States of Matter: Lab Reports

       Throughout the week, our class completed a series of labs involving chemical and physical changes. In all labs involving the Bunsen burner, the groups had worn goggles  and the girls tied their hair back in order to protect ourselves.

       The first lab was one of the simplest. What was done was to observe a candle before and after it was lit. Before it was lit, the physical properties was the color (white), it was waxy, hard, bumpy, and spiral. These properties were determined by using sight and touch. However, there were no chemical properties right now because nothing has happened or changed. Then the candle was lit. When the candle was first lit, the physical changes were that it was melting and the candle looked smooth and shiny. The candle was also getting smaller in size. And the chemical changes were that it was burning and that there was smoke and a flame from the fact that it was lit. From this lab, I learned what combustion is. Combustion is the name given to a process such as burning a candle. I was surprised to find out that I used science every time a candle on a birthday cake is lit. Though this is a simple lab, this would definitely help me when making any science experiments, and I will be able to make hypotheses that will most likely be correct.

       The second lab also used a candle, however it involved pouring a gas on to the candle in order to observe the chemical and physical changes. First, we lit the candle and this created both physical and chemical changes as stated above. While the candle was lit, we poured some vinegar inside a beaker and then put a spoonful of baking soda. When the vinegar and the baking soda reacted with each other, creating a gas, we put the beaker right next to the flame. And because a flame lives with carbon dioxide, the gas allowed the flame to automatically turned off; and this followed by a large cloud of white smoke. We then lit the candle again and did the same procedure observing the same reactions again. This lab helped me in learning more about how flames can live and how the can die.

       The third lab involved tasting using marshmallows. First, we took a small marshmallow and split it in half, creating a physical change. The marshmallow was white, small, smooth, soft, fluffy, cylindrical shape, and the inside was sticky. After that, we ate the marshmallow. It tasted sweet, sticky, and it had a fluffy texture. After that, we took a large marshmallow and placed it on a skewer over a Bunsen burner. This was a chemical change because we had burnt the marshmallow when placing it over the fire. The marshmallow was  brown and black, even more sticky, and in a cylindrical shape. However, the marshmallow tasted chalky, bitter (no longer sweet.) The marshmallow also had a physical change; it was that the marshmallow was melted on the inside. This lab had helped me learn that even when we make s'mores, we're using science as well.

       The final lab involved burning sugar. I first concluded that we were going to make caramel. However, we were burning the sugar far beyond caramel. To start off, a sugar cube is small, a cube shape, white in color, sweet in taste, hard, and smooth in texture. We then had to crush the sugar cubes into fine sugar and this allowed us to create  a physical change. We then poured the sugar into a cup of water and tasted it. This allowed us to create another physical change because the sugar was still there even though it was not visible. The sugar also still tasted sweet. This observation reminded me of the ocean because the water has salt even though we cannot see it but can taste it. The next process was to put two whole sugar cubes into a test tube and hold it over a Bunsen burner using tongs. Water started to form in the tube because the sugar was melting. Then the sides of the test tube started to turn yellow and the sugar turned into a golden brown color. Then gradually, the sugar turned black. After turning off the Bunsen burner and setting the test tube aside to cool, my group noticed a few physical changes. The sugar was no longer small, but large and the shape of the sugar was in the shape of the test tube. The color had also turned from white to black and it tasted bitter instead of sweet. The sugar was also hard and rough instead of smooth. As you can see the sugar had completely went through a chemical change. The sugar is no longer sugar, but turned into carbon. This lab has definitely showed me the significance of chemical change in such a simple substance as sugar.
       As you can see, chemical and physical changes happen everywhere and not only when you intend to, like in a lab. Changes and properties help a person understand the substances in the world better and allow them to understand the reactions that occur with each other as well.


Sources:
http://www.shutterstock.com/pic-62515567/stock-photo-flame-of-a-single-birthday-candle-burning.html
http://ficklekitsch.blogspot.com/2011/05/hair-experiments-baking-soda-and.html
http://www.shutterstock.com/pic-1611432/stock-photo-marshmallow-on-a-stick-being-roasted-over-a-camping-fire.html
http://www.ehow.com/how_8220027_burn-sugar-cube.html

               

"Separating A Mixture" Procedure

Follow the procedure:

1. Put on goggles and make sure hair is tied back, no long sleeves, no sweaters, no hats, etc.

2. There are two toothpicks inside the cup solution. Remove both toothpicks using the plastic spoon provided.

3. Take out the big rock as well, using the plastic spoons.

4. Pressing the spoon onto the rocks and sand to prevent any substances to get into the water, pour the water into a graduated cylinder.

5. Using the filter paper provided, fold it into a cone shape and place it inside a funnel. 

*Make sure to hold the filter paper cone because it might pop out from the funnel*

6. Drain the water from the cylinder through the funnel and into a beaker. Wait for the water to filter out.

7. Plug in the hot plate. When it has heated, place the beaker onto the hot plate and wait for the water to boil.

8. While the water is heating, use the magnet given and take out the iron. 

9. When the water has boiled unplug the hot plate and the water should evaporate. When it has evaporated, use the magnifying glass to identify the salt particles.

10. Using the plastic spoon, remove the small pebbles.

11. Remove the sand also using the plastic spoon.

7 Substances Inside the Heterogeneous/ Homogeneous Mixture:

1. Water

2. Salt

3. Small Pebbles

4. Big Rock

5. Iron

6. Sand

7. Two Toothpicks

Sources:

http://faculty.sdmiramar.edu/fgarces/zCourse/All_Year/Ch100_MM/aMy_FilesLab/06LbMM_Expt/Ex04_SepTernMix/SepTernMix_OL.html

Extra Credit Response

   Respond to the following quote:
             "Education is the key to unlock the golden door of freedom"

     First of all, I believe this quote has a meaning that everyone can connect to. I believe the quote means that having an education is a very important concept, thus making it a key that most people might not have. Education is very important though many students do not notice it. It will help you in the future of being a parent, getting a job, or just living throughout life. Having an education is something many people did not have back then. 
     A key is something that people have for specific things, and so not all people have it for the same thing. An education is a key that everyone can have, either meaning as a literal key or meaning as a key to help with in life. This then opens the discussion of freedom. Freedom is also another thing many people did not have back then. This includes freedom of religion, speech, press, and everyday human right freedoms. So freedom is something big and something gold, and so if there was a golden door of freedom, then education would be one of the keys needed to unlock one of its many locks.
     Education, as I said before, is something many people back then did not have. If you were a woman, you didn't have a full education and if you made it to college, you were rich. However, if you were a slave you had no education. Being a woman or a slave back then would not give you the right or the freedom to be educated.
     Being educated would make others consider you smart or even intelligent. So education itself is also gold. It gives us knowledge; the knowledge to do things with confidence because we know we understand. And so with education come more choices and therefore more freedom to pursue one's life ambition.


Sources:
http://www.123rf.com/photo_3213693_education-is-the-key-written-on-a-chalkboard.html

The Frog Dissection

    To start off, our class started on our frog dissection on Tuesday the thirteenth and finished dissecting on Wednesday the fourteenth. Our goal was to be able to relate the systems of the frog to the systems of a human being. However, the main systems my group and I saw were the digestive system, the endocrine system, the urinary system, the nervous system, the respiratory system, and the circulatory system.
    After wearing our goggles and gloves, our frog was first put onto our tray. Then, our group opened up the frog by first "peeling" the layer of the skin and then the layer of the muscle on the ventral side of the frog. After we opened the frog, we found out right away that the frog was a female. This is because her eggs were all inside. The part that surprised me was the fact the eggs were not in one section. I thought that the eggs would either be in a sac or altogether covered by peritoneum, which is a membrane that covers the organs to keep it together. However, the eggs were not in one place nor were they in a sac; they were everywhere. After we took out the eggs, we identified the organs. The first organ we saw was the liver. The liver is the largest structure of the body cavity and is composed of three parts. Its job is to produce bile which helps digests fats. Another organ was the heart. The heart has the job of pumping the blood throughout the body to keep this organism alive. There were other organs such as fat bodies (which all frogs need), the lungs (which is what the frogs needs to breathe), the gull bladder, the stomach, both the small and large intestine, the spleen, esophagus, and many other organs as well.

    After identifying the gender and the organs, our dissection was now complete. I learned many new things from this dissection. First, the fact that frog guts do not smell very nice. Second, I learned that all systems humans have, other organisms have as well. Lastly, I learned that the systems of humans and of frogs have all the same function and that by using a frog as an example, we are able to have an idea on how some of our organs look, especially because most of human organs look similar to the ones of a frog.


http://www.scientificillustrator.com/illustration/amphibians/leopard_frog.html

http://www.dreamstime.com/stock-photos-gloves-and-goggles-image1413723
                

"As the Stomach Churns" Lab Response

        In the first day of this lab, we were seeing how the hydrochloric acid in our stomach digests our food and how acidic conditions affect protein digestion. 
       The first step was taking four test tubes and labeling all of them a different letter: A, B, C, and D. Then hard boiled egg-whites were cut into three centimeter pieces and three pieces was put in each of the four test tubes. After that process has been completed, we continued on putting either pepsin, or hydrochloric acid in different test tubes and seen what reaction occurred:
       For test tube A, with only pepsin and eggs, the immediate reaction that occurred was that the eggs started to turn a yellowish color and looked almost as if it were liquid.

       In test tube B, the water turned white and everything turned into a mushy substance (This was the tube that had the pepsin and water with the eggs).
       Test tube C had no immediate reaction, and this was the tube that had only hydrochloric acid with the eggs.
         Finally, test tube D had pepsin, the acid, and the eggs. Immediately, it felt as if the substances were bubbling lightly and started to form a white layer on the top as well as turning a clear white color.
       
         After testing all of this, we tested each of these solutions on purple-colored litmus paper. Test tube A made the paper look oily, but the paper was still purple. Test tube B made the paper look sort of a blue color. And test tubes C and D made the paper turn pink.
       Based on these observations, one day just isn't enough for out stomach to digest its food. This is why none of the test tubes had any major reactions right away. My prediction would be that maybe by the second day, the eggs will start to break down, and I think that test tube D will be the first of it. This  is because, this was the only test tube that had both the acid and pepsin added and it made a bubbly reaction, which made me think that the acid started doing something with the eggs, and possibly already starting to break it down. Also, there is hydrochloric acid in our stomachs so test tube A and B had no acid so it's least likely that any of those test tubes would start "digesting" first.

Sugar Cube Lab

This was a quick lab that was completed in class. The purpose of this lab was to see an example of digestion and how to speed it up:


First, a test tube was taken and a sugar cube was placed into it. Second, in another test tube, a sugar cube that has been crushed to little pieces was put into it. Third, both test tubes were filled with the same amount of water and were shaken for one minute. As the test tubes were shaken, the test tube with the crushed sugar cubes dissolved in the water first. 
By observing what happened, I was able to conclude that when eating, chewing your food first will help speed up digestion because the food is already  broken down and that it's less work when it reaches the stomach. However, if people were to swallow their food whole, digestion would be much slower because the stomach still has to break down the food.
 In other words, food that has already been crushed, digests faster than food that is still whole.

Chicken Wing Anatomy Lab (chicken wing dissection)

The purpose of this lab was to identify the different types of tissues and organs found in this structure.

             First, the skin had to be taken off the wing, and the wing of course is an epithelial tissue. The skin was a yellow color and a little bumpy. After getting the skin off, the muscle was shown. the muscle was a peachy-pink color. The muscle was attached to the bone, and the nerve was also located in the muscle, which looked like a red line. After observing that the muscles and nerve helps move the wing, the muscle tissue is taken out as well. That's when bones are shown and able to see the ligaments and cartilage, which are both white and shiny. The cartilage is attached to the ligament which helps attach the joints to the bone. 
             After observing all of this, I am able to see that the muscle tissue is the most tissue that helps the wing the most to contract and relax.