September 1 We had our first ever Lab Experiment today, which was creating a substance called Ooblek. Pre-Lab Beforehand we had a lesson on mass and it's three different forms. The three forms were solid, liquid, and gas.
Materials
Since I knew water was being involved, I imagined that the corn starch would mix in with the water and would become a sort of watery "batter like" substance. I didn't expect the corn starch to act far differently than how flour would when mixed with water. I honestly thought that the form would stay on the majority of the liquid side. We were told that the lab was going to be "messy" so I thought that the water aspect of the experiment was going to make it very messy. ____________________________________________________________________________________________________ What Happened? - An Oobleck Story I worked with Kazuha, Sammie, Melany, Natalie, and Ash. We got our beaker of water and our corn starch. At first we were hesitant to pour so much water in, we thought that the corn starch would lose its form. But we were surprised as the water we poured in felt like it was absorbed right into the corn starch. The corn starch was only getting a little damp as we added in water. We then poured the whole beaker of water in the corn starch. After putting in so much water I expected the corn starch to slowly and finally dissolve into the "smooth cake batter" consistency like flour would. But to all of our surprise, no matter how much our fingers mixed the corn starch, it had stayed at the bottom of the bowl under the large amount of water we put in. My table mates piped up saying things like "Guys it's not working" , or "move your hand you're not mixing it right!" or "Aw it's been five minutes and we already ruined it." In confusion we looked at the other tables, we watched as they got their whole hand dirty trying to mix the oobleck. We went back and did the same. We mixed and mixed until the form (consistency) smoothed out. Even after we mixed I noticed that the water kept drying and leaving the corn starch not moist at all. I panicked, almost about to dump more water into the bowl, but then Brayden came over and showed us something that literally blew my mind. I watched in awe as he picked up the bowl filled with (what I thought) was dry oobleck. He began to tip it, and in my mind I thought the oobleck would just fall onto the table like a sad pancake. But to my surprise as he raked the oobleck out of the bowl, it became to pour down like a waterfall onto the table. Not knowing ho w to comprehend how the oobleck changed its state, I moved onto another problem. I began to panic again as the oobleck fell onto the table, I thought we would create a huge mess and that the oobleck would seep through the cracks of the table and fall into a big puddle mess onto the floor. I almost ran to get paper towels when Andrew came up and blew up my mind again. He said "watch this" and quickly swept his hands across the table where a pile of oobleck was, The ooblek obediently scraped off from the table and rolled into his hands, he placed it back into the bowl safely. Dumbfounded, I immediately grabbed the bowl and poured it our on the table again. We all played with the oobleck, watching happily as it changed between solid and liquid form. After awhile, some oobleck dried onto the tips of my fingers. But as I touched the bowl full of liquid form oobleck, the dried coat on my hand slowly formed with it. At one point, Brayden came with a hammer. He got our bowl and told us to watch. He hammered hard into the bowl. The oobleck didn't splash in our faces like I would have thought it would. It just withstood the force of the hammer. AS IF IT WERE A SOLID! That got me thinking about how pressure affects the ooblecks state of mass. As he pulled out the hammer, it was clean as if he had never touched it with the oobleck. I noticed how when I dipped my finger slowly into the oobleck, it coated my finger like paint, but when I put more pressure into the oobleck it stayed in a solid form, not leaving a mark or trace on my hand. This and many other things surprised me. It was indeed messy experiment. But was very enjoyable and mind blowing for me. What I learned? noticed?
Liquid? Solid? What form of mass? I feel like this is highly debatable. Oobleck can take both the form of solid and liquid. Although on my opinion, I believe the Oobleck is a liquid that just reacts differently when manipulated. If you don't do anything to the oobleck, it remains a liquid. But it is only when you manipulate, move, put pressure on this liquid that it changes forms into a solid. I feel like at its base it is a liquid. A solid has a definite volume and definite shape, and the molecules shouldn't be able to move at all like Oobleck does.. I don't define Oobleck as something that is for sure a solid. I feel like it's a liquid that can respond to certain conditions to then turn into a solid. Oobleck is first a liquid when you make it, it isn't until you abruptly move that liquid that it changes into a solid. Molecular level explanation: I'm not sure exactly what is happening on a molecular level but I'll say these ideas anyway. Oobleck reminds me of snow. Slow is sometimes soft to make snow angels and to slide down on sleds. And in some cases you can sink your winter boots into snow as if pushing it down with your feet. BUT, in other cases, when we have snowball fights, snow doesn't become the same soft snow we roll around in. In all cartoons and in real life experiences as well, we pat down the snow ball, adding more snow to it while doing so. And all of the sudden, when pressure and impact is being put to the snow, the snow grows harder. We fling these now "hardened" snowballs at our friends and family and watch as they hit very hard on impact. It is almost like Oobleck. When the corn starch molecules or particles (or whatever they are referred to) are pushed together, the create a hard substance. The molecules are pushed closely and tightly together, becoming a solid. The molecules in solids are not able to move around due to being so compact. So the form of the oobleck and snow mimics that. The molecules are no longer able to move around, forces like impact or pressure and pushing the molecules closer together to create a solid form. Snow is almost considered "soft" until we smash our bodies into it and make it into solids. My theory: My theory is that Oobleck is indeed a solid. People may perceive it as a solid but I think the corn starch molecules are just able to mimic a solid form when manipulated. When mixed with water and left untouched, Oobleck is indeed a solid that can leave off a trace on your fingers once dipped in. But once the corn starch molecules are put under forces of pressure such as impact, pressure, or abrupt movement, the space between the molecules grows smaller and more compact, as would a solid's molecules. The oobleck responds to pressure and becomes a strong solid, able to withstand impact due to the temporary placement of molecules. Once oobleck is manipulated, it can change into a solid. It is a liquid that responds to impact by molecular turning into a solid form. The photo below shows how dirty this experiment really was. As you can see, there are scrape marks on the table, that was when we were able to quickly swipe off the oobleck with our hands to put back in the bowl. The video after it shows the hammer hitting the oobleck, showing the force that keeps the oobleck in solid form. "What would happen if that was a liquid?" - "It would go everywhere and splash."
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