Water Chemistry

NAME OF THE COURSE Water Chemistry



Year of study


Course teacher

Asst Prof Marijo Buzuk

Credits (ECTS)


Associate teachers

Asst Prof Maša Buljac

Type of instruction (number of hours)






Status of the course


Percentage of application of e-learning

0 %


Course objectives

The main objective of this course is to understand the chemistry and kinetics that take place in natural waters (including the acid- base reactions in natural waters , complexation reactions , dissolution and precipitation , and redox reactions ) for students of chemistry, biology, ecology, geochemistry, etc. In addition to these field of natural sciences, the course offers the fundamental knowledge necessary for understanding processes in environmental engineering.

Course enrolment requirements and entry competences required for the course

It is required a good knowledge of general chemistry. Also, knowledge of analytical chemistry, physical chemistry, organic chemistry is useful but not obligates for understanding of lectures.

Learning outcomes expected at the level of the course (4 to 10 learning outcomes)

After course students will be able to :
1. explain the water cycle and the interactions that occur between different phases (water - air, water - solid)
2. to explain carbonate equilibrium, to understand concepts of alkality and buffering capacity of water; to understand the differences in composition, origin of solutes between surface water, groundwater and sea. This includes understanding of pc - pH graphs for open and closed systems. In addition, students will get insight of origin of the sea composition and control of composition of river and sea water.
3. understanding the correlation between the complex reactions (coordination chemistry) and bio-availability and toxicity of metals. This includes creating inorganic complexes and the interaction of heavy metals with organic (mainly humic) substances.
4. understand and calculate equilibrium conditions which lead to deposition in natural waters. This includes the performance of pc - pH graphs in open and closed systems with or without solid phase .
5. to assume that important redox equations can take place in a real system and to develop pe (pE) - pH - pc diagram for chosen species.
6. understand biologically important redox equations that take place under different conditions in natural waters

Course content broken down in detail by weekly class schedule (syllabus)

Lecture 1: Properties of water, structure of water molecules, the water composition (gases, compounds and ions in water , organic matter, trace elements , radioactive elements).
Lecture 2: The composition of sea water, the origin of salt and controls the composition of river and sea water elements in the sea ( permanent elements , circuit elements (nutrients ) adsorptive elements (precipitated elements) , ocean acidity).
Lecture 3: Interactions in the gas - water system , step changes
Seminar 1 (2 hours): Model and conditions of steady surface film - Solving problems and examples
Lecture 4: Carbonate system, Acid-base balance carbonate
Seminar 2 (2 hours): Calculation of pH and composition of the solution to carbonate species, drawing pc - pH diagrams for open and closed system .
Lab course 1 (4 hours): Introduction to methods of chemical analysis of water, Determination of total dissolved carbon, determination of dissolved inorganic carbon, determination of organic carbon
Lecture 5: The concentration of carbonate species in open and closed systems, Akalitet and acidity ( alkalinity and acidity)
Seminar 3 (2 hours): Calculation of alkalinity in water of different composition and nature (sea, river, rain, consumer)
Lab course 2 (4 hours): Determination of alkalinity various types of water (sea , river , rain ) , Determination of total nitrogen and total dissolved nitrogen.
Lecture 6: The metal ions in the aqueous solution , hydrolysis of the metal ion complexes with other inorganic ligands
Lecture 7: The metal ions and humic substances , properties of humic substances , Interaction of humic substances with metals, water hardness
Lab course 3 (4 hours ): Determination of metals in water (calcium, potassium , sodium, iron, zinc )
Lecture 8: Precipitation and dissolution equilibrium calculations , solubility and solubility product , conditional solubility product , log(c) pH diagrams (pc - pH)
Seminar 4 (2 hours ): Construction of PC - pH diagram for Ca2+ in equilibrium with the Ca(OH)2(s) and Mg2+ in equilibrium with Mg(OH)2(s)
Lecture 9: Solubility of salts of weak acids and bases, complexing Effect on solubility , precipitation of Fe(OH)2(s) and Fe(OH)3(s) (pc - pH diagrams), dominating diagrams of species.
Seminar 5 (2 hours): The precipitation of aluminum phosphate , Calculation of the equilibrium concentration of hydroxo complexes of iron , calcium carbonate solubility and stability of the water
Lecture 10: Redox reactions in water, the standard potential, Electronic activity and pe, pe- pc diagrams
Seminar 6 (2 hours): Construction of pe -pc (E-pc) diagrams (Fe species)
Lecture 11: pe - pH diagrams for Cl2 , Other diagrams dominance ( Br , I) , pe - pH (pH - E) plots in the presence of a of a solid phase
Seminar 7 (2 hours): Construction of pe - pH (pH - E) diagrams for chloric and brominated species. Construction of pe - pH diagram for Fe2+ / Fe3+ in the presence of a solid phase
Lecture 12: Chemistry of Iron, Iron in groundwater, Kinetics of oxidation of Fe2+
Lecture 13: The chemistry of chlorine, chlorine species equilibria, reactions of chlorine species with inorganic species
Lecture 14: The reaction of chlorine with organic substances , with organic molecules containing N , reactions with phenols, trihalomethanes, reactions of oxidation
Exercise 4 (3 hours): Determination of chlorine in water and diagram of chlorine species on the basis of experimental data.
Lecture 15: Biologically important redox equations, nitrogen cycle, redox systems with micro-organisms, microbiological yield
Seminar 8 (1 hour): pc - pe diagram for cT,N = 10-3 mol dm -3 in equilibrium with nitrogen ( pN2 = 0.77 atm)

Format of instruction:

Student responsibilities


Screening student work (name the proportion of ECTS credits for eachactivity so that the total number of ECTS credits is equal to the ECTS value of the course):

Class attendance




Practical training


Experimental work








Seminar essay






Oral exam




Written exam






Grading and evaluating student work in class and at the final exam

During semester two exams will be performed. Final examinations will be administered during formal examination periods. The following percentage equivalents apply to final grade: <55% Failure; 56%-66% (2); 67%-78% (3); 79%-90% (4);> 90% (5). After written exam, student will attend to oral exam. Lecturers do not give grades. Students earn grades.

Required literature (available in the library and via other media)


Number of copies in the library

Availability via other media

V.L. Snoeyink, D. Jenkins, Water Chemistry, Wiley, New York, 1980.


M. Buzuk, Kemija voda (u pripremi), Kemijsko-tehnološki fakultet, Split, 201X


Vježbe iz Kemije voda (interna skripta u pripremi), Kemijsko-tehnološki fakultet, Split, 201X


Optional literature (at the time of submission of study programme proposal)

W. Stumm, J.J. Morgan, Aquatic Chemistry, Chemical Equillibria and Rates in Natural Waters, 3. izd., Wiley-Interscience, New York, 1996.

Quality assurance methods that ensure the acquisition of exit competences


Other (as the proposer wishes to add)