrossido + magnesone II

Mg 2+ + 2 OH- Mg(OH)Mg(OH)22 adsorbe magnesoneadsorbe magnesone

Composti di interesse farmaceutico

MgO, MgCl2.6H2O, Mg-acetato.4H2O, Mg(OH)2, MgSO4.7H2O, Mg-carbonato, Mg-trisilicato

Attività farmacologica e tossicologicaElemento oligoessenziale. Lassativo e/o purgante. Antiacido.

MAGNESIOMAGNESIOn.o. = 0, +2Solubile in acidi ed in acqua

26

LITIOLITIOn.o. = 0, +1 - Solubile in acqua con reazione fortemente esotermica.

Lithium carbonateLithium carbonateLithii carbonas

Li2CO3 Mr 73.9[554-13-2]DEFINITIONContent: 98.5 per cent to 100.5 per cent.CHARACTERS

Appearance: white ►or almost white◄ powder. Solubility: slightly soluble in water, practically insoluble in ethanol (96 per cent).

IDENTIFICATIONA. When moistened with hydrochloric acid R, it gives a red colourred colour to a non-luminous flame.C. It gives the reaction of carbonates (2.3.1).

Sodio fosfato bibasico

3Li+ + OH – + HPO42- Li3PO4 + H2O

Composti di interesse farmaceuticoLi2CO3: psicofarmaco

Attività farmacologica e tossicologicaElemento stimolatorio e ultratraccia essenziale. Teratogeno.

2727

SODIOSODIOn.o. = 0, +1Solubile in acqua con reazione fortemente esotermica.

SODIUM (Eu Ph)

a) Dissolve 0.1 g of the substance to be examined in 2 ml of water R or use 2 ml of the prescribed solution. Add 2 ml of a 150 g/l solution of potassium carbonate R and heat to boiling. No precipitate is formed. Add 4 ml of potassium pyroantimonate solution R and heat to boiling. Allow to cool in iced water and if necessary rub the inside of the test-tube with a glass rod. A dense white precipitatedense white precipitate is formed.

H2Sb2O7 2- + 5H2O 2[Sb(OH)6]-

Na+ + [Sb(OH)6]- Na[Sb(OH)6

Composti di interesse farmaceutico

NaCl, NaBr, NaI, Na-acetato.3H2O, Na3citrato, NaH2PO4, Na2SO4.10H2O, NaHCO3, Na2CO3, NaBO3.4H2O

Attività farmacologica e tossicologica

Elemento essenziale.

2828

POTASSIOPOTASSIOn.o. = 0, +1Solubile in acqua con reazione fortemente esotermica.

POTASSIUM

a) Dissolve 0.1 g of the substance to be examined in 2 ml of water R or use 2 ml of the prescribed solution. Add 1 ml of sodium carbonate solution R and heat. No precipitate is formed. Add to the hot solution 0.05 ml of sodium sulphide solution R. No precipitate is formed. Cool in iced water and add 2 ml of a 150 g/l solution of tartaric acid R. Allow to stand. A white crystallinewhite crystalline precipitate is formed.

K+ + HOOC-(CHOH)2-COOH HOOC-(CHOH)2-COOK + H+

b) Dissolve about 40 mg of the substance to be examined in 1 ml of water R or use 1 ml of the prescribed solution. Add 1 ml of dilute acetic acid R and 1 ml of a freshly prepared 100 g/l solution of sodium cobaltinitrite R. A yellow or orange-yellowyellow or orange-yellow precipitate is formed immediately.

3 K+ + [Co(NO2)6]3- K3[Co(NO2)6]

Composti di interesse farmaceutico

KCl, K-acetato, K3citrato, KBr, KI, K2CO3, KHCO3, KNO3, KH2PO4, KMnO4

Attività farmacologica e tossicologica

Elemento essenziale.

2929

AMMONIOAMMONIO

AMMONIUM SALTS AND SALTS OF VOLATILE BASES

Dissolve about 20 mg of the substance to be examined in 2 ml of water R or use 2 ml of the prescribed solution. Add 2 ml of dilute sodium hydroxide solution R. On heating, the solution gives off vapour that can be identified by its odouridentified by its odour and by its alkaline reaction (2.2.4).

NH4+ + OH- NH3 + H2O

Sodio cobaltinitrito 3 NH4

+ + [Co(NO2)6]3- (NH4)3[Co(NO2)6]

Reattivo di Nessler (soluzione di potassio iodomercurato in NaOH) 

2[HgI4]2- + NH4

+ + 4OH- I + 7I- + 3 H2O colorazione giallo-aranciogiallo-arancio  Composti di interesse farmaceuticoNH3, NH4Cl, NH4Br, (NH4)HCO3

OHg

NH2

Hg