Science+Eureka

Science Eureka During the sabbatical week, I joined the science eureka course. The course is all about science in chemistry, physics and biology. I will be telling you what I did during the 5-day course. I will only be telling you all one experiment that I did each day and I will definitely choose the experiment that I feel is the best for that day. Day 1: For the first day, we were having physics. I will be telling you about one of the experiments we did. Due to the short amount of time we had, we did not finish all the experiments that we were supposed to finish. Experiment: One of the experiments is about the Doppler Effect. We were asked to take a stopwatch with a piece of string tied to the stopwatch and go to an opened space. We were then asked to set an alarm for the stopwatch. One would then hold the stopwatch and swing it when the stopwatch rings. The rest will then stand away from him to hear the watch ringing. What we hear will be the Doppler Effect. It is observed that people standing away from the guy who is swinging the stopwatch will hear a lower pitched sound while people who are standing away from the stopwatch will hear a higher pitched sound. The explanation to this effect is as follows: When you swing the watch around, the watch stays about the same distance from your ears all the time, so its sound waves reach your ears at the same time. However, when you stand back as your friend whirls the watch around, the beeping watch moves away from you, then toward you. When the watch comes closer, the sound waves bunch together, so more waves get to your ear each second. This makes the pitch of the sound go up. As the watch swings away from you, the sound waves stretch out, making them sound lower in pitch. The speed of the sound waves is the same coming or going, but the frequency or pitch changes. Reflection: When I listened to the sound as the stopwatch rings I felt that the sound that I heard was very cool, very interesting, like hearing the sound waves. After listening and also reading through the explanations, I still felt lost as I could not understand some stuff, and I eventually understood them all. This kind of experiments with cool results and process really does spur me to like science. I also like the trainers as they were very kind and would explain nicely if anyone did not understand the explanation text. Day 2 & Day 3: During days 2 & 3, we had chemistry for our science eureka lessons. We fiddled around with different chemicals to observe chemical reaction that will happen. I will be telling you about 2 of the experiments, one from each day. Day 2 Experiment: Rates of Reaction We are asked to investigate the effect of surface area of a solid substance on the rate of a chemical reaction. To investigate on that matter, we were supposed to obtain 4 pieces of magnesium. One is supposed to be left alone, while the others will be cut into 8, 4 and 2 pieces respectively. Then, we were asked to measure 10cm3 of sulfuric acid and pour it into 4 different test tubes. Then add the magnesium into the test tube and start the stopwatch. There should be presence of effervescence (bubbles appearing). The presence of effervescence is caused during the reaction between both substances. Stop the timer only when the bubbles stop appearing. Then record down the time taken for both substances to react fully. After the experiment, our conclusion was: the higher the surface area, the higher the rate of reaction with a certain amount of substance. Explanation: If the surface area of the magnesium were larger, then a larger amount of acid would be in contact with the magnesium at any particular time. This would increase the frequency of collisions between the magnesium and the sulfuric acid, hence increasing the chance of successful collisions. This in turn increases the rate of reaction. Day 3 Experiment: Rainbow Reactions Aim: Learn about neutralization reaction. We were asked to add 10cm3 of sodium hydroxide followed by 15 drops of natural indicator. Then add in 15cm3 of hydrochloric acid to the beaker. Transfer the mixture to a burette using a dropper. Measure 5cm3 of sodium carbonate solution. Transfer it into the burette. Do it quickly and then cover the mouth with a parafilm. Inverse the burette. Colours ranging from deep purple through blue, green and orange should be observed. Explanation: What is observed just now is the neutralization reaction occurring. Neutralization is a reaction of an alkali and acid. Reflection: I learnt a lot about chemistry. Just from the experiment above, I have already learnt the factors which affect the rate of reaction of chemicals or substances. Other than that, in other experiments, I have also learnt about the ph levels and how to check if a certain substance is acidic or alkali. I have also had fun and saw many exciting things just like the rainbow experiment stated above. I noticed that that is one of the many things that just make science more interesting. Day 4: On day 4, we had biology for our science eureka. Experiment: Egg Ping Pong and Rubber Bones Aim: Investigate the effect of vinegar on common household consumed products Pour vinegar into 2 beakers, and then label them ‘boiled’ and ‘unboiled’. Take 2 eggs, 1 raw and the other hard-boiled and place them into the correct beakers respectively. Leave the eggs there for 2 hours. Meanwhile, fill another beaker with vinegar and then label it ‘chicken bones’. Place a few chicken bones into the beaker. This will take a longer time for changes to happen. Leave the chicken there for about a week. Our trainers for our science eureka did it earlier so that we can observe the effect on that day. After the experiments have finished, carefully remove them from the beaker and feel them for their texture. Explanation: The egg should be soft and the chicken bones should feel like rubber and can be bent. The eggshell is made of calcium carbonate and the vinegar is a weak organic acid. If you react a carbonate with an acid, then you are left with a soluble salt, carbon dioxide and water. So the shell slowly dissolves. Thus, the only thing left to hole the egg together is the membrane which keeps the liquid in the egg, which is flexible and stretchy, so the egg is flexible and squashy. As for the chicken bones, calcium is also present in bones, hence allowing the vinegar to also react together with the chicken bones to make it flexible, like a piece of rubber. Reflection: Biology is cool. On that day, we had a lot of fun and I felt that it was my best day yet. Experiments as cool as the one before was seen throughout the day. We also did things like extracting DNA from a kiwi fruit and also making our own glue that is usable. My friends also enjoyed biology a lot. Day 5: We were asked to present a powerpoint slide on certain topics that they give. My group chose to present on Maglev trains. After the presentation, we were allowed to leave the laboratory. Reflection: Through my own presentation and also other groups’ presentation, I also learnt a lot. Even though 5 days have passed, it only felt to me as if it’s only a day’s time. I have truly learnt a lot and have many unforgettable times during the lessons. I have only one thing to say after all this: SCIENCE ROCKS!!!!