LESSON PLANSubjects: Biology&English

Topic: Research on the quality of water

Lesson aims.General aim: Students get to know simple ways of testing water quality.Operational aims: A student: gets to know the properties of water environment, develops the ability of analysis of conducted field researches, develops the ability of insightful observation and draws conclusions, develops the ability of logical and analytical thinking, develops his science interests, introduces himself into self-research work, improves the skills of presenting the results of conducted observations and proper drawing of conclusions, states the level of water pollution based on the oxygenation of water reservoir (temperature and turbidity of water), reaction and water scent, gets to know the methods of finding out the types of pollutants found in water, is able to conduct the test of water quality with simple methods, is able to evaluate the state of water in a given water reservoir, understands the risks of using polluted water,

Didactic resources:A beaker, a thermometer, litmus paper, worksheets for the groups of students.

Methods of teaching:Research, group work, an observation, a causerie, scanning and skimming the text.

Lesson outline:1. The beginning: giving reasons for excursion, grouping students, distributing worksheets and research gear.2. The main part: conducting a test of water reservoir according to the tips written in the worksheets,WORKSHEET ATesting the quality of water based on the oxygenation of water reservoir (temperature and turbidity of water)1. Measure the temperature of water in a given water reservoir and write it down in your worksheet.2. Having in mind the temperature of water try to find out the level of oxygenation.3. Take water samples and determine its turbidity. Write down the results in your worksheet.4. Based on your knowledge and an enclosed text try to determine the oxygenation level.

AUXILIARY MATERIAL1. TemperatureThe water temperature has a strong influence on the coexistence of aquatic organisms and physical, chemical and biological processes occurring in water. The increase in temperature causes a reduction of the amount of dissolved oxygen which in turn leads to a deficit of oxygen in water. Increased temperature also increases the toxicity of many substances. Permissible temperature of surface water in Poland is 22 C for the first class of water, 26 C for the second and third classes.2. A turbidity of waterA turbidity of water is conditioned by the presence of undissolved particles of the inorganic and organic origin that scatter and absorb rays of light. Water with high turbidity becomes warmer (particulates absorb light), and by hampering the penetration of solar radiation they reduce the photosynthesis. The turbidity assessment is essential for the evaluation of drinking water for commercial and industrial purposes. The water turbidity primarily affects the look and taste of water. Turbid water is not suitable for drinking and economic purposes.WORKSHEET BTesting the quality of water - its reaction and scent1. Take a water sample into a beaker and smell it.2. Using the table specify the type and intensity of a scent and write down the results in a worksheet. On the basis of the conducted researches try to determine the class of water purity in a given water reservoir.3. Use litmus paper to test the pH of the water sample. Write the result down in a worksheet.4. Determine the reaction of water and on this basis determine the quality of water in the tested water reservoir. You can use the pH scale to help you with your researches.AUXILIARY MATERIAL1. The scent

2. The reaction (pH)The pH of the natural water ranges from 4 - 9 and depends on many factors. The pH of water is important for living organisms, the biochemical processes and for industrial purposes. When reaction is too acidic or too basic a biological life cannot survive. The low pH of water accelerates the elution of heavy metals from the river bed. Acidic waters are of corrosive properties. The basic reaction is caused by anaerobic decomposition of organic compounds with the separation of amines and ammonia or as a result of the discharge of sewage from tannery, for example.A litmus paper as the pH indicatorThe acidic solution turns the litmus paper red (pH less than 5), the basic solution turns the litmus paper blue (pH higher than 8), the neutral solution turns the litmus paper yellow (pH = 7).3. Final part: evaluation of students' work,

Source:Klub Gaja Zaadoptuj rzek Scenariusze zaj do lekcji Biologiiwww.zaadoptujrzeke.pl 7Bibliography:Useful links and bibliography:- indicatorshttp://www.wlin.pl/rola-wody/mapa/09-klasy-czystosci-wody-i-organizmy-wskaznikowe/http://www.wlin.pl/rola-wody/mapa/11-fauna-stawu-plazy-i-gady/http://www.wlin.pl/rola-wody/mapa/12-fauna-stawu-pajaki-i-owady/http://www.weare.pl/mag/r%C3%B3%C5%BCnorodno%C5%9B%C4%87-organizm%C3%B3w-wska%C5%BAnikowych-w-ekosystemach-wodnych wicej