Compare the pH of treated city water versus untreated well water. The city water department adds chemicals, like fluoride and chloride, to the water to kill germs and protect your teeth. But the chemicals also alter the pH of the water. Well water, while untreated, is not pure water often containing minerals such as sulfur and iron. Obtain water from at least two wells and city water from two locations. Dip a fresh strip of pH paper into each container of water. Use the pH color guide to get the pH of the samples. Record that information in your notebook. Compare the pH of the four samples.
Compare the freeze time of two types of water. Before starting, state what you believe will happen. Mix 1 tbsp. of salt into 1 cup of water. Measure 1/2 cup of salt water into one cup and 1/2 cup of tap water into another cup. Mark the cups and put them into the freezer. Check every 30 minutes to see when you start to see ice on the top. Record the progress of the two cups of water until both are completely frozen. Was your theory right?
Determine if adding salt to distilled water changes the boiling point temperature. Write down what you think will happen before you start. Boil 1 cup of distilled water on the stove and take the temperature. Throw that water out. Mix 1 tsp. of salt into 1 cup of distilled water and bring to a boil; record the temperature. Get rid of the water again, and rinse the pot of any salt on the sides. Add one tbsp. of salt to a cup of distilled water and boil; measure the temperature. Did the salt affect the temperature at which the water began to biol?
Test whether the type of water affects seed sprouting by soaking lima beans in tap water, distilled water and salt water. Mix the salt water by adding 1 tbsp. of salt to a cup of water. Put 10 lima beans in each labeled cup to sit overnight. The next day, remove the lima beans and wrap them in a paper towel. Put the paper towel into a plastic bag and pour just enough of the liquid from the cup into the bag to soak the paper towel. Check the lima beans each day for a week. Record any that have sprouted that day and remove them from the paper towel. At the end you will only have beans that didn't sprout. Did the kind of water make a difference in whether the lima beans sprouted?