The IB Chemistry Standard Level Course combines academic study with the acquisition of practical and investigational skills through the experimental approach. Students become aware of how scientists work and communicate with each other. As part of the course, students must present an individual investigation called the Internal Assessment (IA). The AST Science Department would like to recognize our emerging scientists hard work by sharing their findings through the AST Science Digest.
Investigations: Sofia Barzev Fabiana GarcĂa Anna Rodas Samiah Yeh Maria Ramirez Ana Vargas Jens Rischbieth Emil Lobachev Oscar Bueso Mauricio Parodi
p.1 p.2 p.3 p.4 p.5 p.6 p.7 p.8 p.9 p.10
My name is Sofia Barzev and I am from Nicaragua. I started my studies in the American School of Tegucigalpa in January of 2014, Second semester of 10th grade. Ever since I joined this school I have been part of clubs such as Habitat for Humanity, Operation Smile, Extiende Tu Mano and cross-country. I have also been a member of the National Honor Society and Sociedad Honoraria Hispรกnica. Besides my extra-curricular activites, I am a full IB diploma candidate. Plus I am taking IB Chemistry as my extra class, therefore it is not part of my IB diploma. I just took it for fun and to acquire supplementary knowledge that would help me in my future. When I go to college I plan to study international psychology and if everything works fine I would like to continue my studies in the field of Neuroscience. To accomplish this, I am determined to go to Europe to succeed in my plans.
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For the study of chemistry, one of the most important tools that facilitates the understanding of this science is the periodic table. Its importance relay on the fact that it organizes the elements according to their similarities in their properties. This allows a quick identification of characteristics of an element by just looking at its location on the table. Moreover, I decided to investigate about the Photoelectric effect as I discovered that light intensity (type of emission/ color), and other factors (current, electron volts) had an effect on the elements in the periodic table.
Photoelectric effect interactive simulator.
By measuring the electron volts in different color spectrums in five different elements, in an online simulator, it was possible to calculate later on the Work function, the threshold frequency, and the maximum Kinetic Energy of each element, in order to identify trends that explained the photoelectric effect of the elements in the periodic table. The results of the study support the hypothesis above and the four trends found state: 1. As the atomic number of the element increases, its energy decreases. 2. As the atomic number of an element increases, and the wavelength (nm) decreases, its threshold frequency (in 10*15 HZ) increases. 3. As the atomic number of an element increases, and the wavelength (nm) decreases, its work function (J) increases as well. 4. As atomic number or the elements increases, and the Ephoton (eV) decreases, its EkMax (eV) decreases.
I am from Tegucigalpa, Honduras and I have attended AST since Nursery. I am a full IB diploma candidate and take IB Chemistry SL as my seventh course.
I first became interested in how milk is digested by our body at the molecular level with my IB Biology Internal Assessment. I decided to continue my research initiative by guiding my Chemistry IA around the following research question: What effect does temperature have on the enzymatic activity of lactase? Using an online lactase enzyme simulator, I manipulated different temperatures to test the effect temperature has on the enzymatic rate of reaction of lactase based on the amount of glucose produced.
I decided to test the following hypothesis: if temperature levels increase up to the optimum temperature level of lactase, then there will be an increase in the amount of glucose (mg/dL); however, after the optimum temperature is reached, the amount of glucose (mg/dL) produced will decrease. The investigation’s findings support the suggested hypothesis that an increase in temperature would result in an increase of glucose production, and after the optimum temperature of 40 was reached, there was lower glucose production and a decreased rate of enzymatic activity.
Through my IB courses and my involvement in extracurricular activities, I have discovered my passion for science and health. I hope I can one day return to Honduras and make a change in the administration of health care institutions and work towards improving the Honduran public health system. I hope to study Engineering Management in the near future at the University of Navarra in Spain.
The experiment was carried out in Lactase Enzyme Activity Simulator . Studying the effect variables such as pH, temperature and substrate concentration have on enzymatic activity allow for a greater understanding of the chemical and biological reactions taking place within the body, such as the ones associated with the role of enzymes in the body’s digestion of carbohydrates, nutrients, etc. Studying the whole spectrum of these variables and their effect on the activity of various enzymes on different substrates could lead to new findings and even new prompts for investigation.
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My name is Anna Valeria Rodas and I am from Tegucigalpa, Honduras. I am currently a senior in the American School of Tegucigalpa, working to attain the Honduran and American diplomas, as well as the IB Diploma, as I am a full IB diploma candidate. I have been a student at AST since I was in prekinder and have learned a lot from the staff, teachers, and students around me. They have molded me into who I am today, and the lessons I’ve learned will continue to be valuable while seeking my business and law degrees in Mercer University in the US and beyond. Reflecting back on the years I’ve spent at AST, I can only say that I am proud of the life-long friends I have made, the lessons I’ve learned, the skills I’ve acquired, and the knowledge that has opened my eyes to the world around us. While it is daunting to move on in the world, I truly believe those who I’ve met and what I’ve learned, have prepared me well for whatever challenges I might face, and I am really grateful for it.
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My internal assessment sought to investigate the effect of temperature on the rate of dissolved oxygen (DO) levels of water. Since I was a little girl, I would visit the Lago de Yojoa in my country. Nonetheless, recent local articles have claimed that environmental changes within the area have had negative effects on the lake and its aquatic life, as hundreds of fishes have been found dead as a result of lack of oxygen. Lago de Yojoa, like other bodies of water, is constantly affected by environmental changes. Due to the fact that issues with dissolved oxygen greatly impact bodies of water worldwide, it would be beneficial if researchers were to carry out more studies on how to lower or manage DO levels to prevent the death of aquatic species.
After thorough research on the topic, I decided to investigate the original hypothesis: if temperature increases, then the levels of dissolved oxygen will decrease at a fast rate. Using dissolved oxygen and temperature probes, I recorded the change in dissolved oxygen levels of regular water as it was heated.
Results showed that there is an inverse relationship between both variables and all graphs show a sharp decline after 30-40, in DO levels, thus providing support for the hypothesis. The project further confirmed the effects of temperature on dissolved oxygen levels, making it more imperative for researchers to find ways to handle factors that affect dissolved oxygen levels so as to protect the aquatic life.
With an IB diploma (hopefully) under my belt, and the priceless life lessons that my time in AST
The aim of this experiment is to contribute to the knowledge of possible improvements to the water treatment process, and therefore the lives of the greater majority in low-income countries where clean water is extremely scarce. The interest of further exploring fresh water sources roots in my prior investigation for my Extended Essay. To me, the issue of water is not only of global importance, but also arouses personal sentiments as the country I have lived in for six years is embroiled with difficulties associated with water.
I have decided to examine the effects pH has on the water treatment processes of coagulation and flocculation, for eutrophication and other types of pollution generally alter the pH of the water. Aluminum Sulfate was used as the coagulant and flocculant chemical, and the light absorbance of the mixtures of dirt water with differing pH was used to determine water purity.
Results of processed data unexpectedly reveal that light absorbance (±0.001) of dirt water is affected by pH, and the optimum pH range for Aluminum Sulfate is between 6-8. This support the notion that varying pH whether through caused human activities or natural phenomenon are detrimental to the environment. Water treatment process is a temporary solution in combating water issues, for the root of the problem is pollution of the water sources. In order to truly improved the lives of the general population, care must be taken in decrease the impact humans caused on the environment.
has blessed me with, I hope to contribute my part to the world through the scientific community. While seeking a deeper understanding in medicine, I plan to become an advocate of change with my increasing ability to communicate in four different languages. Social skills and open mindedness are essential for a career in medicine; both of which I was fortunate to have developed as I was growing up in countries across the globe. I am fortuitous enough to have grown up in such settings that pry one’s mind to be open to the constant flow of ideas, so at a very young age, I have had experiences which allow me to have insights in, and to relate with all walks of life. Apart from my determination to contribute to the creation of a world where everyone's basic human right to health is respected and cared for, I have chosen to study medicine because it is a balance between the sciences and arts, both of which are topics are near to my heart. AST has been my home for the four, constructing years of my life. I am humbled by the genuineness of the precious souls I have met in AST that with their unique characteristics, taught me, guided me, and built me into the person I am today. “I’ve heard it said that people come into our lives for a reason, bringing something we must learn”.
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My name is Maria Alicia Ramirez. I was born on August 20, 1998 in Tegucigalpa, Honduras, the city where I have been living ever since. When I was just about to hit the three year birthday, my parents decided to enroll me into the American School of Tegucigalpa. In this institution I have been since that August of 2001 and here I have lived, cried, laughed, joked, and studied with my classmates and unforgettable friends. I am currently taking two IB courses, IB Math SL and IB Chemistry. I am planning on studying engineering but before I will be an exchange student in Portugal. I am proud of my participation in three World Gymnaestrada where I represent Honduras as the five star country we are.
In this investigation, I wanted to see how the pH in water affected the growth and the way it looked. This work is important because acid rain is a huge problem in the world right now and we have to know what are the effects of this rain in our environment. My hypothesis was that if the pH of water is acid, then it will decrease the growth rate of the plant.
The results I had in this experiment were that the lower the pH, it was harder for the plants to grow. Some of the plants that were being watered with a pH of three were dead in less than a week. This helps in the investigation of acid rain because now we know that we need to take care of the environment and stop the massive pollution happening in the world right now.
For this, I bought fifteen plants and made my solutions varying in pHs from three to seven which is neutral. I watered the plants everyday and recorded the growth they had.
These are pictures on how the plants were set up. They are placed in an order where the pH is increasing. RAW DATA S ample
A (pH=2.96Âą0.01 )height cm Âą0.05 cm 1/28/16
5
1/29/16
2/1/16
2/2/16
2/3/16
2/4/16
Plant #1
14.79 cm 14.84 cm
15.47 cm
15.38 cm 15.44 cm 15.39 cm
Plant #2
21.56 cm 22.97 cm
20.96 cm
20.96 cm 20.59 cm
Plant #3
21.31 cm 20.39 cm
20.95 cm
21.34 cm 20.81 cm 21.75 cm
DEAD
2/5/16 15.57 cm
DEAD
22.21 cm
My name is Ana Isabel Vargas and I am from Tegucigalpa, Honduras. I was born on August 12, 1998 .I have been in AST all my life, since kindergarten.
Ever since I can remember, I used to read food labels for everything I consumed. When I grew up I started to notice that the numbers changed for every kind of food I ate. I compared cooked foods with vitamin C with those that were uncooked and noticed a pattern. Uncooked foods usually have more vitamin C, than those that are cooked. That was when I decided to investigate this further. Using my IB Chemistry course, I decided to investigate the following question: Does cooking time affect the vitamin C content in carrots? In order to measure the amount of Vitamin C there is in each sample taken, redox titration will be used.
When titrating, I kept mixing the solution until it reached a dark blue-black color. I then recorded how much Iodine solution was used. After doing this for the different times, I analyzed and compared how much iodine solution was used for each sample. My results showed that cooking time does have an effect in the vitamin C content in carrots. My hypothesis was proven right.
I am a full IB diploma candidate, and I have taken two sciences: Biology and Chemistry. I am planning on studying biochemistry in Lehigh University, located in Pennsylvania. I am proud of being an active National Honor Society Member, as well as a Sociedad Honoraria Hispanica member. I hope the pillars I have developed throughout my high school years and the different challenging courses I took will help me in my years in college.
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Hi! My name is Jens Rischbieth and I am a Senior at the American School of Tegucigalpa! I’ve been here at AST for quite a while now and consider myself to be a melting pot of nationalities, Germany, the United States and Honduras being some of them. I am also an International Baccalaureate Diploma Candidate that is taking all 6 required IB Classes alongside one extra IB class: Chemistry. I plan to study Computer Science in college but I am also interested in taking Chemistry courses in college so as to develop the passion I have always had for Chemistry, maybe even getting a second degree as part of this endeavor.
My purpose for conducting the investigation was that of determining more about voltaic cells, as the explanation I received in class did not suffice. What we learned in our IB Chemistry class only touched upon the basics and I wanted to investigate this further by conducting my own research rather than looking it up online. My investigation using the simulator was successful as it predicted the results that the Nernst equation gave us.
Electrochemical Cells simulator.
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The Nernst equation is the more formal mathematical way of understanding the effect of the concentrations and the data I obtained on my own would have allowed me to formulate a hypothesis similar if not identical to the one I would have obtained if I had started with the Nernst equation.
Even though people might believe my work did absolutely nothing in terms of contributing to the scientific community, it actually did contribute to the scientific community as I was able to prove the Nernst equation’s validity and applicability. I was able to meet my objectives and am happy I conducted my own research individually without looking up the answer to everything beforehand.
Hello everybody, my name is Lobachev Emil. I was born in Russia and moved to Honduras in 2013. I’ve been in AST for 2 years and enjoyed my time a lot! I am full IB Diploma candidate and will receive this document in May 2017.
The work is based on my attempt to create an electrochemical cell from materials which we use in everyday life. This may be useful for some people in limited situations or camping. Right combination of salty water, penny and aluminum foil produces small amount of electric current. This may be used to power lighter or any kind of electric instrument which does not require much energy. The hypothesis of my investigation was if there will be electric current in the end created from this cell.
As we happened to see, there was an electric current equal to approximately 1 V produced. If one would want to repeat this project it is done easily. Put salty paper on top of the penny and place aluminum foil on very top. Later combine a “tower� from this. Connect two different ends of wire to different ends on the cell and you done! The results of my work were amazing. Values were equal to 1 V of electric current this was enough to power wall watch! I met all stated objectives and contributed to area of electric research in global society.
Average Voltage for all % NaCl concentration
35 (g) +- 0.1
8.75 (g) +17.5 (g) +- 0.1 0.1
4.375 (g) +- 0.1 2.1875 (g) +- 0.1
Average
1.477
1.32
1.427
1.334
1.971
Standard Deviation
0.453
0.217
0.38
0.175
0.111
I plan studying economics and business management, since I feel myself sure in organizing any kind of project and operating work on daily bases. Some of my achievements may include graduation from music school of Tchaikovsky with specialty in piano, several medals in kumite (WKF League), professional sports membership, and of course participated in many dance shows and competitions. .
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My name is Oscar Emilio Bueso Asfura. I was born in San Pedro Sula, Honduras but have lived in Tegucigalpa for the majority of my life. I have been a member of the AST community for the past 8 years of my life. I plan to continue my education at New York University Abu Dhabi. There, I plan to major in Biology while following a PreMedicine track course. In the future, I plan to apply to medical schools in the United States to continue my studies. I hope to someday become a pediatric cardiothoracic surgeon. Some of the achievements I am most proud of are exemplified by the results of my efforts. I have worked for years with Operation Smile and have had the opportunity to organize and participate in many of their conferences all over the globe, from Peru, to Ireland, to the United States. I am proud to consider myself a global citizen, having traveled around the world in many occasions for my different school activities. I currently am a full IB diploma candidate, and am taking IB Chemistry SL as a 7th extra class. In the past 2 years, I have had the opportunity to experience the IB Program and its quality of education. Undoubtedly, I can say that the skills that I have gained are outside of this world.
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This investigation was meant to analyze the content of vitamin C (ascorbic acid) in orange juice and how shelf life affects its content. This paper is of relevance to the daily life of people. When one understands the stages when orange juice is at its best, you can get the utmost benefit from the glass of orange juice you consume. This investigation proposed that the longer the orange juice stays in the refrigerator, the lower its level of vitamin C because with time, the vitamin C is broken down into other substances.
In order to find out if this statement was true or not, the levels of vitamin C of Sula brand orange juice were measured through a period of 5 days. Each day, the vitamin C concentration was measured using the process of titration. The data result showed a negative trend, meaning that the longer the shelf life, the lower levels of vitamin C were found in the juice.
After analysis of the data, it can be concluded that the hypothesis is accepted. As theorized, the levels of vitamin C decreased as shelf life increased. Arguably, the first two days since the juice is bought would be the ideal time of consumption.
My name is Mauricio Parodi and I was born and raised in Tegucigalpa, Honduras. I have been part of the AST family ever since I was a little boy. AST has been my second home for my whole life and I have become very fond of its faculty.
For this investigation I examined the efficiency of a voltaic cell in different scenarios. I would then record the voltage production and compare it to the other results. For this lab I used the chemical reaction between zinc nitrate and copper nitrate solutions with a salt bridge of potassium nitrate. The purpose for this was to evaluate under what circumstances will the voltaic cell produce the most energy. I would then alter the reaction by increasing the temperature on each solution. With this I was able to observe at what temperature was the reaction most effective.
I developed this experiment in order to find new other alternatives for energy sources. In Honduras, the economic situation is devastating and by introducing a new and cheaper sustainable source of energy, our country could slowly improve over time. After analyzing the most suitable temperature at which most voltage is produced (applying heat to zinc nitrate), it can be evaluated that on average at 54 degrees Celsius it reaches a maximum production of 0.787 volts. When applying heat to copper nitrate, on average at 51.7 degrees Celsius it reaches a maximum production of 0.902 volts. This information is very valuable because it provides with information on the voltage production from a voltaic cell and different ways to optimize its production. Of course, the amount of energy produced by the voltaic cell is miniscule, but this is the same reason for why I chose to try to find out when was it most effectual. With this information I could then develop another investigation in which I can find a way to gradually increase even more the energy production of a voltaic cell.
As I entered high school I decided to become an International Baccalaureate diploma candidate and it has been the best decision I have ever taken. It has provided me with endless opportunities to grow as a person and to challenge myself. Now that I am graduating I will now attend Georgia Southern University. At GSU I will continue to be a proud eagle and I plan to get a composite degree of engineering and economics. The reason for this is to eventually come back to Honduras and make a difference. With the knowledge I will gain and the people I will meet, I hope to one day do something to improve my country's economy and help it exponentially improve throughout time.
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Acknowledgments The Science Department would like to acknowledge:
IB Coordinator-Daniel Dobbe High School Principal-Maria Francisca Motz Science Department Head-Marici Girón High School and Middle School Science Teachers AST Faculty
For their continuous support in providing the necessary skills and abilities that enable our students to succeed.
“Somewhere, something incredible is waiting to be known” - Carl Sagan
AST Science Digest Issue 01 May 2016