Sembawang High School runs a research program for students to find answers to just about any question they can imagine. We are reviewing four research projects ranging from “How Long Should I Cook Vegetables?” on “Is pouring hot water different from cold water?” No kidding!
Lee Qing Ping
Which toothpaste has the best whitening effect? Should I use baking soda or baking powder? Does the temperature of the water affect how it sounds when it is poured? These are curious scientific questions into which students immerse themselves in the Sembawang High School research program.
Available to all 1-3 high school students, the open-ended inquiry model – where there aren’t too many stupid questions – allows students to satisfy their curiosity. Through a scholarly approach, faculty guidance, and great perseverance, students test and find answers to their chosen research questions.
If you want to find out the answers to the above questions, read on.
1. From which baking powder is the softest cake?
Students carefully prepare the ingredients for their experiments.
“Our team loves to bake, and we noticed that different recipes require different baking powder, but we weren’t sure why,” says Kaushikashri Tamilka, 4th High School this year. Together with their teammates, Anyakaba Regina, Gonzaga Pamela Malar and Sayed Lirun Raizal Al-Edrus, they decided to gain a deeper understanding of leavening agents such as baking powder.
Through some research, they learned that the type of baking powder used in baking can affect the density, elasticity and hardness of cakes. Their experiments examined these three variables and four different types of baking powder: single-acting baking powder, double-acting baking powder, a mixture of both, and baking soda.
Their results: the cakes they baked from the double-action leaveners were much more elastic, softer and less dense than other cakes.
“I wanted to present science in a non-traditional way, so I decided to find out how food and science work together,” says Regina. “For me it was a whole new world! Research is painstaking. My team and I had to repeat the baking process in exactly the same way more than 20 times, but changing the dissolving agent used. ”
Kavshikashri (left) and Regina (right) proudly wave their rugged laboratory equipment.
Kaushikashri also says he had to stay after classes to conduct his experiments. Despite these less glamorous parts of the process, both students found time to spend well. Values such as patience and perseverance have been put into practice, Kaushikashri says, and Regina has found solace in the society that has pushed them.
2. What brand of toothpaste makes our teeth whiter?
Students conduct an experiment to quote eggs.
We have seen advertising: all other brands of toothpastes claim that they are recommended by four out of five dentists. But is that true? 3rd High School students Sherin Gondaros, Xenson Eng, Sven Lowe and Pryanka Babu have taken over the investigation.
Specifically, their project considered which brand of toothpaste is more effective for teeth whitening. Because eggshells and human teeth have a similar chemical composition, eggshells were immersed in various solutions of cola, fruit juice, coffee, and distilled water for six hours. Then, using an electric toothbrush, a small area of the eggshell was cleaned with one of the four brands of toothpaste tested by the team.
“The project allowed me to see how science can be used to determine the effectiveness of a daily product that we take for granted,” says Sherin, of how the investigation allowed her to know more about what to look for in an effective toothpaste.
Xenson Eng (left) and Sherin Gandarosa (right)
Xenson echoes her feeling: “Once I learned that more expensive toothpastes might not give me whiter teeth, I became more prudent in my purchases. Working together has made learning a lot more fun than if I had dared to do it alone. ”
3. Is the sound of pouring cold water different from pouring hot water?
“We knew that bottles with different water levels make sounds of different pitches. So, I was interested to know if the temperature of the water will affect the height of the sound that occurs when water is poured into a container, “- explains the student of the 4th high school Fakrudin Husseini Jaffara Taj. Last year, Jaffara and her teammates Satish Kavshik and Chan Xi Kiyat sought to satisfy their curiosity.
As it turned out, the work that was needed for their experiment was more than what they were taught in high school. But under the guidance of teachers, they mastered new skills such as analyzing scattering diagrams and sound frequencies for their project.
Jaffara and her reliable thermometer.
Their experiments were not as simple as they had hoped. They observed a general trend that the hotter the water, the higher the frequency of the sound, but were unable to gather data to prove it. However, they learned to identify the sources of errors and pondered what they would have done better if they had tried it again – it’s all part of the scientific process!
4. How long should you cook vegetables to keep it nutritious?
Vegetables are an excellent source of vitamin C, but a large amount of it is lost during boiling. What is the duration of cooking greens? Philip Lim, Niranjan Murali, Celine Lim, Celesta Lim and Mohamed Daniel want to know. They mixed and filtered the green peppers before adding distilled water and heating the solution for various times. The team then determined the amount of vitamin C in green pepper after each heating by titration.
Philip and the biuret, an instrument with which he is now well acquainted.
“I enjoyed conducting a real-life investigation with friends to find out empirically how the vitamin C content of green peppers decreases when boiled,” says Philip, 4th High School this year. He also shares how they learned that because vitamin C is soluble in water, it is quickly lost when boiled in water.
“We wanted to explore this because it has to do with everyday life. It is important for us to know how to cook nutritious meals ”.