BECOMING A CHEMIST!
|Igniting Curiosity through the power of observation.|
Last week students spent time in the science lab testing a variety of materials (salt, sand, oil, and an Alka-Seltzer tablet) to see what happens when they are mixed with water: what dissolves, what reacts and what remains unaffected.
Students hypothesized what they thought would happen based on what they already knew about each of the materials. While conducting each test, students captured their observations in words, images and videos. As you could imagine, the lab was buzzing with excitement, students eagerly calling their teacher over, wanting to share what they had observed, attempting to explain the science behind what happened.
Back in the classroom, students shared what their group observed for each test and their wonders. For example, many students wanted to know why the salt appeared to "disappear" when they stirred it with the water. Others wanted to know why the oil "floated" on the water or why the sand "sank to the bottom" and would not "mix" with the water. The overwhelming wonder each class shared was, "what caused the Alka-Seltzer to fizz in the water?" Using their iPads, students were now driven to deepen their scientific understanding by researching the science behind what happened with each test. This gave each student the confidence to speak like a "real chemists."
Now that students where beginning to feel like chemists their final task was to create a method to separate one of the materials from the water. Using their creativity and knowledge, groups worked together to develop a method and list of materials needed to accomplish this task. Prior to going back in the lab groups shared their method with their peers to receive feedback. Based on the feedback, some groups needed to adjust their method or complete further research, calling on the expertise of their peers.
Throughout this scientific process of separating the materials from the water, students discovered: that when a solid material dissolves, it can be recovered as a crystal by evaporating the liquid; you can always get the sand out of the water by filtering the water away; oil and water are two liquids that are immiscible – they will not mix together; and that when two materials react to form a new material, the original materials cannot be recovered because a chemical change has occurred.