The author explains a virtual chemistry lab activity for use in a high school chemistry class. This activity is an excellent way to introduce measurements, significant figures, and the concept of density.
As high school teachers, we know that understanding how measurement works is crucial for lab skills and for understanding significant figures. We think measurement should be an easy topic for students to learn; especially because we know that teachers begin working with students in elementary school to teach these skills. However, I, and many other teachers, have spent countless hours teaching and reteaching a seemingly simple skill.
It can be difficult to engage students in reviewing for semester exams by using worksheets or practicing problems on the whiteboard. If you are looking to change up your review plans, you might consider using a lab activity that provides opportunity to revisit many of the topics that need to be covered.
As I began to prepare my labs for this upcoming year, I decided to put a bit of a twist on a previous density of a block lab I had used in the past entitled the Measurement Challenge that is sold by Flinn Scientific. It can also be used to find the mass of a block given the materials density and requiring students to measure and calculate the blocks volume. My added twist resulted in great scientific discourse.
If you are looking for a measuring and density activity that will be challenging, allow students to experience success early on and can be boxed up to use again, you might consider trying the activity that I am sharing in this post.
I want to share a measuring activity for you to consider. First, start with two baseballs. The first baseball is a regular baseball. The other baseball is called a "small ball". Next, get six to eight students to volunteer. Without talking at all the students must hold the normal baseball and the small ball. They then must decide if the normal ball has more, less or the same mass as the small ball.
My first experiment involves measuring the density of water. Each group of two kids is assigned a specific volume of water from 10 to 100 mLs on the tens. They simply measure the mass of an empty graduated cylinder and then add the water and find the mass again. Once they have their data they go around the room and find another group that has one of the volumes that they need and get the data from them and record their names. Once complete they generate a graph of the data and answer a few simple questions. The whole procedure can be completed in about 20 minutes.
Like most chemistry teachers, one of the first things I go over in the beginning of the year is unit conversions. Students come into my class with all sorts of prior knowledge concerning unit conversions; some good, some bad and some downright ugly.
With the Olympics just finishing up, I was excited to see the following link posted on Twitter entitled: Significant Digits and Pool Tolerances are Why There are So Many Ties
This week I did "The Murky Myster of Matter Measurement" by Chad Bridle. Basically, students are working at making a series of predictions and measurements concerning the mass, volume and ultimately density of two different types of beads.
