Thursday, November 24, 2016

Why Can Compost be the Next Recycling?


The idea behind composting is to decompose your organic waste rather than putting it in a landfill. By decomposing it, it will be beneficial both to the environment and to the plants to plants that use the enriched soil the waste decomposed in.

The way that composting works is that organic material decomposes quite quickly, especially in soil where microbes speed up the process. Certain synthetic things take much longer to decompose, like plastics and metals, so they are instead recycled. But many of the things we throw out, like banana peels and apple cores can very easily decompose. In order to compost, you need very little. All you need is the soil in the ground. However, to keep it clean and keep the trash isolated and off your lawn, I reccomend getting a clay pot and some potting soil. This will only cost you a few dollars, and you can feel great that you aren't contributing to land fills and hurting the environment. Whoever said soil was useless was quite wrong!

But actually, there is one benefit of composting I've been holding out on you. The soil you get from this is actually extremely rich in minerals, and it will allow you to begin growing a very successful garden with a few seeds, some water and a little bit of patience. You could grow food from the food you've already eaten!

Explains the cycle of composting and the ideology it. The cycle start with food, to trash, to the composting process, to soil to grow more food.


I'll be posting pictures of the compost box I'm making right now, and I'll leave some instructions on how to build one.

However, I want to relate this back to chemistry, because I want to figure out two things to make the process better. One of the main drawbacks of composting is it can stink up your entire house unless you buy hundreds of dollars of composting equipment. The other is it can take a few weeks to decompose, which means it will most likely fill up faster than the material can decompose.

I want to begin researching the science of smell, and figure out if there is some way to neutralize or at least decrease the odor given off of the system during the reaction. My hypothesis at this point is to add some reactant that bonds with the product that causes smell in the reaction. However, it isn't that simple because I have to make sure that I do not get in the way of the reaction occuring. I've found how small the difference between a reaction occuring and not occuring really is after learning about gibbs free energy and entropy. But trust me, this is a problem if this process os ever going to expand in popularity because it mercilessly stinks up your house, especially if you leave it in your house or don't do something right. I'll be posting more articles about smell the more I learn and experiment with it. 

The other thing I want to figure out is how to speed up this reaction. This increased efficiency would allow compost bags to be sold commercially or even made into boxes similar to recycling containers, especially if I can find out how to decrease the smell given off.

Who knows what the future might be like, but I hope that I can play my part in building it. The part I want to play is figuring out how to solve some of the common problems that has drawn people away from composting in the past. Who knows? Maybe if we can figure this out, there be compost boxes sitting next to every trash can and recycling bin on the corner of every street, saving the environment one banana peel and apple core at a time.


P.S
Sorry this isn't the article about kinetics I promised you guys. It is coming soon, so don't worry! But this article I want to talk about composting, what I believe should be as common a word as recycling in the near future.

Monday, November 21, 2016

Lab: The Supercooling of Water

This lab is actuall very simple, but it isn great way to learn about how entropy and enthalpy come together in thermodynamics. I have written an article as theory for this lab and as an introduction to these terms, so for the sake of time I will just build off of that.

The supercooling of water is something that occurs when you have water that is still in liquid form under the freezing point, 32°F or 0°C.

This occurs because in order for the reaction to occur, the gibbs free energy of the system must be negative.

The first time I attempted this lab, I failed because the water I used wasn't pure enough, so it froze before I wanted it to. Less pure water has a smaller change in entropy because it has a higher entropy to begin with. The change in entropy generally must be quite great for a reaction to occur, and in this case must be greater than the change in enthalpy times the temperature (~2nd 71K).
Grpah representing the freezing point and the nucleization point of water at the point with high entropy relative to the time of the reaction.


When the lab finally does occur, it happens because the gibbs free energy is not yet negative, because the change in entropy is not great enough. In order to push it over the edge, the bottle must be smashed down, increasing the entropy of the liquid enough to make the gibbs free energy negative, thus allowing the reaction to occur. In this case, the reaction is a physical change, but these thermodynamic laws still apply. The reaction is the freezing of the water in the bottle in front of your eyes, beginning from the hearth of greatest entropy where you hit it.

The change itself is very exciting when you finally get it to occur. Just remember to make sure that your water is pure, and keep in mind that the change in enthalpy doesnt have to be as high if the entropy of the system is great enough, and the more water, the higher the entropy.

I will leave a video of the reaction below, so that you know what to look for. Good luck!

Vinay Konuru







Sunday, November 20, 2016

An Introduction to Thermodynamics and the Gibbs Free Energy Law





I recently learned about the amazing science behind a part of thermodynamics, the bases behind the both the what and why of chemistry. Thermodynamics is one of two principles that defines an experiment, with the other being kinetics. Thermodynaics deals with whether a reaction will occur. Kinetics determines the rate at which a reaction occurs. These principles shouldnt be confused, because althiugh they seem interlocked by definition, they are actually independent of each other. This is why I have decided to keep this article as an intro purely to thermodynamics and principles like Gibbs free energy.

I already told you that the basic definition of thermodynamics is whether a reaction  can occur based on the entropy and enthalpy of the the reactants. Now it's time I start throwing some definitions at you so get ready. Entropy is the so called "order" or "randomness" of the system of the reactant. For example, imagine the molecules inside a cloud of smoke. The molecules in the system are going to be moving very fast and there is a large potential for different possibilities or configurations as they fly past each other. On the other hand, a solid block of ice will have little movement on a molecular scale, mostly vibrating in place based on its known properties as a solid. Entropy can be estimated based on logic, but it is quantitativelt measured in J/K based on the SI system.


A visual to understand  entropy. As the temperature increases, a trend can be noticed of large entropy increases during state changes.

The other important principle to calculate the thermodynamics of a system in a reaction is enthalpy defined as the total heat content if a system. This is measured by the internal energy plus the product pressure and volume. This isnt as easily imagined as entropy, but the easiest way to imagine it is simply state changes. The enthalpy of an ice cube is lower than that of water vapor because the gaseous state of water has greater internal energy. The unit of measurement for this is simply Joules by the SI system.

The graph above models enthalpy and expands upon what I said above. The products of a reaction typically have a lower enthalpy than the reactants. However, sometimes an initial activation energy to kick off this reaction, which is the hump in the graph.


Now for the exciting stuff. Thermodynamics is the key to calculate the Gibbs free energy of a reaction, which determines whether a reaction can happen. In laments terms, a system always wants to obtain a lower energy state, with exceptions of course. So if we had a way to calculate the internal energy in a reaction and find whether it is increasing or decreasing, we use the gibbs free energy equation.

∆G=∆H-T∆S

H is the symbol to reference enthalpy. S is the symbol for entropy. T is the symbol for temperature. G is the symbol for Gibbs free energy. If the change is enthalpy minus the change in entropy multiplied by the temperature, measired in K, is less than 0, we know the reaction can occur This is to represent that the energy is lower in the new system, shown by the negative, than before.

Demonstrates the effect of entropy and enthalpy on a reaction. The change in enthalpy(H) must be greater than the change in entropy(S) times the temperature for the change in Gibbs free energy to be negative.


Although this is a very simplified explanation of thermodynamics, it is where Ive decided to start my journey. The laws and science of thermodynamics is immense, and it takes years of study to even get a grasp on it. I have to start at some point though, so I've decided to begin with the gibbs free energy law. I will post the lab I did, the supercooling of water, to understand these certain principles further. and some interesting issues I found to have initiallt with it. It will be exciting, I promise! The theory behind kinetics will come after that but it may be a bit delayed, because I would like to conduct a lab to understand the equations better before I try to write about it.

 Stay tuned!
Vinay Konuru

Link to wikepedia articles:

Thermodynamics equations: https://en.m.wikipedia.org/wiki/Table_of_thermodynamic_equations

Gibbs Free Energy: https://en.m.wikipedia.org/wiki/Gibbs_free_energy

Entropy: https://en.m.wikipedia.org/wiki/Entropy

Enthalpy: https://en.m.wikipedia.org/wiki/Enthalpy


Saturday, November 12, 2016

Bismuth and My Key to the Amazing World of Crystals

Bismuth is quite an overlooked element in comparison to some like iron and gold. Although it may not be used in everyday life as commonly as iron, and although it may not be as beautiful as gold, it's properties are where it's magic is held.

Last Saturday, I did an interesting experiment that sparked my interest about this element. The theory behind it is the fact that bismuth has an extremely low melting point for a metal at 271.4 degrees Celsius and when it oxidizes it creates really amazing colors.

This is the one I made on Saturday, but the liquid took the shape of the soup ladle rather than the shape of the crystal it makes


I originally got the idea to make this from a YouTube video created by nighthawkinlight who creates several DIY videos. However, it wasn't until later that I realized how interesting crystals actually are. 

A crystal by definition is a solid structure that is made up of a repeating geometric pattern. This pattern is called a crystal lattice or a lattice structure. This is the most stable form of ionic compounds, but crystals can also be formed by covalently bonded molecules when all the molecules share their electrons. Common crystals that you see in every day life include ice, snow, minerals, sand and much more. In fact, 90% of solids are crystalline. 

I started off with my experiment by purchasing 100 grams of bismuth off of Amazon.com for about 6 dollars. Although this is quite an expensive rate, the product is worth it. Utilizing its low melting point, I created a molten form of the metal using a soup pot as a crucible. Then I poured the pure molten metal into a soup ladle leaving the impurities behind. As the molten metal cools, it is exposed to the oxygen in the air. By letting it cool, you can create something similar to the picture above. 

However, I wanted to create a full crystal though; not just a mold of the bottom of a soup ladle. This is when I found something called the Czochralski process, and I used it to redo this experiment a few hours ago.

The Czochralski process is one used by the industrial manufacturing of silicon wafers for semiconductors. The process is defined by taking a seed crystal and dipping it into the molten metal until crystal starts forming around it. Then the crystal is slowly taken out as the crystal continues to grow around it. This creates a long crystal.  A seed crystal is a part of the solid crystal that you are trying to create that speeds up the reaction decreasing its kinetics, because the base of the crystal doesn't have to be formed based on random molecular movement. I will leave a link for a further explanation of the idea of a seed crystal at the bottom of this post. 

However, the process of putting the seed crystal into the molten metal while both accounting for the thermal gradient(the idea that you don't want the seed crystal to melt on contact with the hot liquid metal) and the fact that you have to have some way to draw out the seed crystal slowly. In order to solve this, I froze the seed crystal for a few minutes. Then I used a piece of clay that I wedged the seed crystal into. This was my apparatus to slowly draw the crystal out with. Other things that could work include a hot glue gun stick but an iron rod would work best due to the similar crystalline structure between iron and bismuth. 


This process can be used for any metal that can form a crystal, so I decided to try it with the the bismuth. Below shows my attempt. It created a very small crystal, but it's still a start. I could have created a better crystal, but the bismuth cooled very quickly when I poured it into to the soup ladle. I still got the crystal to form around the seed crystal, but the surrounding metal cooled forming a separate crystal that stuck to the soup ladle. 

Crystal that grew off of the seed 

Crystal that stuck to the soup ladle
I may repeat this experiment in the future using a greater amount of bismuth, better equipment, and now a better understanding on how to create a larger crystal based on the mistakes that I made this time. I highly recommend you guys at home trying this same experiment because actually getting to see the melting and cooling, and see the different oxidized layers is something that is much more valuable that simply watching a video or reading an article. I will leave links of all the videos I watched and sources I read so you can get a better understanding of the process that is going on before you conduct the experiment. Good luck and I hope that you end up with some good crystals.

Nighthawkinlight video: "How to Make Bismuth Crystals"




Explanation of seed crystals: https://en.wikipedia.org/wiki/Seed_crystal

Czochralski process: https://en.wikipedia.org/wiki/Czochralski_process

Other sources: 
https://www.nde-ed.org/EducationResources/CommunityCollege/Materials/Structure/solidstate.htm

https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=bismuth%20melting%20point

https://www.youtube.com/watch?v=ObDL3hIGuIU

Note: I would personally recommend not using any utensils in this experiment that you intend on using later on, because once the bismuth cools on something, it will most likely never come off and never be clean again. Also, you may want to wear gloves whenot dealing with the molten metal so you don't burn yourself if you mess up!

Thursday, November 3, 2016

Gels are AMAZING! (and a little bit about Sodium Polyacrylate)

A few days ago, I did an experiment with water gel powder (sodium polyacrylate) I bought online. The special thing about this chemical is that it is a polymer than can absorb over 400 times its volume in water. This causes it to create a gel on contact with water, which is why it is used in diapers and as a thickening agents in detergent. However, this got me interested in gels in general.

A gel by definition is a cross linked polymer that makes up a 3D structure encompassing a liquid and holds it together through surface tension. In laments terms, a cross linked polymer is a complex molecule made up of several covalent and ionic bonds. Then, when a liquid is added to this solid, it "traps" the water around it creating a gel.

Gels are a confusing topic because of the fact that its state and properties all depend on what aspect you are looking at it. If you are talking about the skeleton structure, it is a solid, but the liquid trapped in it is still a liquid. However, gels are still extremely important both in everyday life and on the frontier of science and technology.

You don't have to look very far to find a gel in your everyday life. There are plenty of things made of gels from toys like water beads to things like re-freezable gel packs. However, they are also used NASA shuttles in technology like aerogel.

Aerogel is an invention that was created in the 1930s and was the result of keeping a gels solid structure while dehydrating it. The outcome was the least dense solid known to man to this day. It is used as an insulator of the liquid hydrogen and liquid oxygen fuel tanks on a space shuttle in order to keep it in liquid form. Without this material, we wouldn't be nearly as successful at getting into space as we are today.

I hope to do further research into gels soon, but for now I'll leave it here. Gels are grosely underestimated for their significance in our every day lives and how amazing they truly are. The next time you see a diaper, just think about the science behind it. A dirty diaper might smell horrid, but it's also amazing.

Wednesday, November 2, 2016

Biuret Reagent Protein Test

Yesterday I conducted an experiment with Biuret Reagent, am indicator of peptide bonds that transmutes into a purple color when in contact with a protein. I did this with a goal to identify if almonds genuinely did have a large amount of protein and was a viable source of it during the day.

In order to conduct the test, I used water the Biuret reagent, protein powder as a positive control, water as a negative control, and crushed almonds.

The first step was create an aqueous solution with the substance being tested in it or water that has been decanted out of it. This can be done by crushing the substance, putting it in water, and after letting it sit, and decanting the water out. This means slowly pouting the water out without letting the substance get in.

Next, you put an equal volume of Biuret reagent in the water. Mix the reagent in until a color change occurs. The concentration of purple in the new solution reflects the concentration of peptide bonds in your substance, and thus it reflects the amount of protein in it. the deeper the purple, the greater the protein content.

The liquids in these beakers are water, dosa batter (Indian bread), almonds, and protein powder
(left to right)

Now back to the test I conducted. The protein powder turned dark purple and the water turned blue as expected. Then, I tested the almonds and I found it turned clear purple. This ascertained that almonds do in fact have a high protein content in them. Along with this, it showed that the protein powder had a even greater amount of protein that almonds.

In the next few days, I plan to conduct an experiment to test for the concentration of sugar in a substance, however this time I will go further by trying to calculate the actual amount of sugar in the substance. I will be testing chocolate syrup because it will be easy to turn into an aqueous solution. I hope you learned a little from this post about the way to measure protein content in food and encourage you to try it yourself

Tuesday, November 1, 2016

Sodium Silicate

This weekend I conducted an experiment with sodium silicate that I bought online. The product was a rubber like ball that was both bouncy, but brittle after a certain point. The compound was created by reacting 40 ml of sodium silicate with 10 ml of isopropyl alcohol and mixing them created the substance almost immediately. The reaction online involved ethyl alcohol, so I want to further research the reactive properties of different alcoholsizes and test what differences between the products.

Sodium silicate is NOT actually used to create rubber balls due to the fact it can break, however, it is commonly used as an industrial cement to create cardboard. Sodium silicate is also frequently used as a drilling fluid to avoid the collapse of boar walls and is used by builders to decrease the porosity of cement through a reaction that permanently bonds it to the surface. The best use I saw online is as a coagulation  agent in waste water treatment. I will further explore sodium silicate over the next few weeks.