Smore Lab

Problem:  Given a certain quantity of marshmallows, graham crackers, and chocolate pieces, what is the maximum number of S’mores that can be made?  Then figure out your percent yield!

Substance Symbol
Graham Cracker (half of a cracker) Gc
Marshmallow M
Chocolate Piece (individual piece of chocolate) Cp
S’more  (2 crackers, 3 pieces of chocolate, 1 marshmallow) Gc2MCp3


1. Use the 3 different reactants and one product to write a balanced equation for the making of s’mores

2 Gc +    M + 3Cp →   Gc2MCp3   

2. What type of reaction would this be classified as?

Chemical and physical changes.

3. Record the total moles (pieces) of each reactant available at your table

Graham Cracker (Gc)-  6 Marshmallow (M)-  4       Chocolate Pieces (Cp)- 9

(amount of halfs of Gc) (each single marshmallow) (each single chocolate piece- 12 per bar)

4. What is the maximum number of s’mores that your group can make?  

Why? The maximum number of s’mores is 3 because graham cracker and chocolate pieces are the limiting reactant and only consist of a certain amount that is enough to make 3 s’mores.

Which reactant/s is/are limiting?  (the one/s that you will run out of first) : graham cracker, chocolate pieces

Which reactant/s is/are  in excess (the one/s that will be left over) : marshmallow

5. Find the mass of one of each of the individual reactants (first zero a napkin and then find the mass on top of the napkin)

Graham Cracker (Gc)- 8.17g Marshmallow (M) – 4g Chocolate Piece (Cp)- 3g

(one halfs of Gc)       (one single marshmallow)      (one single chocolate piece)

6. Record the theoretical yield/mass of a S’more (Gc2MCp3) using your reactants (you can add them together)

[(8.17*2) + (4) + (9)] = 29.34 g

7. Make your s’mores 

a. Make sure that you follow the chemical reaction equation and get all of the reactants ready.

b. roast your marshmallows over the Bunsen burner using a skewer. And then make your finished product.  

c. Before eating your s’more find the actual mass (yield) of your s’more

(put a napkin on the scale, zero the scale and THEN put on your smore).

The ACTUAL (experimental) mass of one s’mores: 29 g

8. Find the percent yield of your s’mores:.       Theoretical yield = from part 6 Actual or experimental yield= from part 7c

(29/29.34) * 100

percent yield=98.84%

Healthcare System in Cambodia

As you may know, Cambodia is a developing country and there are so many areas that we still have to concern about, one of which is how the current healthcare system work. Although our country government and many other organizations had invested in a lot of hard work into fulfilling the flaws we had in the system, the healthcare system in Cambodia hasn’t yet reached a level that we wanted to. Many medical centers were built in different places around the country and more people can now easily access the health services. The only problem is “health centers don’t treat people, people treat people.” Having many health centers is not enough unless there is someone there to serves their fellow citizen with quality health services.

For the first round of the school year 2018-2019, I attended a class called the Healthcare System in Cambodia which will continue in the second round as well. Our goal in this exploration round was to reach out to as many experts and organizations as possible in order to collect different perspectives on how Cambodia Healthcare System should be improved and those perspectives will act as the inspiration for each project we’ll be working on in the next round exploration.

On the first day of class, we did individual research on the different topic on questions we had related to healthcare system in Cambodia. I personally really interested in laboratory system in Cambodia, so that’s obviously the topic I did the research on. It had interested me more when I found that there was only one main lab that exists in Cambodia. Basically, in a lab, they worked on various projects: close observation of bacterias and viruses, the different type of infectious diseases, the Pentagon resistance to the current treatment.

The information I got from the research had brought up questions within me. After all the research I’ve done, I was still confused about laboratory role in the country and how those discoveries contribute to the healthcare system improvement.

Though for the next couple weeks, I took some break from the laboratory and started to get into people’s opinion on how the healthcare system should look like and what can we do to improve it. A lot of places we’d been to always mentioned the lack of human resources and high-quality types of equipment while some also mentioned doctor’s ethnicity, leadership, and hospital hygiene. However, I was looking forward to having someone mention something related to the laboratory system in Cambodia. But there hadn’t been anyone seems to interest in talking about that topic.

That is why I was inspired to work on a project related to lab research for the next round exploration. You might be wondering how is that connect to the healthcare system in Cambodia at the moment. I personally think that having a strong lab system will help to improve the healthcare system in a country. Labs and health centers work as one. Labs could do research on the effectiveness of any new treatment that is out so that we don’t have to wait for the result of the other country’s research; labs could do a research on the resistance of pathogens toward the current treatment we have and try to work out what could hospital do when they meet the patient with that certain disease or condition; lab could do a research on many more projects that could really bring a really valuable information for treatment in Cambodia hospitals. I strongly believe that labs do play an important role in improving healthcare system in our country that is why I will be working on a get-to-know-lab project and hoping that more Cambodia college students would find research field interesting and consider working in a lab as their career, more labs will be open in Cambodia, and more fund will go into the research field as well.

Flame Test Lab

Objective: To observe the relationship between various elements and their emission spectrum.


Flame tests provide a way to qualitatively test for the presence of specific elements by seeing colored flames.  The heat of the bunsen burner excites the electrons in the atom, and this energy is released as the electrons “fall back” to their ground states. The color we see is a combination of the visible wavelengths of light emitted by the atoms.  

If you have a spectroscope you can also make quantitative observations. A spectroscope can be used to see a pattern of narrow lights called an emission (bright-line) spectrum.  The actually wavelengths of the spectrum serve as a quantitative test to determine atoms identities.  Each element has a different “pattern” of electrons so it will show a different combination of colors.  

In this lab, you will perform flame tests on seven different elements. You will use your observations to identify an unknown solution.

Prelaboratory Questions: (In a section labeled PRELAB- answer the following questions in FULL sentences)

  1. Why do we see colors in the flame tests?

The increase in temperature makes the electrons excited and move to a higher energy level. They produce visible light as they return back to the ground state.

  1. How will we be testing the substances qualitatively?

One way could be comparing the color of flame (of each element) with the Bhor model.


Safety goggles, wood splints, tongs/tweezers, Bunsen burner, test tubes with various compounds


  1. Safety goggles must be worn at all times
  2. Many of these salts are toxic. If you come into contact with any of the compounds make sure to notify the teacher and wash the contacted area thoroughly. Wash your hands before leaving the lab!


  1. Light the Bunsen burner (turn the gas on so you can just hear it, then use the striker)
  2. Place the wood splint for each compound into the flame using tongs or tweezers- ONE AT A TIME!
  3. Take note of the color of the flame and return the wood splint to the solution.
  4. CLEAN UP YOUR STATION! Carefully put the stoppers back on the solutions! Make sure the station looks like it did when you started! Let me know if you need new splints!
  5. Wash your hands thoroughly before leaving the laboratory

Data Table: make a section of your lab labeled Data Table and make a data table similar to the one below to record your observations.

Compound The color of Flame (qualitative) Wavelengths of light (in Å) (quantitative)
Barium Chloride Yellow (light) 600 nm
Calcium Chloride Orange 630 nm
Copper (II) Chloride Green 550 nm
Lithium Chloride Red 665 nm
Potassium Chloride Pinkish-orange 647.5 nm
Strontium Chloride Red 665 nm

Discussion and Analysis: (In a section labeled Discussion and Analysis answer the following questions in complete sentences)

  1. How do your results from the flame test provide support for quantized energy levels? Explain your answer.

The heat made the atom’s element excited and move to a higher energy level. The atoms emitted photons of visible light while returning back to the ground state.

Conclusion: (answer in a complete paragraph and in complete sentences)

What are two possible sources of error for this lab? How would the errors affect your lab? What would you do differently next time to counteract these errors?

There were many barriers in this experiment: the inconsistency of how much element should be put onto the stick, how to make sure the flame is actually burning the element but not the stick. These sources of error can lead to the inaccuracy in color of the flame. If we were to redo this lab, we need to make sure that the same amount of element goes on the stick and that the flame is actually burning them. We should repeat each burning process at least three times for each element.

SAT Prep. in Math Class

Over 50% of Liger students, including me, will end this school term with SAT Exams, which I surprisingly really excited about but also nervous at the same time. The exams will be held in Liger campus on the upcoming October 6th. I had tried to spend as much time as possible into doing intense practice for the SAT mainly use Khan Academy but also SAT textbook; it had been hard to manage to do so due to the amount of homework I receive from school.

Math period had always been a time for me to study math deeply to prepare for the SAT. I can always ask my math facilitator for any math problems I struggle with. With the help from my facilitator and the self-study I’ve done, I had made a significant jump in my math SAT score.

My goal in this upcoming SAT specifically in the math section, I hope I will get no more than ten questions wrong which means I plan to get 670 or above. There are many strategies that you could use to save time during the SAT exams. Those strategies could be as simple as choosing the right way to solve each question and don’t always depend on the calculator.

For this specific questions, instead of plug in and solve, you can use the eliminate strategy:

Screenshot from Khan Academy.

x +   y = -9

x + 2y = -25

Subtract both equations and we get:

y = -16

Plug in the easiest equation and quickly solve for x.

Compare to plug in and solve, this strategy saves a lot of time. If you were to do the plugin and solve strategy:

y = -x – 9

x + 2(-x – 9) = -25

This might seems easy for this particular question, but for a lot of time in SAT, this strategy is really time-consuming and during the process of solving, you might face some stressful number like fractions as well.

In SAT exams, you got no time to waste. You can always use each second you save for the harder questions you meet. Though, you should prioritize getting the easy and straightforward questions done before spending time, solving for the harder one because each question worth the same amount of point.

Through many practices throughout the week, I feel really confident in a lot of material in math.

Though, there are still some questions that still bother me and a lot of those made up a really tiny percent of the SAT.

SAT Bootcamp

Group picture with our SAT Bootcamp mentors.

On the first day of school after the two-month holiday, we had a P-SAT test which was really frustrating. What a way to start the next school year!

As mentioned, we started this school year very differently with SAT Bootcamp for the first two weeks because many of us will be taking the real SAT exam in the upcoming October 6th which including me as well. We had three different classes in total: math, English, and an extra class for Bootcamp homework and also a class to catch up with some new information about college.

This SAT Bootcamp was just like any other SAT Bootcamp. In English section, we always started class with 10 pairs of the most confusing words in English and the rest of the class time will be focused mostly on studying each strategy to answering the different type of questions efficiently. One of my most favorite strategies was the elimination strategy. This strategy was really useful when it comes to the command of evidence question (COE). It’s really hard to explain the way I handled this type of question. Basically, I read the part A question and then go straight to the COE because instead of reading each well-written answers that are very tricky and confusing in part A, I tried to figure out the answer in part B because it usually not as tricky and later on match it with the answer from part A.

We always end English class with a lot of homework. By a lot I mean A LOT; I remembered that one time when we got 80 SAT questions to get done overnight, plus the vocab homework which was to come up with example sentences for each vocabs questions which we would then share to our classmates in the next class period.

For the math section, we didn’t really have specific strategies for each type of math questions. So basically, we tried to do as many kinds of questions that can appear in SAT exams as possible. The class would basically start with our mentor showing some convenient way to solve a question. My favorite strategy that I wanted to highlight is polynomial division, which basically works like the normal division as well. I like it for a lot of reasons and not only that it’s getting me to the right answer very quickly but also it teaches me to not afraid of fractions, or abnormal numbers because there’s always a simple way to handle things.

SAT Bootcamp had taught me a lot of useful strategies for time-limiting exams and I definitely gonna use those while taking the real SAT exam.

Dengue Fever Risks Analysis

Welcome to the Mosquito-borne Diseases exploration! This is one of the last round explorations of this school year 2017-2018 at Liger. We are a group of 12 students and a facilitator who is trying to study deeply about a very common mosquito-borne disease in Cambodia, Dengue Fever, that every Cambodian had heard of. Throughout the research, we had found that the number of Dengue Fever cases are doubled this year compared to the previous year. This information had encouraged us to pick this particular disease to focus on most. Currently in class, our teams are working on a project called ‘Risk Analysis’ where we have to survey villagers, analyze the data, and finally writing a report for the study ourselves.

The goal of this project is to estimate which village of the two are most likely to have a Dengue Fever outbreak in this upcoming raining season.

Mosquito larvae inside villager’s water storage.

We start off by creating a team to work on the questionnaire. The questionnaire will only include the relevant questions and are not expected to be a long list of the question due to the time limit; we don’t have much time to interview as well as to analyze responses of each question. There was also another team that is working on figuring out routes that each team or pairs will be taking in order to avoid interviewing the same households.

On May 18th and 19th, 2018, our team went out of campus to do surveys of our neighborhood villages: Champus Kaek, Koh Krobey, one household followed by the other. We spend approximately 20 minutes to interview each household. The six pairs complete about 60 household in that morning in Champus Kaek village and are ready to keep on the work to interview the next village tomorrow, expecting to have a sample survey of 52 at least. After the two days, we end up interview 116 household in total which was really impressive.

Interviewing one of the households.

My favorite part of the whole process is to be able to connect and feel the kindness and a warm welcoming from each person we’ve been walking through to interview them. They were really friendly in term of like respecting and letting some 15-year-old asking them questions. Getting the accurate answer from them is really important, so we have to make sure they are comfortable with telling us the information we need. I was glad to get to talk to and connect with all the villagers once again.

In the second village, Koh Krobey, we seem to run into an issue. Each route the group had divided doesn’t seem to share the same amount of household, so some group seems to struggle with completing the amount of survey they needed to get done with. I was also one of the groups who’s struggling. As I walk through the route, I try my best to ignore those dogs that were barking hard at us. After a few minutes, we make a decision to just meet up as a team and continue to interview the route with a lot of people which is another team route.

Observing one of the village’s water storage.

There were many flaws in making this report. There are a lot of different interviewers. So there’s a chance that we can interpret the question in a different way and receive a slightly inaccurate answer.

While analyzing the data, I was on a roll with the other three mates to work on analyzing the association between people’s behavior and their risk of getting dengue fever. Surprisingly, there isn’t any evidence of an association between them. This means that the risk of getting dengue fever is not influenced by their behavior.

One of the water storage type that many villagers had used.

Throughout this whole exploration, I had worked my hardest at all time! I asked a lot of questions and always pay all of my attention toward the lesson our facilitator had given us. Those questions had influenced my understanding of this topic very well. I had worked my best to connect all of the experiences from the last exploration like Surveying in Cambodia into writing the report. Lastly, I hope I had played my role well and had contributed every knowledge I have had toward making this project happen.

The Physics of Spider-man

On Monday, April 2nd, 2018, my Physics class started working on a new project called “The Physics of Superheroes” where each of us is supposed to choose a superhero that we interested, in which we will be research on the physics behind their superpowers. By the end of this project, each of us required writing a one-to-two page of well enough explanation about the complicated physics behind the superhero’s powers along with a poster that will display the important information from the writing paper as a visual product.

I chose to work on Spider-man and I was focusing on one of his superpower which was webbing. We need to properly identify the superpowers and connect them to laws of physics that exist in the real world. We also need to show that we understand most of the physics that we bring up in our paper as well as identifying which superpower is realistic and which is not. And last, I need to put enough effort into my poster and make sure that it can display important information in a creative way.

This project is really difficult for me personally because the physics behind Spider-man power is a really complex physic for me. It took me a lot of time to understand a concept. I finish my paper writing in four days and I started working on my poster the day after. This is actually how my poster turns out.

This is the poster of physics behind Spider-man.

I actually really like that this project allows us to choose the superhero that we want to research about. I had learned a lot of incredible facts from this research project and I was really happy to learn that some superpower that seems nonsense can actually happen in the real world which is really impressive because it shows that we humans are really amazing! Through doing this project, it always reminded me of a quote that says “Nothing is impossible, the word itself says I’m possible!” Please enjoy my writing that I attached here.

Camkids Surveying Exploration

On Sunday 4th of March 2018, a group of 17 students from the Liger Leadership Academy went on a trip to Kompong Speu (KPS) in the sight of interviewing people from the three villages: Chbar Chross, Trapaing Mian, and Ta Gnov. The purpose of this survey was to determine the effects that Camkids has had toward people from the three villages as well as discovering the current issues that those villagers face so that Camkids can provide services that help to solve those issues. This survey report was requested by Dominic Sharpe, country director of The Liger Leadership Academy and founder of CamKids.

The questionnaire was created by the Surveying Exploration, a group of seven students and a facilitator. I am really glad to be a part of the team because this project will help a lot with improving villagers’ lives. The question was divided into 4 main sections such as Incomes and Expenses which break down into Loan and Savings, Education, Health, and Nutrition. We spend the whole Sunday there at KPS and we determined to interview at least 80 families. Each survey took about 30 to 40 minutes. We interview individually so that we can get through as many families as possible. This includes asking questons and noting down responses as clearly as we can manage. At the end of the day, we get 103 interviews done. I really appreciate the work I’d done at KPS a lot because I had overcome the fear I had of walking toward someone and start a conversation.

Interviewing one of the villagers.

It was a really hard task due to the time limits, but our group manages to get it done really well. Currently, we’re in the process of writing the report and analyzing the data. My role in the team was to start writing the report. It was a really hard task for me personally because the report is required to be as professional as possible. By writing this report, I had improved a lot with my writing skill especially on how to make my writing professionally. The final step is to present it to Dom and the other founder of Camkids and of course, upload it onto the school’s website.

Group picture at Camkids.

If there a project related to surveying and creating a questionnaire, I think the experience I received from this exploration can be applied to that project perfectly. There were many experiences I got from this project such as creating a good questionnaire, interviewing and surveying people, and writing a professional report. Because we’re still students who learn to do this type of project and aren’t professional surveyors, there were many flaws in this survey report still.

VEX Robotics Competition in Bangkok 2018

On Friday, February 2nd, 2018, my Exploration group went to Thailand in order to attend the VEX Robotics Competition in Bangkok 2018. VEX Robotics Competition is a competition that requires the student to work as a team, using their engineering skill to design and build a robot to play against another team. It is a game of alliances which mean we will require to cooperate with the other team(s). It came with a lot of rules that we must follow in order to avoid from disqualification. We’re a team of five girls named “Beta-B“.

On Saturday, we went to NIST International School to join the VEX Robotics Competition. We went through many challenges throughout the whole competition. Before the competition, we spend a lot of our time getting familiar with the real field to fulfill the practices that we’re missing because our school doesn’t have the field.

Hanging out before the competition.

We discovered that our cortex (robot’s brain) isn’t working very well. The Bluetooth is always disconnected with the controller. So we decided to risk changing it with the extra cortex at NIST, although we didn’t know for sure if it working well. Before getting to make everything work, we’re running out of time because we must go to lunch altogether. What worse is we are one of the teams who will compete in the first round and we really don’t want to miss it in order to keep our score as best as we can.

Checking and fixing the robot to make sure everything is working well.

After lunch, we rushed back into the working room, and we weren’t allowed to get in until 12:45 pm. We were freaking out, and feeling hopeless because the competition will starts at 12:50 pm. But because of the good teamwork, we get to make everything done on time and we get to attend every round in the competition.

This is our group picture!

Finally, we end up at the 11th place. I was really surprised that a lot of teams want us to be their 3rd alliance. But we choose to team up with the top two team; the 1st place “Shadow Corruption” and the 2nd place “VEXecutioners” where they really want us to be their alliance as well. This is where my favorite part of the competition begins. We collaborate so well that we win every game smoothly and we’re getting into the final and compete with “Team A++” and their alliances.

Receiving the Tournament Championship with our alliances!

This is the video of the whole competition. You can watch us compete in the final (the 2nd round) by move the video forward to this minute, 4:54:15. As you watch the video, you will soon discover something wrong right after we finished the game.

Although we met some issues during the final game, we still get through it well and end up winning the competition and receive the Tournament Champion award!

Our robot with the champion. – pictured by Rika Chan

I had learned a lot from this experience. It isn’t just learning how to design and create a robot, but also how to collaborate with other people as well. I understand that to build a good robot, it doesn’t need to have every function but what important is that it has a function that works super well just like the one we built. If there’s a VEX Robotics Competition next time, I would really LIKE to join it again!

កំណាព្យខ្មែរ [Khmer-Poem]


[Translated into English:]


During the sad 1975, the Khmer Rouge had used violence to evacuate people out of their houses as well as their beautiful city, Phnom Penh, and people never get to return since then. They closed all of the markets and schools. We also lost our culture. Some of the pagodas and schools have turned into a prison by the Khmer Rouge and had captured a lot of our innocent people. People don’t allow to have private ownership and instead, everything belongs to Angkar. Each person has the same amount of work. Everyone is farming and must wear black clothes. There weren’t any family relationship at that time. To follow their goal of making everyone equal, they started to kill the minorities like Cham, China, and Vietnam violently. After, they started to force people to work harder by telling them to produce 3 tons of rice per hectare without giving them enough nutrition to gain the strength to continue working. If people don’t follow what Angkar said, they will be killed.

[Information based on:]