How can I make an abstract concept – one where I may not be able to look at close up – engaging and applicable? For example, the kinetic molecular theory (KMT) is one of the most important concepts for high school students to learn. Demos like adding food colouring to hot and cold water or attaching a balloon to the opening of a flask and then heating the flask can show how particles move faster or further apart when it gets hotter. However, what’s something applicable that a student can do, make, and tinker with when learning about KMT? How can we make an engaging KMT activity and/or lesson?
One way we can make an engaging KMT activity or lesson is to actually make something useful and link it to KMT. We propose making gift card cell phone holders and wine bottle planters. Last year, I made both objects with students in two separate makerspace workshops I led. And, they loved it. We also had parents make gift card cell phone stands at an open house. And, they loved it too. Both gift card cell phone stands and wine bottle planters are useful. Both link to KMT. And, as a bonus, both also link to the idea of sustainability (ie. taking something we normally throw out and reusing it in a useful way). We outline how to make both objects and how it links to KMT. You can also download a template and instructions on how to make the gift card cell phone stands so that you can make some in your classroom too.
KMT and Used Gift cards
What can we do with a used gift card? Make a cell phone stand for it! Students enjoy this activity because it’s simple and quick to do and it produces something useful. Also, if you get a variety of cards, students can make unique stand for themselves.
From a science teacher’s point of view, this activity demonstrates the concept of adding energy to melt an object and removing energy to solidify it again. By applying heat to the gift card, the heat allows the plastic to become more fluid and malleable – so that we can bend it into shape. Then, after removing the heat and allowing it to cool, the card becomes more rigid and holds it’s shape. A video on how to make this cell phone stand is found below:
Although the video shows the use of a butane lighter, our students used regular tea candles and got the same effect (it tool a little longer, but it works).
KMT and Wine Bottles
What happens when extremely extremely hot glass is placed in ice water (or, vice versa – boiling water is poured into extremely cold glass)? Easy, the glass cracks. The uneven expansion or contraction of glass while the glass is cooled or heated up causes the glass to crack. In this KMT activity, we don’t just crack glass – we look to apply this concept to cutting wine bottles in a precise manner.
The craft is fairly simple. The video below shows 3 ways in which bottles can be cut. I will outline how we did it in our class.
First, we start by scoring the bottle with a glass cutting knife. We use a wine bottle cutting tool. Then, we pour boiling water evenly and quickly around the score line. Finally, we submerge the bottle (at least covering the score line) in ice water. The temperature shock will not just shatter the glass, it will actually shatter along the score line. If not, repeat pouring boiling water and submerging the line until it does.
The interesting thing about cutting bottles is not the fact that an even line can be cut on the bottle. Actually, I find the bottles that don’t cut so evenly to be far more interesting. One student of mine – who got really good at cutting bottles evenly – noticed that the boiling water should be poured quickly over the score line so that thermal expansion can occur evenly. If not, the bottle will crack unevenly. And, this happens a lot, which just shows how interesting and complicated thermal expansion can be.
We can illustrate abstract concepts – like KMT (Kinetic molecular theory) – in more concrete ways. And, those ways don’t need fancy, expensive equipment either. By using simple things students may normally throw out and turning them into things of value and usefulness, we can make an engaging KMT activity and show how KMT can be applied in the real world. Click on the link below to join our email list and get a copy of our gift card instructions and template for this KMT activity.
Until next time, keep it REAL.