 Hey, you guys, so I thought I would record a quick video going over the data table from the potato lab because it looks like From the lab discussion that there's some confusion and when I sat down to look at this data table and go, okay What what's what's the difficulty here? Why are we having a hard time? There's a significant typo in this data table that is super confusing. So first I apologize for the typo second pretty much every group of students I've ever had does something new in my classes and serves as a guinea pig for the future and you are benefiting from a lot of things that other students were guinea pigs for in a lot of ways But you are being the guinea pigs in these Carolina labs. So For the most part, I'm feeling pretty good about them, but we're definitely finding some issues Anyway, so when I went in to take a look at okay, what's the scoop here? The typo that I found that I think is significant is this puppy right here. Oh, that's really big and We can't have a pen size like that, but this is the okay, whatever dude. We're going with that pen size It doesn't make sense to be dealing with length times width when you're cutting your Your whatever potato in half because you cut the length of your potato in half, right? Do you know what I'm talking about here? Okay, there we go. So when you have your potato Here's your little boxy potato, right? if you think about it Where you label the length or the width of the height depends on how you set your potato on your table so don't like Who cares you the only thing that matters is that you are consistent and that you follow their Directions, so the way that they're explaining it if this is the face of the potato looking at you We'll throw some little smiley faces on there if that potatoes taken a look at you that way They're calling the length this side like heading away from you. They're calling the I got a width the little That makes sense to me the wide part and then they're calling the height the part that's up and down Did you follow what I just said? I'm not sure anybody did When you do your cross-section what they're asking you to do is to cut the length in half So you start out with a length at 2.5 For this particular potato chunk you're gonna end with a length after you cut it that length is gonna be in Half, so it'll be 1.25. This one will be one. This will be 0.75 right this will be 0.5. This will be one. This will be 0.25 Now I've been hearing a lot of like I've been measuring my potatoes and it took me five hours to measure my potatoes Please be nice to yourself and if your measurements aren't Exactly precisely accurate like do the best you can and maybe report out like I'm not positive about my measurements but the actual size I think we'll still get the point even if you don't have your Measurements perfect, so be nice like move on. It's all part of having a good time. However If you're gonna find the cross-section of your potato All you do is you're gonna multiply the height time. There's a little width. That's correct So you're just gonna go through and here's my height Here's my height there's my height and Here her Her my width so there's my width so I'm gonna end up with 2.5 times that's the times Whatever 2.5 You do that math you're gonna get a number That little number is gonna go right here. That's the size of your cross-section. It's an area. That's what you're calculating You know what when I go through I'm gonna redo these instructions for the future classes And we'll call that the area because that's what it is. I think that would make it a little more clear Okay, so you get the area of the cross-section The distance that the icky traveled is actually a length like that It's not an area. It's just a distance and so you can imagine That if this is my cross-section you all had icky You had black come in and that black is iodine combining with starch in the potato so What you're gonna measure at this point and man my pen is awfully large for this activity But you're gonna measure that chunk right there. That's a width and again Really, it should be the same You drop a huge potato in to the icky solution and Diffusion lets the iodine diffuse into that potato Bind with starch in the potatoes starch is a carbohydrate and Change it to black. You can see how much diffusion happened by how far in that icky diffused If my potato is one pound or 50 pounds In the same amount of time The icky should diffuse in the same distance if all other factors are the same So for all of these guys the distance traveled by the icky should be about the same So I don't know what your numbers are, but this let's just call it x It really should be about x. There'll be some variation, but it should be about x for all of them The funky part is the fact that they asked us when they asked us for the area of the white region They asked they said length times width and and so think about this And I know since you've done this already this will be clear But here's your block of potato that was sitting in the icky So diffusion happened and there's a it's black when you take it out of the solution You've got this black potato chunk You cut it in half length wise. So now my lengths are half you open it up and Voila, there's like this really cool Line of black and then the inside potato is white, but the face that you're looking at is Length I mean width times height So the length is going this way, and I'm sure that that was your confusion So the area of the white region is just saying okay when you do your cross section and you see this The fact is that this is what width and height Cut on that in line, right? Do you see that and then what you're measuring is this height Times this width Not the full height times width, but just the white part So this should be the area of the white region should be changed to height times width of the White part just the white part white that says So once you get that one done Your challenge with table B, and I'm gonna actually leave table a here so that we can just see it down here Table B you're transferring a bunch of information directly to Table B, and it's not confusing. So the surface area of my slice With times height is just this column right here Right, that's the slice that you so you're taking the data. This is my raw data table raw and Then this is my manipulated That whatever I'm not manipulated My manipulated data table is just the place where I'm compiling like the take home messages so The length okay, so we've got that the surface area of the white section you've already calculated that as well The surface area of the black section. This is gonna be you're gonna have to think this through for a second The surface area of the black section is gonna be calculated. I don't know how you want to do it But you might do something like this You would probably have two of these and Then something like this Just a minute That person is gonna have to wait. So pardon the telephone call Okay, so then you're gonna calculate Whatever multiply length times width here height times width for each one of these black strips And then add those together and that's gonna be the surface area of the black section Do you follow that? So that one's gonna be a little bit of Extra work, but here all you're gonna do is you're gonna take the surface area of the black section which was right here and Divide it by the surface area of the slice Which was right here So you're you're getting numbers that you can then look at and see like hmm is this Are these numbers significant? The surface area to okay. All right, so the surface area of the whole block Here it tells you how to do this and again, I would just plug your numbers I had to think about it length times width times two and width times height times four like Okay, um, I just trust it the numbers that you have for length and width and height just trust those You've got them in here Just plug them in and that will give you the surface area of your block to calculate your volume Multiply all those guys. You don't have to do any Experiment to calculate these two piece these two columns Once you have these two the surface area to volume ratio is also easy to figure out this lab this activity right here is really good and It's if you can think through What's going on with what with the data that you're collecting? I think you'll be really glad that you did it Okay, I'm gonna go find out who's calling me all these times and Hopefully that is helpful and let me know if it isn't And you will huh, okay, I love you