REPUBLIC UZBEKISTAN MINISTRY OF HEALTH
THE CENTER OF DEVELOPMENT OF THE MEDICAL
EDUCATION
THE TASHKENT MEDICAL ACADEMY
« Approve »
Vicerector of study process,
professor__________ O R Teshaev
«_____»_____________2013
Chair: BIOORGANIC AND BIOLOGICAL CHEMISTRY
Subject: BIOINORGANIC CHEMISTRY
THEME: BUFFER SOLUTIONS
The Educational-methodical grant
(For teachers and students of the higher medical educational institutions)
Tashkent 2013
The composer:. A.D. Juraev - the professor of chair of bioorganic and biological
chemistry ТМА
U.A. Baltabaev- the professor of chair of bioorganic and biological
chemistry ТМА
N.A.Mahsumova - assistant of chair of bioorganic and biological
chemistry ТМА
Reviewers:. - Sharipov H.Tmanaging chair of analytical chemistry and technology of
precious metals of the Tashkent chemico-institute of technology, the
Doctor of Chemistry, the professor.
The methodical recommendations of reviewed and approved
at the faculty meeting. Protocol № "____" ________________2013 y
The methodical recommendations of reviewed and approved
CMK meeting on medical and biological section.
Protocol № "____" ________________2013 y
THEME: BUFFER SOLUTIONS
1. A place of carrying out of employment, equipment
- Chair of bioorganic and biological chemistry
- A set of laboratory chemical ware, visual aids, a distributing material, slides
- Reactants: physiological buffer solutions, acetic acid and its salts
- codoscope, a multimedia projector
2. Duration of employment
- 3 hours
3. The employment purposes:
- To learn students to concepts about buffer systems, about their properties,
calculation methods рН and buffer capacity of solutions
- To learn to understand the reasons of maintenance of a constancy рН
environments buffer solutions, by examining of the mechanism of action of
buffer solutions
- To explain to students necessity of the received knowledge for medical
researches and to explain their value
- To explain to students of the reason of a constancy рН environments of
biological liquids
- To learn to prove theoretical knowledge carrying out of laboratory works
- To learn to feel responsibility for the spent works
- To develop at students ability freely to think and do logic conclusions
Problems:
The student should know:
- Structure and types of buffer solutions
- Buffer systems of an organism
- The mechanism of action of buffer solutions
- Formulas for calculation рН buffer solutions
- Formulas for calculation of buffer capacity
The student should be able:
- To write structure of buffer solutions
- To calculate рН buffer solutions
- To define buffer capacity
- To prepare buffer solutions
- To measure рН buffer solutions with the help рН metre
4. Motivation
The human body has constant value рН environments. As the reason for
it presence at a human body of buffer systems serves. There is a necessity of
studying of structure, properties of buffer solutions to understand all system of
work of a human body.
5. Intersubject and intrasubject communications
Mastering of the given theme by students is based on knowledge of
versions of salts, their hydrolysis, the law of action of weights, a hydrogen
indicator, on knowledge of biological liquids in a human body. The mastered
knowledge will be necessary in such directions as: biological chemistry, normal
and pathological physiology, pharmacology, therapy, surgery and other clinical
disciplines.
6. The employment maintenance
6.1 Theoretical part
One of characteristic properties of the internal environment of organisms
is the constancy of concentration of hydrogen ions (izogidry). Preservation of a
constancy of concentration is provided with joint action of some physical and
chemical and physiological mechanisms from which very important role
belongs to buffer systems.
рН the indicator of acids and alkalis varies eventually. The inconstancy
reason рН an indicator is partial dissolution of the substances which are in air
and as a part of glasswares.
The mix of a solution of acetic acid from it sodium salt at addition in it of
a small amount of strong acid or alkali or at generated does not change the size
рН Property of solutions to keep invariable рН indicator is called as buffer
action. The solutions possessing this property, are called as buffer solutions. On
structure buffer solutions share on following groups:
1. A mix of weak acid and salt, generated this acid with the strong basis.
2. A mix of the weak basis and its salt with strong acid.
In practice following buffer solutions more often are considered:
СН3СООН + СН3СООNa - acetate a buffer solution
H2CO3 + NaHCO3 - bicarbonate a buffer solution
Na2HPO4 + NaH2PO4 - a phosphatic buffer solution
NH4OH +NH4Cl - an ammoniac buffer solution
PtCOOH + PtCOONa - an albuminous buffer solution
HHb + KHb - hemoclobine a buffer mix
HhbО2 + KhbО2 - oxihemoglobinea buffer mix
In a human body the constancy рН biological liquids is supported for the
account of these buffer mixes, behind an exception acetete and ammoniac
buffer mixes.
The mechanism of buffer action consists in formation of weak electrolit,
instead of stronger electrolit. For example at addition in acetate a buffer mix of
small amounts of strong acid (HCl) co-operate with acetate ions, generate at
dissociation strong electrolit of acetate of sodium and form weak electrolit
acetic acid. At addition in this buffer mix of alkali (NaOH), gidroxile ions cooperate with the hydrogen ions formed as a result of partial dissociation of
weak electrolit of acetic acid with formation of weak electrolit of water, and
value рН remains to a buffer mix practically invariable.
Size рН buffer solutions raschityvaetsya by means of equation
Gendersona-Hasselbach:
pH = pK кисл + lg Ssoli/From pussycats s and
pH = 14 - pK осн. - lg Ssoli/With осн.
Thereby рН a buffer solution it is defined by a parity of concentration of salt
and acid or the basis.
Property of buffer solutions to keep constant concentration of hydrogen
ions, depends on quantity of added acid or alkali in a solution and is defined by
buffer capacity. As buffer capacity is called the quantity mole added strong acid
or the basis, which is necessary for adding to one litre of a buffer solution to
change size рН to one unit:
B = With / рН0 - рН1 mmol/l
Here In - buffer capacity
With - quantity of strong acid or alkali in mole
рН0 - A hydrogen indicator of a solution before acid or alkali addition
рН1 - A hydrogen indicator after acid or alkali addition
The buffer capacity of buffer solutions depends on concentration of
components and their nature.
The new pedagogical technologies used on employment:
"Cluster".
Cluster - beam bunch - a method for making of map information gathering ideas around a main factor for determining the meaning and focus of
the assembly. Stimulates actualization knowledge helps freely and openly
engage in the thought process of the new association presentation on the topic.
Rules of conduct:
1. Students are divided into three small groups
2. Acquainted with the rules for cluster
3. In the center of the chalkboard or a large piece of paper written in a key word
or topic name of 1-2 words
4. By association with the keyword attribute the side of it in the circles smaller
"satellite" - the words or sentences that are related to the topic. Connect their
lines with the "main" word. These "satellite" can be "small satellites", etc.
5. Record goes before the allotted time or until exhausted ideas
6. Then combined into small groups, compare, exchange clusters for discussion
7. Then provide the teacher to check. It shows students the correct, complete
responses.
8. A group of students wrote a large number of branches is given 30 points.
9. Other students 25 points, a group of students to write a smaller number of
branches is given 20 points.
10. After school, points scored for the graphic organizer added to the total score
of the students received for the current control.
METHOD USE «the Cat in a bag»
The given method promotes active participation of each student in
discussion of a theme and allows to establish easily level of knowledge of the
student on the given employment.
Each student gets from "sack" that card with a question which will get to
it. Within 3 minutes students in writing answer the asked question and hand
over a card and the answer to the teacher. Then each question is discussed with
the assistance of the teacher and other students. Wrong answers are corrected
and supplemented with other students. The teacher estimates correctness of the
answer of the student answering the given question and activity of participation
of students, making corrections and additions.
Variants of questions:
1. Make definition of buffer solutions and result their examples
2. Tell about classification of buffer solutions
3. Tell about the mechanism of buffer action
4. Write the equation Genderson - Xasselbah for acid buffer systems
5. Write the equation Genderson - Xasselbah for the basic buffer systems
6. What buffer systems operate in a human body and in particular as a part of
blood?
7. Explain the mechanism of buffer action hydrocarbonate to a buffer mix.
What is the alkaline reserve of blood?
8. Make definition and write the formula of albuminous buffer system
9. Make definition and write the formula hydrocarbonate buffer system
10. Make definition and write the formula of phosphatic buffer system
11. Explain, why the solution of weak acid does not possess buffer action
12. How the buffer capacity pays off and whether influences attenuation size
рН a buffer solution?
6.2 Analytical part
Situational problems:
1. Calculate рН the physiological buffer system consisting from 7,5 ml of 0,1
normal solutions of hydrophosphate of sodium and 7,5 ml of 0,1 normal
solutions digydrophosphate of sodium, considering, that рК
digydrophosphate sodium is equal 7,2. The answer: 7,2
2. Calculate buffer capacity of whey of blood of 20 ml, considering, that at
addition in it of a solution of hydrochloric acid, comprising 2 mole chloride
hydrogen, рН a solution changes to 3,4. The answer of 25 mmol/l.
Situational tests:
1. Addition of strong acid or the basis in a buffer solution without considerable
change of value рН this solution has the certain limit.
A.How is called this limit?
Size РН of the buffer
Buffer capasity*
Concentration of the buffer
Acid or basis volume
Constant dissociation acids or the bases
What B.For of volume of a buffer solution it pays off?
10 litres
15 litres
1 литр*
5 litres
0,1 litre
V.Which the formula use for this purpose?
Ó¡ = - lg [H +]
Sm = m / MV
Кд = [AB] / [A +] n [B-] m
n=m/M
In = With / рН1 - рН0*
2. Buffer systems in an organism support constant value РН.
A.Which from the listed buffer systems has the basic an effect in blood?
The phosphatic
The ammoniac
gydrocarbonate*
acetate
The albuminous
B.Which a chemical compound of the chosen buffer system
NaH2PO4 + Na2HPO4
NaHCO3 + H2CO3 *
CH3COONa + CH3COOH
PtCOONa + Pt COOH
NH4Cl + NH4OH
V.Which process reflects the mechanism of buffer action at addition It - of ions
in the specified buffer system?
H2CO3 + OH - = HCO3 - + H2O*
H2PO4 - + OH - = HPO42 - + H2O
NH4Cl + OH - = NH4OH + Cl CH3COOH + OH - = CH3COO - + H2O
Pt COOH + OH - = Pt COO - + H2O
3. Buffer systems in an organism support constant value РН.
A.Which from the listed buffer systems has the basic an effect in an
endocellular liquid?
phosphate*
The ammoniac
gydrocarbonate
acetate
The albuminous
B.Which a chemical compound of the chosen buffer system
PtCOONa + Pt COOH
NaHCO3 + H2CO3
CH3COONa + CH3COOH
NaH2PO4 + Na2HPO4*
NH4Cl + NH4OH
V.Howoj process reflects the mechanism of buffer action at addition It - of ions
in the specified buffer system?
H2CO3 + OH - = HCO3 - + H2O
H2PO4 - + OH - = HPO42 - + H2O*
NH4Cl + OH - = NH4OH + Cl CH3COOH + OH - = CH3COO - + H2O
Pt COOH + OH - = Pt COO - + H2O
4. Buffer systems in an organism support constant value РН.
A.Which from the listed buffer systems has an effect in all cages and organism
fabrics?
The phosphatic
The ammoniac
gydrocarbonate
acetate
albuminous*
B.Which a chemical compound of the chosen buffer system.
NaH2PO4 + Na2HPO4
NaHCO3 + H2CO3
CH3COONa + CH3COOH
PtCOONa + Pt COOH*
NH4Cl + NH4OH
V.Which process reflects the mechanism of buffer action at addition It - of ions
in the specified buffer system?
H2CO3 + OH - = HCO3 - + H2O
H2PO4 - + OH - = HPO42 - + H2O
Pt COOH + OH - = Pt COO - + H2O*
CH3COOH + OH - = CH3COO - + H2O
NH4Cl + OH - = NH4OH + Cl 6.3 Experimental part
1. Preparation of solutions acetate buffer system with various values рН
The purpose: to Learn to prepare buffer solutions and to measure рН buffer
solutions by means of rn-metre and to count theoretical value рН on equation
Gendersona-Hasselbach
Carried out stages:
№a
stage
Action
It is not executed
(0 point)
It is executed
correctly
completely
1
To take 5 pure and dry flasks for
preparation of solutions
0
5
2
To pour in each flask certain volumes of
acetic acid of 0,1 M
0
10
3
To flow in each flask to a solution of
acetic acid certain volumes of a solution
of acetate of sodium of 0,1 M and to mix
solutions
0
10
4
To pour serially in electrolitic a glass the
prepared buffer solutions
0
5
5
To make a galvanic chain from glass and
chlor-silver electrodes
0
10
6
To press a key ionomer, intended for
measurement рН and to fix values рН
0
10
7
To calculate рН these solutions by
means of equation GendersonaHasselbach
0
30
2. Definition of buffer capacity of whey of blood
The purpose: to Learn to define buffer capacity of biological liquids
Carried out stages:
№a
stage
Action
It is not executed
(0 point)
It is executed
correctly
completely
1
To take 2 pure and dry flasks for
titration
0
5
2
To pour in both flasks on 5 ml of whey
of blood
0
5
3
To calculate a change interval рН,
correctly to pick up the indicator and to
pour it in a flask
0
20
4
To pour in burette a working solution
hydrooxide sodium and to result to a
zero point
0
10
5
In the presence of the indicator
phenolphthalein titrate a solution to an
equivalent point to measure volume of a
working solution
0
20
6
In burette to pour a working solution of
hydrochloric acid and to establish a zero
point
0
10
7
In the presence of the indicator methyl
orange titrate a solution to a point of
equivalence and to fix the spent volume
of a working solution
0
20
8
To calculate by means of formulas
buffer capacity of whey of blood on acid
and on the basis
0
10
7. Methods of check of experience and knowledge
- The oral
- The written
- A situational problem and the situational test
- Demonstration of the practical knowledge acquired on employment
Criteria of an estimation of the current control
№
Advance in
%
Estimation
1
96-100
Perfectly «5»
Knows the formulation of definition of a buffer
solution, buffer capacity, the mechanism of
buffer action and is able to calculate рН a buffer
solution. Knows equation Genderson Xasselbah, buffer systems of an organism.
Unmistakably and to destination uses laboratory
ware. Is able to solve situational problems. Sums
up and makes of the decision, creatively thinks,
independently analyzes. Independently and
without errors solves tests, actively, creatively
takes part in interactive methods of training,
suggests new ideas, results of works
independently makes out in laboratory magazine,
according to requirements. СРС it is executed
perfectly.
2
91-95
Perfectly «5»
Knows the formulation of definition of a buffer
Level of knowledge of the student
solution, buffer capacity, the mechanism of
buffer action and is able to calculate рН a buffer
solution. Knows equation Genderson Xasselbah, buffer systems of an organism.
Unmistakably and to destination uses laboratory
ware. Is able to solve situational problems.
During carrying out of calculations commits one
insignificant error. Sums up and makes of the
decision, creatively thinks, independently
analyzes. Independently and without errors
solves tests, actively, creatively takes part in
interactive methods of training, suggests new
ideas, results of works independently makes out
in laboratory magazine, according to
requirements. СРС it is executed perfectly.
3
4
86-90
81-85
Perfectly «5»
Well «4»
Knows the formulation of definition of a buffer
solution, buffer capacity, the mechanism of
buffer action and is able to calculate рН a buffer
solution. Knows equation Genderson Xasselbah, buffer systems of an organism.
Unmistakably and to destination uses laboratory
ware. Is able to solve situational problems.
During carrying out of calculations supposes 1-2
insignificant errors. Sums up and makes of the
decision, creatively thinks, independently
analyzes. Independently and without errors
solves tests, actively, creatively takes part in
interactive methods of training, suggests new
ideas, results of works independently makes out
in laboratory magazine, according to
requirements. СРС it is executed perfectly.
Knows the formulation of definition of a buffer
solution, buffer capacity, the mechanism of
buffer action and is able to calculate рН a buffer
solution. Knows equation Genderson Xasselbah, buffer systems of an organism.
Unmistakably and to destination uses laboratory
ware. Is able to solve situational problems.
During carrying out of calculations supposes 1
gross blunder. Is not able to sum independently
up and to make of the decision, independently
analyzes. Independently and without errors
solves tests, actively, creatively takes part in
interactive methods of training, suggests new
ideas, results of works independently makes out
in laboratory magazine, according to
requirements. СРС it is executed perfectly, but at
the report small discrepancies are admitted.
5
76-80
Well «4»
Knows the formulation of definition of a buffer
solution, buffer capacity, the mechanism of
buffer action and is able to calculate рН a buffer
solution. Knows equation Genderson- Xasselbah,
buffer systems of an organism. Is able to solve
situational problems. During carrying out of
calculations supposes 1-2 gross blunders. Is not
able to sum independently up and to make of the
decision, independently analyzes. Is mistaken at a
choice and use of laboratory ware. Takes part in
interactive methods of training, at the decision of
tests uses the help of the teacher, results of works
independently makes out in laboratory magazine,
according to requirements. СРС it is executed
well, but at the report small discrepancies are
admitted.
6
71-75
Well «4»
Knows the formulation of definition of a buffer
solution, buffer capacity, the mechanism of
buffer action and is able to calculate рН a buffer
solution. Knows equation Genderson Xasselbah, buffer systems of an organism. Is able
to solve situational problems. During carrying out
of calculations supposes 1-2 gross blunders. Is
not able to sum independently up and to make of
the decision, independently analyzes. Is mistaken
at a choice and use of laboratory ware. Takes part
in interactive methods of training, at the decision
of tests uses the help of the teacher, supposes 3-4
errors, results of works independently makes out
in laboratory magazine, according to
requirements. СРС it is executed well, but has
reported well.
7
66-70
Satisfactory
«3»
Knows the formulation of definition of a buffer
solution, buffer capacity, the mechanism of
buffer action. Knows equation Genderson Xasselbah, buffer systems of an organism. Is able
to solve situational problems. At calculation рН a
buffer solution and during carrying out of
calculations supposes gross blunders. Is not able
to sum independently up, to make of the decision
and independently to analyze. Is mistaken at a
choice and use of laboratory ware. Takes part in
interactive methods of training, at the decision of
tests uses the help of the teacher, supposes 3-4
errors, results of works independently makes out
in laboratory magazine, according to
requirements. СРС it is executed well, but has
reported uncertainly.
8
61-65
Satisfactory
«3»
Knows the formulation of definition of a buffer
solution, buffer capacity, does not know the
mechanism of buffer action. Knows equation
Genderson - Xasselbah, buffer systems of an
organism. Is able to solve situational problems.
At calculation рН a buffer solution and during
carrying out of calculations supposes some gross
blunders. Is not able to sum independently up, to
make of the decision and independently to
analyze. Is mistaken at a choice and use of
laboratory ware. Takes part in interactive
methods of training, at the decision of tests uses
the help of the teacher, supposes 3-4 errors, can
not independently issue results of works in
laboratory magazine. СРС it is executed on an
average level, and has reported uncertainly.
9
55-60
Satisfactory
«3»
Knows about buffer solutions and buffer
capacity, does not know the mechanism of buffer
action. Knows equation Genderson- Xasselbah,
buffer systems of an organism. Is not able to
solve situational problems. At calculation рН a
buffer solution and during carrying out of
calculations supposes gross blunders. Is not able
to sum independently up, to make of the decision
and independently to analyze. Is mistaken at a
choice and use of laboratory ware. Takes part in
interactive methods of training, but supposes
gross blunders, at the decision of tests uses the
help of the teacher and supposes set of errors,
cannot independently issue results of works in
laboratory magazine. СРС it is executed well. At
the report does not answer questions.
10
50-54
Unsatisfactory
«2»
Knows about buffer solutions. Does not know
exact definition of buffer solutions, buffer
capacity. Knows the mechanism of buffer action
on 1/3. On 50 % can correctly use laboratory
ware. Situational problems are solved incorrectly,
the majority of tests is solved incorrectly. Results
of works are issued incorrectly. Independent
work is executed incorrectly.
11
46-49
Unsatisfactory
«2»
Knows about buffer solutions. Does not know
accurate information of buffer solutions, buffer
capacity. Knows the mechanism of buffer action
on 1/4. On 40 % can correctly use laboratory
ware. Situational problems are solved incorrectly,
the majority of tests is solved incorrectly. Results
of works are issued incorrectly. Independent
work is executed incorrectly.
12
41-45
Unsatisfactory
«2»
Knows about buffer solutions. Does not know
accurate information of buffer solutions, buffer
capacity. Knows the mechanism of buffer action
on 1/5. On 30 % can correctly use laboratory
ware. Situational problems are solved incorrectly,
the majority of tests is solved incorrectly. Results
of works are issued incorrectly. Independent
work is executed incorrectly.
13
36-40
Unsatisfactory
«2»
Knows about buffer solutions. Does not know
formulating buffer solutions, buffer capacity.
Knows the mechanism of buffer action on 1/10.
On 20 % can correctly use laboratory ware.
Situational problems are solved incorrectly, the
majority of tests is solved incorrectly. Results of
works are issued incorrectly. Independent work is
not executed.
14
31-35
Unsatisfactory
«2»
Has no representation about buffer solutions.
Does not know their structure. Does not know the
formulation of buffer solutions, buffer capacity.
Does not know the mechanism of buffer action.
Is not able to use laboratory ware correctly.
Situational problems are solved incorrectly, is not
able to solve tests, the writing-book is issued
partially by means of the teacher. Independent
work is not executed.
9. Technology card of employment:
Flow chart classes
Training
1-Step. Introduction (10 min)
1.1. Announces theme class, purpose and expected
results. See the plan classes. Explain inter-subject
and inter-subject relationship.
1.2. provide basic notions of practical lessons, its
importance in medicine, introduction to literature,
used in the performance of independent work.
Learner
Listen and write
Find out, ask questions
1.3. Introduces the rating situation assessment.
2-Step. The major part (80 min)
2.1. Familiar with this implementation plan for the
practical classes
2.2. Assesses students' background knowledge using
new pedagogical technology: graphic organizer
" Cluster " business game " Brain storm ".
Work in small groups and
make presentations
2.3. Tools for learning provides students with visual
aids and gives them an explanation. Provides
guidance on the implementation of practical work.
2.4. students independently carry out work on the
stepper laboratory mastering practical skills.
3-phase. Final part (45min)
3.1. Assesses students' knowledge on the results of a Recitation, writing survey,
graphic organizer of educational technology
tests, test, results of
" Cluster " business game " Brain storm ".
practical work
3.2. to conclude on this lesson, students drew
attention to the importance of this lesson, students in
their future careers.
3.3. presentation is an independent work of students
on the topic 100-point system, and the results are
announced. Provides job next lesson and topic next
homework.
participate in the discussion
of individual work ask
questions! Record new job
9. A chronological card of employment
№
Employment stages
1
Opening address of the teacher (theme
substantiation)
2
Discussion of a theme of laboratory
research, definition of initial level of
knowledge of students with application of
new pedagogical technologies (small
groups, structural-logic scheme of
"Cluster", business game «Brain storm »,
situational problems)
3
Discussion summarising
The employment
form
Duration (135
mines)
5
Interrogation,
explanation
40
5
4
Representation to students of visual acids
(laboratory ware, the schemes, the training
program, etc.)
5
Independent work on mastering of practical
skills
Definition of
concentration of
acetic acid and
hydroxideа
ammonium in a
water solution
40
6
The control of mastering of a theoretical
part of employment, discussion of results of
practical work, their registration, estimation
of activity of group, according to the
reached purposes.
Oral interrogation, the decision
of tests, check of
registration of
experimental work
in writing-books,
group discussion of
results of employment.
15
7
Conclusions of the teacher about
employment results, an estimation of
activity of each student on 100 ball system
and their announcement. The announcement
of the task for following employment (the
complete set of questions)
The information,
questions for
independently
preparations
5
25
10. Control questions
1. What solutions are called as buffer?
2. Classification of buffer solutions
3. The mechanism of buffer action
4. Equation Genderson-Hasselbah
5. Influence attenuation on size of buffer capacity
6. Definition of buffer capacity of buffer systems
7. The buffer systems operating in a human body
8. What is the alkaline reserve of blood?
9. Albuminous buffer system
10. Gydrocarbonate buffer system
11. Whether the solution of weak acid possesses buffer action?
12. Why at preparation of a buffer solution use weak acid or the weak basis,
instead of strong?
13. What influence renders разбавление on size рН a buffer solution?
14. Biological value of buffer systems
11. The literature
The basic
1, A.D. Juraev, N.A.Alimhodzhaeva. Guide for General Chemistry.2005
2. Kasymov S.S.biogene elements. Tashkent, Publishing "Medicine" UzSSR,
1990
3. Glinka N.L.general Chemistry .-Leningrad "Chemistry", the Leningrad
branch, 1990.
4. The general and inorganic chemistry. Under A.F.Vorobyova's edition, М, ICC
« Academic book », 2004; 2, 2006
5. Moskalev JU.I.mineral an exchange. М, "Medicine", 1985.
6. Avtsyn A.P., Zhavoronkov A.A., Rish M. A, Strochkova h.p.
Microelementoses of the person. М, "Medicine", 1991.
7. Ahmetov N.S.general and inorganic chemistry. М, "Higher school", 2003.
The additional
4. Ravich-ShCherbo M. I, Annenkov G. A. Physical and colloidal
chemistry. "Medicine", Т, 1971
5. K.Hauskroft, E.Konstebl. A modern course of the general chemistry 2
volume. "World", 2002
6. J.A.Ugai. The general and inorganic chemistry. М: "Higher school",
2004