Salty Solutions Objective Students will learn a method to measure salt content in water. Other solids include sulfate, magnesium, calcium, and potassium. Tidal marshes, wetlands, and estuaries have varying salinity values depending on the addition of fresh water. Action Divide students into four groups and give each a soda bottle. Fill bottles with water.
Students weigh bottles and record their findings.
Three groups add salt to their bottles to create different salinities. Stir until all the salt dissolves. Mark water levels on bottles with waterproof markers. Use the hydrometer to chart the readings for these four solutions. Students can create their own tables or fill in data in the Salty Solutions Reading table at the bottom of this page.