Gas behavior and how that affects our lungs

You will start your first lesson by reviewing gases vs. liquids and solids. You assign the following document as a bellringer, and once your students are given plenty of time to review you make a few statements on the main differences between gases, liquids and solids. (please write at least 3 differences on a word document as if you are addressing a classroom). 

   Bellringer document:  https://www.chem.purdue.edu/gchelp/liquids/character.html

   Task 1: read over document and write three main differences between gases, liquids, and solids on a word document.

 You are immediately asked a question: 

    Josh says, How come gases do not connect to each other the way solids and liquids do? 

After telling josh what a great observation this is, you refer the class to the following animation to show the differences in intermolecular forces: https://teachchemistry.org/classroom-resources/intermolecular-forces-2020 

This only helps the students see the intermolecular forces, to explain why they differ in solids, liquids, and gases. you will need to explain the temperature differences in all three. 

Task 2: read the beginning of this article to explain (in word doc) to the students why gases (have higher temperatures and therefore greater kinetic energy) have looser intermolecular forces: https://www.chemicool.com/definition/temperature.html 

Once you explain to the students, that the gas particles move more and therefore connect less, you move onto explaining how gases move from high concentration to low concentration. it is time to introduce a new term: diffusion.

    Task 3: In your word document, define diffusion. You will need to use the link for diffusion simulation to explain the process to the students. After observing the gas particles before and after you remove the barrier in the simulation, you will need to explain what is happening and why. Also change the temperature and explain what you see and provide an explanation for your students.   https://lab.concord.org/embeddable.html#interactives/sam/diffusion/2-temperature.json 

Once the students understand that gas particles will move from high to low concentration, you explain to them that this is also what happens in the lungs! When your lungs inhale, the oxygen in your lungs becomes a highly concentrated area compared to the oxygen in your blood that's running near your lung cavity. This stimulates diffusion of the oxygen into your bloodstream. In the reverse direction moves your carbon dioxide. Your body creates waste CO2 that is in high concentration in your bloodstream returning to your lungs and in low concentration in the air you just inhaled. Therefore, your body releases the CO2 and absorbs the O2.

    After this explanation, your students are still very confused. Like a good teacher should, you recognize the baffled look on their faces and decide to draw the process out with colors and arrows to better visualize the exchange. 

    Task 4: Illustrate this gas exchange as if you are introducing it to your class. You may do this on paper and take a picture and attach the picture to the word document. (take a photo of your illustration, send it to your computer via airdrop or email, save to your computer, insert image into word document) 

After they grasp the concept of diffusion, you ask them why they think the body inhales and exhales.  

    Of course you are very positive and encouraging as they give their reasoning, and maybe one student even gets close to the answer. After a few answers, you redirect their attention to the video. But first, you ask the students to write down what happens to the size of the lungs when you inhale and again when you exhale.

    Task 5:

    The video: https://youtu.be/8NUxvJS-_0k 

    In the word document: you do the same: explain what happens when you inhale and again when you exhale 

    As well, use Boyle's law to explain what happens to the pressure inside your lungs when the volume of your lungs increase. This video will help: https://youtu.be/q6-oyxnkZC0 

    Last but not least, put it all together, why would air enter your lungs due to the pressure and volume changes. Remember gases move from an area of high concentration to low concentration: if you are inhaling, the volume increases causing the pressure in the lungs to decrease beneath that outside out body. Just as gases travel from high concentration to low concentration, they also move from high pressure to low. 

Task 6: Put it all together, create a summative paragraph about 5 sentences that explain the behavior of gases and how the lungs inhale and how that gas travels into our blood.