1. Projeto Comenius " Life-Giving Water" This project has been funded with support from the European Commission. This publication [communication] reflects the views only of the author, and the Commission cannot be held responsible for any use which may be made of the information contained therein.

2. Escola Secundária de Almeida Garrett Comenius " Life-Giving Water" Water Analysis 3 beakers with different types of water: river water, tap water and rain water: 6 graduate recipient; pH meter dropper Measurement of pH Hardness

3. Escola Secundária de Almeida Garrett Comenius " Life-Giving Water" Water Analysis Water SamplepH Douro river7,01 Tap water8,26 Rain water7,54 Tap water pH values should be 6,0<pH<9,5

4. Escola Secundária de Almeida Garrett Comenius " Life-Giving Water" Water Analysis Hard waters are generally considered to be those waters that require considerable amounts of soap to produce a foam The soap-consuming capacity is most important because of economic aspects and because of the difficulty encountered in obtaining suitable conditions for optimum cleansing.

5. Escola Secundária de Almeida Garrett Comenius " Life-Giving Water" Water Analysis Water SampleNumber Douro river1 Tap water2 Rain water3

6. Escola Secundária de Almeida Garrett Comenius " Life-Giving Water" Water Analysis Hard waters Average hardness Soft waters