In this experiment we'll show experimentally and following the scientific method that chemicals and pollutants that we throw into the water can affect the plants' growth.

For our experiment we'll use grass seeds. Some of them will be our control test and will be watered with Viladrau water every two days for two weeks. Others will be watered with a solution of water and salt at different concentrations and some others with different concentrations of water and vinegar.

Any idea of what will happen? Can you predict what wil happen to the seeds? Do you expect them to germinate in all cases? 

Your predictions are what scientists call HYPOTHESIS