With all this figuring out happening, we turned back to our Driving Question Board to answer all the questions we had from the launch of our unit! Look at how far we've come!
Mrs. Brinza also challenged the sixth graders to redesigning a cup with any features they felt would help slow energy transfer. Since we were in a combination of hyrbid and remote, we did the challenge on a day where everyone was remote! Students had to put ice in their redesigned cups at the start of class, and if anyone was successful with ice in their redesigned cups by 3pm when school got out, Mrs. Brinza would pie herself! Based on the pic below, do you think some of the students were successful? I think so! Way to go 6th graders!
We've figured out so much since we launched our unit months ago, now having a much greater sense of why a fancy cup works better than a regular cup at keeping something cold! We had a great discussion and came to consensus! When we first started, we didn't even consider particles, energy transfer, or collisions! Look how far we've come!
Now that we've seen what gas particles are doing as they collide, we're wondering what they're doing in solids, since the cups themselves are an important part of what may be keeping a drink hot or cold in a fancy cup!
Here are some big ideas we figured out!
1. Heat still transfers in solids!
2. When there are more points of contact, the energy transfers quicker.
3. When a solid is smaller, but hotter, it still transfers energy to a colder, bigger solid; however, the overall temperature change is minimal.
4. When a solid is bigger, but hotter, it transfers energy to a colder, yet smaller solid really quickly!
We're putting all these ideas into action! Collisions are happening everywhere! Energy is being transfered everywhere!
With all these ideas emerging as to what particles "really" do, we are recognizing that drawing them 2-dimensionally doesn't give us the full picture. We're turned to some computer based models alongside the work of famous scientists (James Joule being one of them) to help us understand the relationship between temperature, particle motion, and energy. We're using a new simulator that is helping us see so many new things!
Here's what we've seen so far!
1. Increasing the initial temperature of the gas makes the particles move faster.
2. All the particles in the gas don't move at the same speed...some move really fast and others more really slowly!
3. When a fast particle hits a slower particle, the fast particle slows down and the slow particle speeds up (kind of like in a car crash with a parked car).
4. Even though particles are constantly speeding up and slowing down, the overall temperature stays the same.
5. When you add more particles and keep the temperature the same, we see an increase in energy. This is making sense to us as every particle has energy...so more particles means more energy!
We continue to use the simulator to help us figure out what's going on with our cups to make our hot drinks cool down and our cold drinks warm up!
We're starting to think there's movement/energy in the liquids after we watched the peppermint candy dissolve in all temperatures of water. So we agreed to add to some food coloring to different temperatures of water and watch what happened!
After thoughtful discussion, we agreed that energy couldn't be represented as a particle, since it doesn't have mass and doesn't take up any space. Therefore, we ruled out the ideas from the blue model. The green model had a line for energy, which was better than a particle-shaped idea, but we really couldn't tell the difference between the size of the lines, and we know there should be some difference in quantity since the hot liquid moved the food coloring faster than the cold liquid. Therefore, we ruled on either the purple model or the red model, which quantified energy in terms of size.
One thing we realized though, was that we had a question--does every particle have energy? Or just some? So we turned to a simulator to help us with our thinking, and it really helped! Indeed, every particle has energy and is moving. Hotter liquids have more kinetic energy and cooler liquid have less.
From here, we thought we could come to consensus on what the particles look like at different temperatures! All this digging deep will really help us consider what exactly causes our warm liquids to cool down and our cool liquids to warm up! What does the air look like compared to the water? How does cool air around a hot liquid get it to cool down? Or warm air around a cool liquid get it to warm up?
Recognizing a bunch of patterns from our water bath experiments, we are recognizing the power of how a model can help us understand what is going on with both both hot and cold water when they are near each other.
In order to do this, we first have to figure out what hot things and cold things actually look like on the molecular level, so we had some class discussions about each of the models below.
Thinking about what hot and cold things "do" really got us thinking. We know that hot things cool down over time, and that cold things warm up, too. So we're trying to think about what the particles/molecules are really up to. How is it that they get more or less energy over time? We turned to YouTube for some guidance to consider what happens when we begin to "SEE" what's going on with things that really are oh so tiny!
We saw that the candy in the hot liquid began to melt/dissolve/remove the red coloring faster than when the candy was placed in the cold water. But it was so interesting to see that even in the cold water, the red part of the candy came off. We know that the only way something can come off of something else is with force. So is the water in the cups really moving? And knocking on the candy? We really wished we could zoom in on the water to see what it was doing!
So with our hot and cold water baths finished, we looked for patterns with what was going on, filling out the Jamboard together as a class. We're obviously seeing that heat can transfer between the walls of the cup, and we're starting to connect this with what the particles in the cup will actually look like when they're hot or cold!
So we really wanted to change the air temperature around the cups, but there were just too many variables involved. So we agreed that we could surround the cups with a water bath as a good replacement and see what would happen. We ran the experiment remotely with Mrs. Brinza collecting data and some students took on the challenge. Here's what we got!
Thinking about the air's role around the cups, we revisted our investigation ideas chart to see what we thought we could do to figure out how heat, or hot/cold air could maybe play a role in warming up the cups that weren't in light.
We had an idea to change the air temperature around a cup, either making it really hot or really cold. We could do with a hair dryer or a heater, or in the case of giving a cup access to cold air, we could go outside. There were a few problems with our ideas.
1. The air warmed up by a hair dryer or a heater wouldn't be consistent and no matter where we'd do this in our houses, the room would be too big to "enclose" the air and we'd get big differences in air temperature around the cups.
2. It was a whopping 3 degrees Farenheit this morning here in Chicago, so while this would give us cold air around our cups, that's just too cold for us to do our investigation outside!
We we thought of another idea...to use water around the cups instead of air. It would be easier to contain in a container, and we could easily heat up and cool down water at our homes (either in the microwave or by adding ice)! We made some predictions to close out class before we run the investigation tomorrow!
With all our data collection, it was important for us to sit down and actually try and make sense of it. We had data on how the light was interacting with each of the cups and it was helpful for us to see what the data meant in other types of models!
By looking at the percentages of light that either reflected, transmitted, or had been absorbed by the cups, we were starting to see what was really going on with the cups! We also took all this data analysis and connected it back to the first model above, as we could now quantify how light was interacting with the cups differently!
Looking at our models made us do some new wondering. If the light can transmit into the cup, then it would make sense it's transforming into heat and warming up the liquid. Any light that would reflect off wouldn't reach the liquid, so it wouldn't warm up from reflected light.
But we're really stumped on the light that gets "stuck" or absorbed into the walls of specific cups. This light never made it into the liquid, so how does light that's absorbed heat up the liquid itself? The walls are next to the liquid...
We're gonna table this idea since it seems kinda tricky, and revisit heat energy that we think also plays a role in rising temperatures of the cups. This is especially true since the cups that were in no light also warmed up! But how?