LECTURE № 2
Theme: Inorganic drugs of
Oxygen, Hydrogen,
Magnesium, Manganese,
Iodine, Sulphur and Nitrogen
with redox properties
Associate prof. Mosula L.M.
The plan
1. Inorganic drugs of Oxygen and Hydrogen: oxygen,
hydrogen peroxide, hydroperitum, magnesium peroxide.
2. Inorganic preparation of Manganese - potassium
permanganate.
3. Inorganic preparation of Magnesium - magnesium peroxide.
4. Inorganic drugs of Nitrogen: nitrous oxide, sodium nitrite.
5. Inorganic preparation of Iodine - iodine.
6. Inorganic preparations of Sulphur: sulphur for external use,
sodium thiosulphate.
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Monographs: Medicinal and Pharmaceutical Substances
SP IX
Oxygen
Oxygen
Oxygenum*
General Notices
О2
(Ph Eur monograph 0417)
32.00
Oxygen should be kept in approved metal cylinders, the shoulders of which are painted white and
the remainder black. The cylinder should carry a label stating 'Oxygen'. In addition, 'Oxygen' or the
symbol 'O2' should be stencilled in paint on the shoulder of the cylinder. When Oxygen is intended for
use in a room in which magnetic resonance imaging (MRI) is being performed, the cylinder and fittings
should be made from suitable non-ferromagnetic materials and labelled accordingly.
Ph Eur
2H2 + O2
DEFINITION
Content
Minimum 99.5 per cent V/V of O2.
This monograph applies to oxygen for medicinal use.
CHARACTERS
Appearance
Colourless, odourless gas.
Solubility
At 20 °C and at a pressure of 101 kPa, 1 volume
dissolves in about 32 volumes of water.
2KClO3 →2KCl + 3O2
PRODUCTION
Carbon dioxide
Maximum 300 ppm V/V, determined using an infrared
analyser (2.5.24).
Carbon monoxide
Maximum 5 ppm V/V, determined using an infrared
analyser (2.5.25).
Water (2.5.28)
Obtaining
1. Distillation of liquefied (condensed) air. Now oxygen to
receive from air by its liquefaction. Air contains 21 % of oxygen О2 and
79 % of nitrogen N2. At distillation of liquefied (condensed) air, at
first is distillate of nitrogen (-195,8 °С), and then - oxygen (-183 °С).
2. Electrolysis of water.
Anode: 2Н2О – 4е  4Н+ + О2
Cathode: 2Н2О + 2е 2ОН– + Н2
3. Laboratory methods (for obtaining no more quatitative
O2):
а) Thermal decomposition of potassium chlorate:
2KClO3 →2KCl + 3O2
b) Thermal decomposition of mercury(II) oxide:
2HgO → 2Hg + O2
c) Interaction peroxides with CO2:
2Na2O2 + 2CO2  2Na2CO3 + O2
IDENTIFICATION
First identification C.
Second identification A, B.
A. Place a glowing splinter of wood in the substance to be
examined. The splinter bursts into flame.
B. Shake with alkaline pyrogallol solution R. The substance to be
examined is absorbed and the solution becomes dark brown.
C. It complies with the limits of the assay.
Other reaction:
(SPU) Mix of nitrogen(II) oxide and oxygen and obtained brown
colour of gas :
2NO + O2 = 2NO2
brown gas
(Difference from nitrogen (I) oxide).
TESTS
Carbon dioxide (2.1.6) –inadmissible impurity.
Maximum 300 ppm V/V, determined using a carbon dioxide detector tube.
Or by means reaction: Ba(OH)2 + CO2 = BaCO3 + H2O
opalescence is not be
present
Carbon monoxide (2.1.6) –inadmissible impurity.
Maximum 5 ppm V/V, determined using a carbon monoxide detector tube.
Or by means reaction: СО + 2[Ag(NH3)2]NO3 + 2H2O = 2Ag +
(NH4)2CO3 + 2NH4NO3
brown colour
is
not be present
Water vapour (2.1.6)
Maximum 67 ppm V/V, determined using a water vapour detector tube.
IMPURITIES
Specified impurities A, B, C.
A. carbon dioxide,
B. carbon monoxide,
C. water.
Assay
Determine the concentration of oxygen using a paramagnetic analyser.
(Ph. Eur. method 2.5.27)
Pass the gas to be examined through the instrument at a constant flow
rate until a suitable reading is obtained.
STORAGE
As a compressed gas or liquid in appropriate containers, complying with
the legal regulations. Taps and valves are not to be greased or oiled.
Action and use
Apply at the diseases, accompanied hypoxia (oxygen depletion). In
particular, at poisonings of СО, HCN, Cl2, phosgene COCl2 and other gases use
a mix with air, containing 40-60 % of oxygen.
Use an oxygen cocktail (oxygen foam) for glaucoma treatment, and also
for improvement of exchange processes.
Widely use oxygen for so-called hyperbaric oxygenation - oxygen
application under the raised pressure (1,2 - 2 atm), in surgery (operation in
special pressure chamber), intensive therapy of heavy diseases, in
reanimotologia. Thus saturation of tissues by oxygen, the brain is protected
from hypoxia.
Carbogenum – is the gas mix, containing 95 % О2 and 5–7% СО2,
applied in anesthesiology for respiration stimulation.
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Chlorinated Lime
SP IX
Chlorinated Lime
General Notices
Calcaria chlorata
Calcii hypochloris crudus
Calcium hypochlorosum
Possible structure of Chlorinated Lime is:
OCl
3 Ca
*
Ca(OH)2 * nH2O
Cl
Chlorinated Lime is a mix of Ca(ClО)2 and CaCl2:
Ca(ClО)2CaCl2 = Ca2O2Cl4 = 2CaOCl2
Elementary formula of Chlorinated Lime is:
CaOCl2
DEFINITION
Chlorinated Lime contains not less than 30.0% w/w of available
chlorine, Cl.
OBTAINING
Heating (t  1000 C) Calcium natural minerals with
the next saturation of chlorine (Cl2):
CaCO3  CaО + CO2
CaО + H2O = Ca(OH)2 + Q
Ca(OH)2 + Cl2 = CaOCl2 + H2O
CHARACTERISTICS
A dull white powder.
Partly soluble in water and in ethanol (96%).
IDENTIFICATION
A. (BrPh, SP IX). Interaction with mineral
acids. Evolves chlorine copiously on the addition of 2M hydrochloric acid
.
CaOCl2 + HCl = CaCl2 + H2O + Cl2↑
B. (BrPh, SP IX). When shaken with water and filtered, the filtrate
yields reaction C characteristic of calcium salts and
reaction A characteristic of chlorides, Appendix VI.
Calcium and Calcium Salts:
A. (BrPh, SPU). Reaction with glyoxal-hydroxyanil
alcoholic solution in the alkaline medium.
To 0.2 ml of a neutral solution containing a quantity of the substance to be
examined equivalent to about 0.2 mg of calcium (Ca2+) per millilitre or to 0.2 ml of
the prescribed solution add 0.5 ml of a 2 g/l solution of glyoxal-hydroxyanil R in
ethanol (96 per cent) R, 0.2 ml of dilute sodium hydroxide solution R and 0.2 ml of
sodium carbonate solution R. Shake with 1 ml to 2 ml of chloroform R and add 1 ml
to 2 ml of water R. The chloroform layer is coloured red.
OH
Ca
O
O
HO
N
CH
CH
N
+ Ca
2+
N
CH
CH
N
+ 2H+
B. (BrPh, SPU). Reaction with potassium ferrocyanide solution
in the acetic-acid medium.
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 white, crystalline precipitate is formed.
Ca2+ + К + 2NH4+ + [Fe(CN)6]4– →(NH4)2КCa[Fe(CN)6]↓.
white, crystalline precipitate
CO2 + Ca(OH)2 = CaCO3 + H2O
5. Nitrates and nitrites (an inadmissible impurity). To 1 ml of
water cautiously add 1 ml fresh prepared solution of
diphenylamine; there should not be a dark blue colouring:
2
NH
H 2SO4
NH
NH
NO2, H2SO4
NH
+
NH
HSO4
H
6. Ammonia (an admissible impurity). At interaction of water of
10 ml about 0,2 ml of Несслера‘s reagent (an alkaline solution of
potassium tetraiodomercurat [K2HgI4]), the formed yellow
colouring should not be more intensive, than colouring of the
standard (etalon), containing 10 ml of 0,0002 % (0,002 mg/ml)
solution NH3):
NH4+ +HgI42- + 2OH– = [I2Hg2NH2]I + 5I– + 2H2O
In water cleared impurity NH3 in 10 times more, than at water
distilled is supposed.
7. Chlorides (an admissible impurity). At interaction with a solution
of AgNO3 at presence of HNO3, formed opalescence should not be
more intensively opalescence of a standart (reference) solution:
Cl– + Ag+
HNO
3


AgCl
8. Sulphates (an admissible impurity). At interaction of water with a
solution of barium chloride BaCl2 at presence of HCl, opalescence
should not exceed opalescence of a reference solution:
SO42– + Ba2+
HCl


BaSO4
9. Calcium (an admissible impurity). Opalescence, formed at
interaction with a solution (NH4) 2C2O4 in the presence of
solution NH3, should not be more intensively opalescence a
standart (reference) solution:
Ca2+ + C2O42– = CaC2O4
10. Heavy metals (an admissible impurity). At interaction about
sodium sulphide Na2S in the presence of acid acetic CH3COOH
and the further comparison with the standard(etalon) supposes only
light opalescence at the expense of sulphur, which is allocated from
sulphide sodium.
Microbic cleanliness. Water cleared should contain no more than
100 microorganisms in 1 ml.
Storage conditions (recommendations of the Pharmacopoeia of
Japan are thus used): “water store in the closed bottless from
materials, which do not change properties of water and protect it
from foreign particles and microbic pollution”.
Application
Water cleared is water for preparation of medical drugs, except
what should be sterile and depyrogenized.
British Pharmacopoeia 2009
SPU, add.1
Hydrogen Peroxide Solution (3 per cent)
General Notices
H2O2
Dilute Hydrogen Peroxide Solution
(Ph Eur monograph 0395)
Hydrogenii peroxidum 3 per centum
Solutio Hydrogenii peroxydi diluta
Hydrogeniun peroxydatum
DEFINITION
Content
2.5 per cent m/m to 3.5 per cent m/m of H2O2 (Mr 34.01).
1 volume of hydrogen peroxide solution (3 per cent) corresponds to about
10 times its volume of oxygen. A suitable stabiliser may be added.
Appearance
CHARACTERS
Colourless, clear liquid.
OBTAINING
Interaction barium peroxide with acid (Tenar method, 1818):
ВаО2 + H2SO4  ВаSO4 + Н2О2
Identification
1. Reaction with K2Cr2O7 in the acid medium in the
presence of ether – formations of pechromic acids;
ethereal layer colouring in dark blue colour:
K2Cr2O7 + H2SO4 = K2SO4 + H2Cr2O7
O
H
O
Cr
O
O
Cr
O
O
O
O
O
H
+
H2O2
OH2
+
H
O
Cr
O
O
O
Cr
O
O
H
2. identification of stabilizer acetanilide
Acetanilide Н3ССОNНС6Н5 contains in a molecule acetylated an aromatic amino
group. That it to release, spend acid hydrolysis by heating of the dry rest with
chloride acid:
NHCOCH3
+
NH2
OH2
O
HCl
t
* HCL
+
CH3C
OH
Then spend reaction of identification of an aromatic amino group: for this purpose
use diazotization at interaction about sodium nitrite in the medium of chloride acid
with the subsequent condensation of the received salt diazonium with an alkaline
solution -naphthol with formation of azo dye red colour.
+
NH2
N
+ NaNO2 +
+
N
N
2 HCl
Cl
N
+
NaCl + 2 OH2
HO
OH
Cl +
+ NaOH
N
N
+
NaCl
+ OH2
Assay
1. Permanganstometry, direct titration (indicator-free a method).
Defined volume of an investigated solution of a hydrogen peroxide dilute of
water in a volumetric flask to defined volume, acidify a solution of sulphatic
acid and titrate by means of standard solution of potassium permanganate
KMnO4 before light pink colouring (at the expense of a excess drop of titrant
in an equivalence point):
5H2O2 + 2KMnO4 + 3H2SO4 = 2MnSO4 + K2SO4 + 5O2 + 8H2O
MnO4– + 8H+ + 5 e  Mn2+ + 4H2O | 5 | 2
H2O2 – 2e  O2o + 2H+
|2|5
–
+
2+
5H2O2 + 2MnO4 + 6H  2Mn + 5O2 + 8H2O
Еm=М.m./2
2.
Iodometry,
substitute
titration
(indirect
titration
(on
the
assistant)). To a solution of preparation H2O2 add excess of a solution KI,
acidify sulphatic acid H2SO4 and allocated iodine I2
titrate
by means of a
solution of sodium thiosulphate Na2S2O3 in the presence of starch (before
disappearance of dark blue colouring):
H2O2 + 2KI + H2SO4 = I2 + K2SO4 + 2H2O
2I– – 2е  I20
|1
H2O2 + 2H+ + 2е  2H2O| 1
H2O2 + 2I– + 2H+  I2 + 2H2O
I2 + 2Na2S2O3 = 2NaI + Na2S4O6
I2 + 2е  2I–
2S2O32– – 2е  S4O62–
Еm(H2O2) =М.м./2
Еm(Na2S2O3) = М.м.
3. Stabilizer Na-benzoate define by means of method of
direct acidimetry with the help with chloride acid HCl in the
presence of an ether (the ether takes insoluble in water benzoic
acid) with indicator use - mixes methyl orange and methylene
dark blue; in a point of equivalence the water layer is painted in
lilac (light violet) colour.
С6Н5СООNa + HCl = C6H5COOH + NaCl
Storage. In banks with ground glass stoppers, in
the cool place protected from light. The list of
strong substances.
Application. Antiseptic, disinfectant,
hemostatic agent. If in the recipe concentration is
not specified, release 3 % solution of Н2О2. Apply
to rinsings and washings at diseases of mucous
membranes (a stomatitis, quinsy), gynecologic
diseases. Shows hemostatic action. Apply as
depigmentation agent in cosmetology.
British Pharmacopoeia 2009
SPU, add. 1
Hydrogen Peroxide Solution (30 per cent)
General Notices
(Ph Eur monograph 0396)
H2O2
Hydrogenii peroxidum 30 per centum
Solutio Hydrogenii peroxydi concentrata
Hydrogeniun peroxydatum
Perhydrolum
34,01
DEFINITION
Content
29.0 per cent m/m to 31.0 per cent m/m of H2O2 (Mr 34.01). 1 volume of
hydrogen peroxyde solution (30 per cent) corresponds to about 110 times
its volume of oxygen. A suitable stabiliser may be added.
CHARACTERS
IDENTIFICATION, TESTS and ASSAY the same as for hydrogen
peroxide solution (3%).
Action and use
Antiseptic; deodorant.
When hydrogen peroxide is prescribed or demanded, Hydrogen
Peroxide Solution (6 per cent) shall be dispensed or supplied.
Ph Eur
Hydroperitum
Hydroperitum
H2NCONH2H2O2
The preparation represents a mix equimolar quantities of urea
H2NCONH2 and a hydrogen peroxide Н2О2 with addition of 0,08 % of a
solution of citric acid as conserving agent. Contains 33-35 % Н2О2.
Properties. A crystal powder of white colour, freely soluble in water,
soluble in alcohol.
Identification
1. Reaction on Н2О2.
Formations of pechromic acids after
interaction with K2Cr2O7 in the sulphate-acid medium in the
presence of ether –ethereal layer colouring in dark blue colour:
K2Cr2O7 + H2SO4 = K2SO4 + H2Cr2O7
O
H
O
Cr
O
O
Cr
O
O
O
O
O
H
+
H2O2
OH2
+
H
O
Cr
O
O
O
Cr
O
O
H
Biuret reaction to urea presence: at slow heating to temperature 150160 °С urea decays with allocation of ammonia NH3 and formation of ureido
formamide (biuret) H2NCONHCONH2:
2.
O
C
H2N
t
NH2
O
C
HN
+
NH3
isocyanic acid
HN
C
O
+
H2N
C
t
NH2
H2N
O
O
ureido
formamide
(biuret)
tautomerism:
NH2
C
O
NH
C
O
NH2
NH
C
O
C
NH2
imide form
NH
C
NH
OH
C
O
NH2
At interaction ureido formamide (biuret) (in the imide form) with ions
of Copper (ІІ) in alkaline solutions the characteristic violet colouring,
caused by formation chelate complex is observed:
2 O
C
NH2
NH
C
NH
OH
+Cu
OH
O
C
NH
C
OH
Cu
NH2
N
2
violet colouring
2. Iodometry, substitute titration (indirect titration (on the
assistant)). – see Н2О2.
Assay
Storage. In the dense corked containers, in the dry place
protected from light, at temperature not more then 20 °С.
Application. An antiseptic (instead of a hydrogen
peroxide).
Tablets of hydroperitum on 0,15 g, which should contain
not less than 0,48 g Н2О2. One tablet corresponds 15 ml 3
%-s' solution of Н2О2. Preparation action is based on
allocation Н2О2 at dissolution of hydroperitum in water. At
dissolution of one tablet in 200 ml of water receive 0,25 %
a solution of hydrogen peroxide. Use for mouth and throat
rinsing at stomatitises and angina.
BrPh 2007
SP X
(Ph Eur monograph 1540)
Magnesium peroxide
Magnesii peroxydum
MgO2  MgO
Magnesium peroxydatum
Magnium peroxydatum
The preparation contains not less than 25 % magnesium peroxide
MgO2 and 75 % magnesium oxide MgO.
Obtaining
1. Interaction magnesium chloride with alkali and hydrogen
peroxide at temperature 7-8 °С:
MgCl2 + 2KOH = 2KCl + MgO + H2O
MgO + H2O2 = MgO2 + H2O
2. Electrolysis 20% solution of
cathod forming MgO2.
magnesium chloride
MgCl2 – on the
Properties
The description. Magnesium peroxide represents a white
crystal powder without a smell.
Solubility. It is practically insoluble in water, soluble in
mineral acids and boiling acetic acid СН3СООН with allocation
H2O2:
MgO2 + 2HCl = MgCl2 + H2O2
Identification
1. Reaction on Н2О2 (after dissolution in mineral acid). Formation
perchromic acids at interaction with potassium dichromate K2Cr2O7
in sulphate-acid medium H2SO4 in the presence of an ether;
occurrence of dark blue colouring of an ethereal layer (chemism to
see the hydrogen peroxide Н2О2) is observed.
MgO2 + H2SO4 = MgSO4 + H2O2
H2O2 + H2Cr2O7 = H2Cr2O8 + H2O
1. Reaction on cations of Mg2+ (after dissolution in mineral acid).
MgO2 + H2SO4 = MgSO4 + H2O2
MgSO4 + Na2HPO4 + NH4OH
+ H2O
NH Cl
4

Assay
Permanganatometry, direct titration
MgNH4PO4 + Na2SO4
(after dissolution in
mineral acid).
MgO2 + 2HCl = MgCl2 + H2O2
(chemism to see the hydrogen peroxide Н2О2); Еm=М.м./2.
2. Iodometry, substitute titration (see Н2О2).
MgO2 + 2KI + H2SO4 = I2 + K2SO4 + MgSO4 +
2H2O
MgO2 + 4H+ + 2е  Mg2+ + 2H2O| 1
2I– – 2е  I20
|1
MgO2 + 2I– + 4H+  Mg2+ + I2 + 2H2O
I2 + 2Na2S2O3 = 2NaI + Na2S4O6
I2 + 2е  2I–
2S2O32– – 2е  S4O62–
Еm(MgO2) = М.м./2
Еm(Na2S2O3) = М.м.
Storage. In dense corked containers, protecting from action of a moisture and
carbon dioxide gas CO2.
Application. Antiseptic and adsorbtion agent.
Magnesium peroxide apply oral on 0,25-0,5 g 3-4 times a day as an antiseptic
at intestinally-gastric diseases (dispepsia, fermentation in a stomach, a
diarrhoeia).
Potassium permanganate
General Notices
(Ph Eur monograph 0121)
Kalii permanganas
KMnO4
Kalium hypermanganicum
158.0
DEFINITION
Content
99.0 per cent to 100.5 per cent.
In nature Manganese meets in the form of a mineral pyrolusite
MnO2.
Obtaining
1. Fusion of pyrolusite MnO2 with alkali in the presence of
oxidizers. At blowing off hot air it is formed manganate K2MnO4
(green colour), which under the influence of a strong oxidizer is
oxidised to permanganate KMnO4 according to schemes:
t
2K2MnO4 + 2H2O
а) 2MnO2 + 4KOH + O2 
MnO2 + 4OH– – 2е  MnO42– + 2H2O
O2 + 4H+ + 4е  2H2O
2MnO2 + 4OH– + O2  2MnO42– + 2H2O
б) 2K2MnO4 + Cl2 = 2KMnO4 + 2KCl
MnO42– – 1е  MnO4–
Cl2 + 2е  2Cl–
2MnO42– + Cl2  2MnO4– + 2Cl–
Properties
The description. Dark-violet or red-violet crystals or a small crystal
powder with metal shine. At grinding with some organic substances and various
reducers (the sulphur, the activated coal) can occur to explosion. At heating to
temperature 240 °С decays (intramolecular ORR):
2KMnO4  К2MnO4 + MnO2 + 5O2
Solubility. Soluble in water, freely soluble in boiling water, ethanol and
acetone.
Identification
1. Reaction of decolouration of a solution of a preparation at
action a hydrogen peroxide in the acid medium: the test solution
of potassium permanganate KMnO4 acidify diluted sulphatic acid
H2SO4 and add a solution a hydrogen peroxide H2O2; solution
decolouration (formation of Mn2+ ions ) is observed:
2KMnO4 + 5H2O2 + 3H2SO4 = 2MnSO4 + K2SO4
+ 5O2 + 8H2O
MnO4– + 8H+ + 5e  Mn2+ + 4H2O | 5 | 2
H2O2 – 2e  O2o + 2H+
|2|5
2MnO4– + 5H2O2 + 6H+  2Mn2+ + 5O2 + 8H2O
2. Reactions for ions of Potassium (K+) after heating of test
solution with 90 % ethanol (until decolouration of solution):
3C2H5OH + 2KMnO4 = 3CH3CНO + 2MnO2 +
2КОН + 2Н2О
MnO4– + 2H2О + 3e  MnО2 + 4ОH–
С2Н6О + 2ОH–– 2е  С2Н4О + 2Н2О
2MnO4– + 3C2H5OH  2MnО2 + 3CH3CНO +
2ОH– + 2Н2О
Filtrate (on the foilter paper is precipitate of MnO2, in the
filtrate is ions of Potassium) and do reactions for ions of K+.
a) SPU: reaction with tartrate acid Н2С4Н4О6; it is
formed white crystal precipitate of potassium hydrogentartrate:
Н2С4Н4О6 + К+ → КНС4Н4О6 + Н+
O
C
H
C
O
C
OH
OH
H
+
H
C
OH
K
C
OH
OH
+
+
H
C
O
C
OK
H
+
OH
O
C
OH
b) SPU: reaction with sodium cobaltinitrite
Na3[Co(NO2)6] in the medium of СН3СООН; the yellow
precipitate is formed:
2КCl + Na3[Co(NO2)6] → K2Na[Co(NO2)6]↓ + 2NaCl
2К+ + Na+ + [Co(NO2)6]3– → K2Na[Co(NO2)6]↓
c) SPU, N: Salts of Potassium paints a colourless flame in
violet colour (at examining through dark blue glass - purple-red):
К+ + h  *К+  К+ + h1
Assay
1. Iodometry, substitute titration (see Н2О2).
2КMnO4 + 10KI + 8H2SO4 = 2MnSO4 + 5I2 + 6K2SO4 +
8H2O
MnO4– + 8H+ + 5e  Mn2+ + 4H2O
2I– – 2е  I20
2MnO4– + 10 I– + 16H+  2Mn2+ + 5I2 + 8H2O
I2 + 2Na2S2O3 = 2NaI + Na2S4O6
I2 + 2е  2I–
2S2O32– – 2е  S4O62–
Еm(Na2S2O3) = М.м.
Еm(КMnO4) = М.м./5
Storage. In the banks from orange glass with plastic stoppers, in
the place protected from light.
Application. An antiseptic.
Apply to washing of wounds (0,1-0,5 % solutions), for throat and
mouth rinsing (0,01-0,1 % solutions); for greasing of burns and
ulcers (2-5 % solutions) (the skin is dried and bubbles are not
formed); for syringings and washings in gynecologic and
urological practice (0,02-0,1 % solutions). At poisonings
alkaloids, cyanides and phosphorus wash out a stomach
0,02-0,1 %-s' solutions of a preparation.
Antimicrobic action is possible explain allocation of atomic
Oxygen at preparation dissolution in water:
KMnO4 + H2O = 2KOH + 2MnO2 + 3O
British Pharmacopoeia 2009
General Notices
SPU, add. 1
Sulphur for External Use
(Ph Eur monograph 0953)
Sulfur ad usum externum
32.07
S
DEFINITION
Content
99.0 per cent to 101.0 per cent.
Obtaining
1. Milling of sulfurs cleared (Sulfur depuratum) at colloidal mills
before obtaining of an amorphous powder of citreous colour.
Sulphur cleared receive from sulfuric colour, which clear of
impurity of sulphides Arsenic, and also from acids sulphatic and
sulphitic. With that end in view sulfuric colour process an ammonia
solution. Thus impurity of acids and Arsene's compounds pass in
corresponding soluble salts (thioarsenites and arsenites or
thioarsenates and arsenates ):
As2S3 + 6NH4OH = (NH4)3AsS3 + (NH4)3AsO3 +
H2O
As2S5 + 24NH4OH = 3(NH4)3AsO4 +
5(NH4)3AsS4 + 12H2O
H2SO4 + NH4OH = (NH4)2SO4 + 2H2O
CHARACTERS
Appearance
Yellow powder.
Solubility
Practically insoluble in water, soluble in carbon disulphide, slightly soluble in vegetable
oils. mp: about 120 °C.
The size of most of the particles is not greater than 20 µm and that of almost all the
particles is not greater than 40 µm.
IDENTIFICATION
A. (BrPh, SPU, add. 1). Burning of sulphur. Heated in the presence of air, it
burns with a blue flame, emitting sulphur dioxide which changes the colour of
moistened blue litmus paper R to red.
S + O2  SO2
SO2 + Н2О  Н2SO3  2Н+ + SO32–
B. (BrPh, SPU, add. 1). Reaction for sulphate ions after oxidation by
means of bromine water. Heat 0.1 g with 0.5 ml of bromine water R until
decolourised. Add 5 ml of water R and filter. The solution gives reaction (a) of
sulphates (2.3.1).
S + 3Br2 + 4H2O 6HBr + H2SO4
bromine water
decolourised solution
SO42– + Ва2+  ВаSO4
white precipitate
ASSAY
(BrPh, SPU, add. 1). Alkalimetry after burning of test substance.
Carry out the oxygen-flask method (2.5.10) , using 60.0 mg in a 1000
ml combustion flask. Absorb the combustion products in a mixture of 5
ml of dilute hydrogen peroxide solution R and 10 ml of water R. Heat to
boiling, boil gently for 2 min and cool. Using 0.2 ml of phenolphthalein
solution R as indicator, titrate with 0.1 M sodium hydroxide until the
colour changes from colourless to red.
Carry out a blank titration under the same conditions.
1 ml of 0.1 M sodium hydroxide is equivalent to 1.603 mg of S.
S + O2  SO2
SO2 + Н2О2  Н2SO4
Н2SO4 + 2NaOH = Na2SO4 + 2H2O
S 
Н2SO4  2NaOH
1 mol
1 mol
2 mol
2 equivalent
2 equivalent
Еm(S) = А.m./2
Protected from light.
Keratolytic.
STORAGE
Action and use
British Pharmacopoeia 2009
SPU, add. 1
Sodium Thiosulphate
General Notices
(Ph Eur monograph 0414)
Natrii thiosulfas
Natrium hyposulfurosum
Natrium thiosulfuricum
Na2S2O3  5H2O
Chemical name: Sodium thiosulphate pentahydrate
O
ONa
O
S
O
ONa
S
SNa
S
248.2
DEFINITION
Content
99.0 per cent to 101.0 per cent of Na2S2O3,5H2O.
ONa
OBTAINING
1. Boiling of sulphur with sodium sulphite solution
Mix of S and Na2SO3 boiling until, then at additional of СаCl2 from solution
any more precipitated CaSO3:
Na2SO3 + S = Na2S2O3
СаCl2 + Na2SO3 = CaSO3 + 2NaCl
Sodium sulphate to clear and to dry in the air.
2. Interaction of sodium sulphide with sulphur(IV) oxide:
2Na2S + 3SO2 = 2Na2S2O3 + S
Appearance
CHARACTERS
Transparent, colourless crystals, efflorescent in dry air.
Solubility
Very soluble in water, practically insoluble in ethanol 96 per cent. It dissolves in its
water of crystallisation at about 49 °C.
Identification
1. Reactions to ions Na+ (see sodium fluoride):
a) Interaction with potassium pyroantimonate; the white
precipitate is formed;
b) Reaction with methoxyphenylacetate acids reagent; the white
precipitate is formed;
c) With a zinc-uranyl-acetate solution; the yellow precipitate is
formed;
d) Colouring of a colourless flame in yellow colour.
2. Reactions on thiosulphate-anions S2O32–.
a) Interaction with a solution of silver nitrate AgNO3 : at first
is formed white precipitate Ag2S2O3, which quickly turns yellow (S).
At standing, under the influence of a moisture of air the precipitate
blackens as a result of allocation of silver sulphide Ag2S:
Na2S2O3 + 2AgNO3 = Ag2S2O3 + 2NaNO3
Ag2S2O3 = Ag2SO3 + S
Ag2SO3 + S + H2O = Ag2S + H2SO4
b) Interaction with chloride acid HCl; the yellow precipitate of
sulphur S is formed and allocation of gas SO2, having a smell of
burned sulphur:
Na2S2O3 + 2HCl = 2NaCl + S + SO2 + H2O
Assay
Iodometry, direct titration by standard solution of iodine I2 n the
presence of starch before occurrence of dark blue colouring:
2Na2S2O3 + I2 = 2NaI + Na2S4O6
2S2O32– – 2е  S4O62–
I2 + 2е  2I–
2S2O32– + I2  S4O62– + 2I–
Еm(Na2S2O3) = М.м
Storage. In a cool place, in well corked utensils from dark glass,
because light promotes its decomposition. Solutions of sodium
thiosulphate at standing grow turbid from allocated sulphur. This
process is accelerated in the presence of СО2 air. Therefore the
utensils with solutions of sodium thiosulphate is supplied calcium
chloride tube, which absorbs air carbonic acid.
Application.
Anti-inflammatory, desensitizing, detoxic agents.
For scabies treatment use a liquid.
British Pharmacopoeia 2009
General Notices
Nitrous Oxide
(Ph Eur monograph 0416)
Nitrogenium oxydulatum
“Laughing” gas
Oxydum Nitrosum
N2O
Structural formula:
N
N
O
Nitrogen(I) oxide has opened in 1776 year Priestley at
interaction of iron with nitrate acid.
Obtaining
1. Thermal decomposition of ammonium nitrate :
NH4NO3
t


N2O + 2H2O
SP X
Appearance
Solubility
CHARACTERS
Colourless gas.
At 20 °C and at a pressure of 101 kPa, 1 volume dissolves in about 1.5
volumes of water.
PRODUCTION
Nitrous oxide is produced from ammonium nitrate by thermic decomposition.
First identificationэA.
Second identificationэB, C.
IDENTIFICATION
A. It complies with the limits of the assay.
B. (BrPh 2009, SP X). Place a glowing splinter of wood in the
substance to be examined. The splinter bursts into flame.
C. Introduce the substance to be examined into alkaline pyrogallol
solution R (BrPh 2009) (or nitric oxide NO – SP X). A brown colour does
not develop.
(Unlike Oxigen):
N2O + NO  NO2
ASSAY
Infrared analyser (2.5.35).
Gas to be examined. The substance to be examined. It must be
filtered to avoid stray light phenomena.
Reference gas (a). Nitrous oxide R.
Reference gas (b). A mixture containing 5.0 per cent V/V of
nitrogen R1 and 95.0 per cent V/V of nitrous oxide R. Calibrate the
apparatus and set the sensitivity using reference gases (a) and (b).
Measure the content of nitrous oxide in the gas to be examined.
STORAGE
Store liquefied under pressure in suitable containers complying with the legal
regulations. The taps and valves are not greased or oiled.
Action and use
General anaesthetic; analgesic.
Nitrous oxide should be kept in approved metal cylinders which are painted
blue and carry a
label stating 'Nitrous Oxide'. In addition, 'Nitrous Oxide' or the symbol 'N2O'
should be
stencilled in paint on the shoulder of the cylinder.
British Pharmacopoeia 2009
SP X
Sodium nitrite
General Notices
(Ph Eur monograph 1996)
Natrii nitris
Natrium nitrosum
69.0
NaNO2
DEFINITION
Content
98.5 per cent to 100.5 per cent (dried substance).
OBTAINING
1. From wastage (nitrose gases with NO2) at production of
nitric acid:
2NO2 + Na2СО3 = NaNO3 + NaNO2 + СО2
solution
2. The reduction of sodium nitrate by means of Lead:
NaNO3 + Pb = PbО + NaNO2
Appearance
CHARACTERS
Colourless crystals or mass or yellowish rods, hygroscopic.
Solubility
Freely soluble in water, soluble in alcohol.
Water solution of sodium nitrite is hydrolysed and have
alkaline reaction:
NO2– + HOH  HNO2 + OH–
Identification
1. Reactions to ions Na+ (to see sodium fluoride):
a) Interaction with potassium pyroantymonate; the white
precipitate is formed;
b) Reaction with methoxyphenylacetic acid; the white
precipitate is formed;
c) Reaction of flame; flame paints in yellow colour.
2. Reactions for nitrite-anions NO2–:
A. (BrPh). Dilute 1 ml of solution S1 (see Tests) to 25 ml with water R. To 0.1
ml of the solution add 1 ml of sulphanilic acid solution R1. Allow to stand for
2-3 min. Add 1 ml of b-naphthol solution R and 1 ml of dilute sodium
hydroxide solution R. An intense red colour develops.
B. (BrPh, SPU, N). Reaction of formation nitrosophenazone. To 1
ml of the solution prepared for identification test A add 3 ml of a 20 g/l solution
of phenazone R and 0.4 ml of dilute sulphuric acid R. An intense green colour
develops.(difference from nitrates):
CH3
H
O
N
N
C 6H5
CH3
+
HO
N
O
NaNO2
HCl
O
CH3
N
O
N
N
CH3
+
OH2
+
NaCl
C 6H5
OTHER REACTIONS:
1. Reaction with diphenylamine in the acid medium (conc.
H2SO4) with formation of organic dye of is bright-dark blue colour:
2
NH
H2SO4
NH
NH
+ NO2
H2SO4
+
N
N
HSO4
H
2. Reaction with acids: at addition to a solution of a preparation of dissolved
sulphatic acid H2SO4 red-brown steams a nitrogen dioxide NO2 (at the expense of
decomposition НNO2) are allocated:
NaNO2 + H2SO4 = Na2SO4 + NO + NO2 + H2O
ASSAY
Permanganatometry, back titration with iodometric finishing:
defined volume of investigated preparation NaNO2 pour in in the
mix, consisting of excess of a standard solution of potassium
permanganate KMnO4 and diluted sulphatic acid H2SO4:
5NaNO2 + 2KMnO4 + 3H2SO4 = 5NaNO3 +
2MnSO4 + K2SO4 + 3H2O
MnO4– + 8H+ + 5e  Mn2+ + 4H2O
NO2– + Н2О – 2е  NO3– + 2Н+
2MnO4– + 5NO2– + 6H+  2Mn2+ + 5NO3– +
3H2O
After 20 minutes to a reactionary mix add crystal КI (reacts with
excess KMnO4) and allocated iodine I2 titrate by means of sodium
thiosulphate Na2S2O3 in the presence of starch (before
disappearance of dark blue colouring):
2KMnO4 + 10KI + 8H2SO4 = 5I2 + 2MnSO4 + 6K2SO4 +
8H2O
–
+
MnO4 + 8H + 5e  Mn2+ + 4H2O
2I– – 2е  I20
2MnO4– + 10 I– + 16H+  2Mn2+ + 5I2 + 8H2O
I2 + 2Na2S2O3 = 2NaI + Na2S4O6
I2 + 2е  2I–
2S2O32– – 2е  S4O62–
Еm(NaNO2) = М.м./2
Еm(Na2S2O3) = М.м.
Carry out a blank titration (the technique is analogous, only
without an investigated preparation).
Content NaNO2 in a preparation in % to calculate by mean of
formula:
Storage
Considering, that the preparation hygroscopic and easily is
oxidised on air, store it in a dark place, in well corked glasses of
orange glass. At infringement of conditions of storage the
preparation blurs and turns yellow there of allocation of
nitrogen(IV) oxide. The list of strong substances.
Action and use
Used in treatment of cyanide poisoning.
Ph Eur
Spasmolytic (coronarodilator) agent.
Apply intake (on 0,1-0,2 g on reception) or hypodermically in
the form of 1 %-s' solution as coronarodilator agent at a
stenocardia. At a poisoning of cyanides enter intravenously 10-20
ml 1-2 %-s' solutions of a preparation. Thus, sodium nitrite is an
antidote at a poisoning of methemoglobin former substances.
Thanks for attention!