Discover the pH value of:
drinking water, rain water, water in rives, and mineral water.
Equipment and materials
pH indicator solution
pH color chart
1. Pour the water sample into the test tube to a height of approx. 4 cm.
2. Add 4 drops of pH indicator solution and swirl the test tube. Compare the color with the color chart.
Drinking water usually has pH 7. If drinking water is acidic (pH 5/6), this indicates dissolved carbon dioxide. The same result is obtained for mineral water containing carbon dioxide. If the pH value for rainwater is less than 7, you have found evidence of “acid rain” and the indirect pollution of the air with acid-forming exhaust fumes. Acid water can also be regularly found in marshy river. Weakly alkaline drinking water come from limestone areas. Strongly alkaline water is only to be expected in the case of pollution with soaps or similar detergents.