Most rain has acid, but due to industrialization, gases that are released into the air; these gases form clouds and are sent out in the form of rain. Car exhaust fumes, power plants and factories release gases that contribute to acid rain. Acid rain damages forests, increases acidity in bodies of water and wears away at buildings and statues. Acid rain can wear away at seeds and eggs, which decreases populations of plants and animals; lakes and rivers with high levels of acid harms the plant and animal life that exist in that ecosystem.
Put water in one jar and vinegar (an acid) in another jar. Place a piece of chalk in each jar and let them sit overnight. Look at each jar the next day and observe and record the results; you will notice some erosion of the chalk that was in the jar of vinegar because the acid eats away at the chalk, much like acid rain erodes statues and buildings. Conduct the same experiment with a plant or leaves. Plain tap water is not damaging like the acid. Experiment to see which liquid causes the most erosion of pieces of limestone – hydrochloric acid, vinegar or water. Each of these liquids has as different pH, meaning each has a different level of acidity. Calculate the mass of the limestone before and after erosion.
By fifth grade, students understand the scientific method and should conduct experiments according to the method. First, students ask a research question; for an acid rain experiment, the question could be “how does acid rain damage buildings or ecosystems?” Students should then conduct background research to see what other experiments have been completed; they can model their experiment on a previous one. Students come up with a hypothesis, or a guess as to how things work. For example, a hypothesis for an acid rain project is “If acid rain erodes rocks, then hydrochloric acid and vinegar will erode limestone.” Test the hypothesis by conducting an experiment and record data. Fifth-grade students can do some math, such as calculating the mass of the limestone before and after erosion, and present this data in their report. This report will present their experiment and results, and students will explain if their hypothesis was true and any conclusions that can be drawn from the experiment.
When choosing experiments for a science project, be cognizant of the grade level and a student’s abilities. Studying the effect of different liquids on a piece of chalk or limestone is an appropriate project, and it follows the scientific method. Always ensure students use safety goggles and gloves when working with acid; proper safety habits are necessary for science experiments. Ask fifth-grade students to make a poster or report for their experiment that follows the steps of the scientific method; this step helps students learn about the method, how to properly present scientific data and requires the student to think about their experiment and its importance.