Teaching students about the properties of water is an essential topic in my biology class. Students know that water is an important molecule and is necessary for life, but they aren’t sure why. Typically, students know that you can’t live without water in your body. But when it comes to having a deeper understanding about the atomic structure of water and how it relates to the specific properties of water, students will need some guidance. Here are 5 activities you can use to teach the properties of water during your chemistry of life unit that will strengthen student understanding and prepare them for future topics in your class.
Introduce Why Water Is A Polar Molecule
Before going into detail about the properties of water, it’s best to start with the atomic structure and explain why water is a polar molecule. Since most kids will know water as “H20” it’s a good place to start with the 2 hydrogen atoms bonding to an oxygen atom. From here you can discuss the unequal sharing of electrons which gives water its partial positive region and its partial negative region.
In my chemistry of life lecture notes I like to use pictures to help illustrate this. I have a few sides I use in succession. First I begin with a single water molecule and explain why one side is partially negative while the other side is partially positive. From there I will show a slide that has multiple water molecules on it and explain how hydrogen bonding can connect them (we have already reviewed covalent and ionic bonds by this time so bonding is a subject they have recently seen). Finally, I will show a side of a water molecule attracted to another molecule. When we discuss water’s role as the solvent of life, we can refer to this slide and how many molecules will dissolve into water.
What Are The Properties Of Water?
After teaching the structure of water I continue with a brief summary of what are the properties of water. Again, I would recommend breaking up lecture slides with plenty of pictures to help students get a better grasp on the content. For example, when covering cohesion and adhesion, I like to use the example of water traveling from the roots to the leaves of plants. For surface tension, pictures of tiny insects walking on water can help with student understanding. And for specific heat I use both the boiling of water and the example of coastal temperatures staying more constatnt than inland temperatures .
Review With A Properties Of Water Video
Once we have gone through a short lecture on the structure of water, I like to reinforce the topic with a short video. Many kids struggle with processing information when presented only in lecture, so using a video or another method of teaching will complement what was just covered. The properties of water amoeba sisters video is a great way to build on what was just taught. If you haven’t seen it on YouTube, I would recommend checking it out. I initially thought it would be too basic for my freshman students, but it is well designed and can be shown in smaller segments or as a single video activity. The whole video is just 6:50 long.
Check For Understanding With A Properties Of Water Worksheet
Using a properties of water worksheet can be done in class or given as a homework assignment. While there are many options available, two I like are my properties of water doodle notes and my properties of water concept map. I think the doodle notes are a good in class activity which can be used in an interactive notebook as well. I have a few variations of my doodle notes depending on the level of my students and how much support is needed. With the concept map, I will sometimes give it as homework while other times I have used it as a bell ringer to bridge content from one class to the next. I know every school uses a slightly different bell schedule, but at my school we are on an A/B block schedule. This means my students will go a few days between classes and having a bell ringer will help get them back focused on the topic we left off with. To help keep my students organized with my notes, and handouts, I have them use an interactive notebook that will also assist them in studying for future tests and quizzes as well.
Get Students Involved With A Properties Of Water Lab
There are plenty of quick lab activities that you can use to teach the properties of water. For demonstrations I like to use the penny activity to describe surface tension and the movement of a colored die through a celery stalk to teach cohesion/adhesion. If time permits I think doing a pH lab with household items fits well into the curriculum. Teaching students about the properties of water and reviewing acids and bases works well together. And chances are you will be covering pH when discussing enzymes later in your chemistry of life chapter. I have found buying pH paper strips on Amazon to be pretty cheap if your school doesn’t give you much of a supply budget. From there I go to the grocery store and buy the needed household items to complete my acid and base lab.
Finish With A Properties Of Water Quiz
Properties of water is just one part of my larger Chemistry Of Life unit (we are also covering macromolecules and enzymes/chemical reactions) and so I like to do a quick review before going to the next topic. For me a quiz is a great option. In my class I give a lot of quizzes as formative assessments that don’t have a lot of weight on a student’s overall grade. My quizzes are generally 15-20 questions and a mixture of both identify and matching questions. I want to know if the students are getting the content, or if I should spend a little more time reteaching before we move on. My properties of water quiz checks to see if students know the key terms we have covered along with knowing some pictures that illustrate the different properties of water.
Final Thoughts….
While you may only spend a few days teaching your students about the strucure and properties of water, this topic is one that you will refer back to throughout the school year. The properties of water become relevent in teaching ecology, cell membranes and transport, photosynthesis and cellular respiration, and any physiology taught in your curriculum. Hopefully the above ideas will give you some inspration about how you can build out your lessons and improve your student’s understanding of this topic.
