pH Lab

In this lab, we created a spectrum using cabbage juice. First, we created a controlled variable with just the cabbage juice, and we set aside 6 other test tubes for the acids and bases.

The control variable was a pH of 7, and was a light purple color.
For the acids, we had 3 different tubes
tube number 1 had 5 drops of HCL added, with a pH of around 3 and was a red color.
Tube number 2 had 4 drops of HCL added, with a pH of 3-4 around, and was a red-pink color
Tube number 3 had 3 drops of HCL added, with a pink-violet color, and had a pH of 4

For the bases, we had 3 different tubes
For Tube number 5, it had 10 drops of NaOH added, and it was a yellow color, with a pH of 12
For tube number 6, we added 12 drops of NaOH and it was a lime green color, with a pH of around 12-13
For tube number 7, we added 14 drops of NaOH, with a dark green color, with a pH of 13






4. Which drops (acid or base) caused a more dramatic change in the pH of the solution? Why?

In my opinion, the drops of bases caused a more dramatic change in color. I thought this because it already had a natural purple color, the change from purple to yellow is more dramatic. I think the change from purple to pinkish-red is less of a change. This change from the purple to the yellow color was a bigger change because it completely changed the entire color of the spectrum for example. I think this makes sense because of the already dark color of purple, adding the base of NaOH would have more of an effect of the color change. I think that this change was more dramatic just because of the already dark color of the purple cabbage juice. If the starting color was a lighter color, for example, red, I think that the acid would make a more dramatic change because it would become a dark red, but in this case, I think the base change was more dramatic. I think if the starting color was less of a factor, this experiment could have been easier to see which effects a neutral more; acid or base.

5. What did I learn?
I learned a lot from this lab. I learned about the whole acid vs. base idea, and how each of these acids or bases effect each of the neutral pH colors. I learned about how the pH is affected, specifically by acids and bases, or HCL and NaOH. I also learned about adding acids and bases to neutral solutions, and that it often takes a lot of a certain acid or base to create a bigger change in color. For example, we had to add a lot of the NaOH to create a distinct change between the others. At first, we added around 3, 4, or 5 drops of the NaOH but these colors were not really any different. We later had to add a lot more of the drops to get a real change between the different test tubes.

This is my interpretation of the graph of this lab. I used the pH as the x variable and put the (0,7) variable in as well.

Also, you may notice the Our own experiment sign. This specific beaker was when we tried to add bases and acids together into one test tube to see the color. I believe that we added too much base because it ended up being a yellow color, similar to the other bases. We also tried to create different colors like blue and we created this by adding the base and more cabbage juice to get a blue color. I think this makes sense because the already dark color of the cabbage juice often overwhelms the base or acid colors. 

Here are some more pictures. Here is a picture of the pH scale for reference, along with some pictures of our clean lab table. Here are more pictures 

In this lab, we measured the pressure in the popcorn kernels. The popcorn kernels have water inside them, and when the water boils and has a lot of pressure, then it pops and becomes popcorn. First, we weighed all the measurements.

2.34 grams of water for 5 mL of water
30 kernels in total which was 4 grams in total
water displacement with kernels- 4.8
final weight- 118.5 including all the popped kernels
before popping 120.5
20 kernels popped, 10 did not.

4.8 divided by 30 is .16 and multiplied that by 20 is 3.2 mL.

then I took the 2 grams of the mass of H20 loss and found that that was.11 moles H2O

then I took the PV=nRT formula so
(.11 mole h20)(498 K)(.0821)
over 3.2 mL for the volume

with this equation, I got 1.45 and that divided by 20 of the number of kernels popped is .07 which I am sure is incorrect.

6. I think all the kernels did not pop because it got too hot. Most of the kernels, as you can see in the picture above that, did not pop looked like they were burnt, rather than popped. I think we may have used too much oil, or the oil was not evenly distributed so some of the kernels popped and others did not.
7. Obviously, something went wrong with our calculations because we got .07 atm per each kernel. I think it's because a lot of the popcorn pieces we counted as "popped" were not really popped, and were more of just bigger pieces than the kernels. I think also the moving of the bunsen burner could have affected the end result because there was an uneven distribution of the heat produced by each kernel. There also could have been a lot of miscalculations on the weight of the products, or the kernels could have been just bad.

I think if I were to do this assignment again, I would use different kernels and be a lot more precise with all the measurements. I would measure with a digital scale, rather than a 3 beam balance scale. I would use a more precise amount of oil and be more even with all the fire with kernels. I would also try out different numbers with the number of kernels. I would also try to be more precise with the counting of the kernels and the ones that did not pop.

In this experiment, we tested the pressure caused by mentos and diet coke. First, we took an empty bottle of coke and cut in half, to create a base or launch pad. Then we took a paper clip and put 5 Mentos onto the paper clip, and put that onto a cork. Then we went outside and put the cork with the mentos on top of the coke bottle. then we flipped over the coke and it created a rocket.

Why?
Due to gas laws, and the pressure we created, it created a huge explosion, making it look like a rocket. This is a process called nucleation, where a large amount of carbon dioxide in the diet coke is attracted to the Mentos, causing an immense amount of pressure, thus causing it to explode. Because we put a cork on top of the bottle, the pressure increased greatly. Because the also flipped it upside down and had a base, it was able to fly higher. The Mentos sank because they are fairly dense, and then quickly created bubbles. Low surface tension also helped the bubbles to grow faster. Diet coke works better than normal Coke because it is lower than in sugary water, creating a better rocket.

Gas Laws:
Due to Henry's Law, P=Kc. the p=partial pressure of the gas, K is the constant, and C is the molar concentration of the solute. This is why sodas fizz when you open them. The bubbles form in liquids due to the dissolved gas, and it is easier to form in soda than water. A nucleation site is always needed to form bubbles.

What went wrong?
I think the main reason this went wrong was the weight of the 2-liter bottle of coke. This was a lot of weight for only 5 mentos. We should have either have smaller bottles of coke, or more mentos in the bottle. We could have had two paper clips of mentos and a smaller bottle of coke and it would have flown much higher. Both of these would have increased the pressure, and decreased the weight, thus making it fly higher. Other factors such as temperature, angle, and inproper cutting could have also effected this procedure.

Limiting Reactant Lab

Analysis questions
1. What are the limited and excess reactants for each flask? How did you determine this?

The limited reagent was the baking soda for the flask with 1 and 2.5 grams of baking soda. For the flask with 4 grams of baking soda, and our own personal experiment, the vinegar was the limited reagent. Below is my work for finding what each limited reagent is. I found that for the flask with 1 and 2.5 grams of baking soda, this was less than the controlled variable, meaning that the baking soda was limited.

2. How is the amount of product in a reaction affected by an insufficient quantity of any of the reactants?

If a reaction has a limited quantity, it will not be able to completely finish it's reaction. When there is a limiting reaction, the end result will be heavily affected due to the limiting reactant. They results will not be accurate or precise due to the lack of true experimental values.


3. Which balloon was the largest? Explain.

The largest balloon was our personal experiment. We filled a balloon with the rest of the baking soda, which was around 10.75 grams of baking soda, with a radius of 6.37. This was the biggest, but the biggest balloon from the actual experiment was the balloon with 4 grams of baking soda, with a radius of 5.57.


4. Which balloon was the smallest? Explain.

The smallest balloon was the green balloon, the one with the least amount of baking soda. This one had 1 gram of baking soda, and reacted with the least amount of time. This had the least amount of baking soda, which meant is had the least amount of carbon dioxide in the balloon. It's radius was 2.47.


 5. Rust is produced when iron reacts with oxygen. How many grams of Fe2O3 are produced when 12.0 g of iron rusts?

4Fe(s) + 3O2(g) → 2Fe2O3(s)

It forms a total of 17.2 grams. My work is pictured above.



6. What real-life applications can this concept of limiting and excess reagents be applied to?

Limiting and excess reactants can be applied to real life because when certain items are limited, it affects the goal you are trying to attempt. For example, if your energy is limited, then the rest of your day will be affected due to the limited reactant.

electrolytes in my fridge

Common Electrolytes in my Fridge;

• Orange Juice
• Spinach
• Coconut Water
• Kale
• Fruits
• Pickles
• Olives
• Milk
• Cheese
• Yogurt
• Eggs

thinking about electrolytes and conductivity

In this lab, first we got all of our materials, like the pennies, salt, water, vinegar, matte paper, sandpaper, and LED lights. Then, we started rubbing the copper of the pennies for 4/5 of the pennies on the sandpaper, and then we soaked the matte paper in a solution with vinegar, salt and water. After this, then we put the matte paper, and the pennies together with the LED light. We tried using other LED lights, with different colors, and tried re-doing the solution, but none of them worked. 

The reason all this happens because it's like a battery. Because of the positive and negative sides, it creates a battery-like product. Unfortunately, ours didn't work. When metals are connected to  electrodes, and are connected to a wire, the electrons move from one penny to the other, creating an electric current. The reason our didn't work could have possibly been because we used a 1982 penny, which would have not been a post-1982 penny. Also, our solution could've been wrong because we could've used too much or little water, salt or vinegar. The mattepaper soaked in the electrolyte-like product due to the acids, created an electrolyte between the two pennies. Alessandro Volta, who created the first battery, which is why this is called a voltaic pile. 

Here are out pictures of the lab. First, here's a picture of the pennies on the sandpaper, then there's a picture of the final penny battery. As you can see in the bottom two pictures, the LED light did not turn on.

Here is a snippet of my excel worksheet of my observations of the Reactivity of Metals lab. In this lab, we put the metals magnesium, sodium, lithium, aluminum, and calcium into a mix of vinegar, water and a universal indicator. We would time how long it would change from the reddish color, to a blue or purple color once the metals would be dropped in. We found out that certain elements like sodium will have an immediate reaction when dropped into the vinegar and indicator mix. Other elements like Calcium and Lithium took longer than sodium, however still reacted extremely quickly. Lithium and Calcium took around 12-14 seconds each. Other elements like Magnesium and Aluminum kind of just dropped into the mixture and didn't react at first. It sort of bubbled for seconds, and then didn't do much. After we waited for 3 days, Aluminum still stayed as a reddish color, as seen in the photo below. It turned more of an orange color, a lot lighter than the original substance. However, Magnesium completely changed colors. As you can see, it turned into this blue, turquoise color, changed from the reddish solution that you can see in the pictures below.

I learned this happens depending on its number of valence electrons and orbitals. Sodium turns immediately because it only has to get rid of one valence electron, and it has a 3S orbital, rather than a 2S orbital like Lithium has. I assume the lower you go on the alkali metals, the faster the reaction will be. Elements like Lithium will be slower than Sodium, yet still faster than any electron with more than one valence electron. Calcium and Magnesium take longer to react because they have two valence electrons, and it's much harder to get rid of two electrons than one. For elements with two valence electrons, it must get rid of two electrons in the outermost shell, which is much harder than to get rid of one valence electron in the outermost shell. Aluminum takes the longest because it has the most valence electrons out of all the 5 elements. The more valence electrons the element has, the longer it takes to react. Aluminum has 3 valence electrons, more than any other element we tested. Also, magnesium and aluminum are on the same 3rd period, meaning that aluminum will take a similar amount of time to react as magnesium.

Here are some of the pictures we took. I tried to put them in order of before and after, but the pictures were too big and would not let me place them. 

 

My surface's touch screen doesn't work so I had to draw everything. My 8 trends include
1. Finger numbers
2. Facial Expression
3. Arm Position
4. Size vertical
5. Size horizontal
6. Pattern
7. Number of curls
8. Arms number

The number of fingers, arms and curls increase my group number. The facial expression continually gets happier as it moves down until the noble gases. The arm position, similar to number of fingers continually moves down. The size gets smaller when you go down in periods, and the size gets bigger when you go across by group, and the pattern stays the same within the group.

here is my drawing of an unknown alien and my table. I arranged this in terms of number of fingers. This is similar to the Medeleev and Moseley table because the rest of the class will have different orders. Other groups may arrange this by things like hair, or body, which was similar to how they arranged the periodic table before there was a universal way to find atomic number, or atomic mass, and before there was a universal periodic table, the first introduced by Medeleev. This is very similar to Mendeleev because there is an unknown box that was left, just like in this table. Because there is a blank in the table, it allowed Mendeleev to know there are unknown elements, while there were boxes for elements that were known like Gold, or Silver. This project explains how hard it was to do experiments before there was a universal table or way to find atomic number.

Mendealien Analysis
1. In what two ways are all the species different?
All the species are different in ways like body type, hair, number of fingers, and design on their chest.

2. What do the species in a row have in common?
On the secret agent guys PDF, the rows all have very similar body types.  similar to the periodic table, certain elements close to each other like metals, nonmetals and noble gases will have very similar body types.

3. What do the species in a column have in common?
On the secret agent guys PDF, the columns all have diverse types of bodies. Every row down gets bigger, similar to the periodic table. For example, for the noble gases, they will each get bigger in terms of protons, similar to this alien chart.

4. How do the numbers of fingers relate to the periodic table?
On the secret agent guys PDF, the number of fingers goes up one per each box. The number of fingers are like the atomic number. It has specific orbitals, like the S or P. Once it reaches a certain amount, it needs another orbital.

5. How do the arms relate to the periodic table?
On the secret agent guys PDF, one arm is like the s orbital, once it reaches 2 fingers, it needs another arm. Once the next arm reaches 8 it needs another arm, just like the P orbital. Then, once the next arm reaches 8, it needs another arm.

6. How do the number of hairs relate to the periodic table?
On the secret agent guys PDF, the number of hairs is somewhat random. It starts with one, then two, then one, then two and then goes up from there. However, certain mendaliens have only one hair, rather than going up one in a sequence.

7. How do the markings on the chest identify the agents compared to the periodic table?
On the secret agent guys PDF, similar to the hair is somewhat random. It will go in a certain order, like the small chested aliens will have dots or arrows, however some small chested aliens also have plaid designs. In my opinion, there is no set design, purely random.

Think Critically
1. a; 651.3
b; 486.3
c; 434.2
d; 410.3 all in nano-meters

2. Yes, most of them are the same, but around .1 off. My rounding may have been different from the universal type of rounding.

3.  a; 3.05(10^-19)
b; 4.09(10^-19)
c; 4.58(10^-19)
d' 4.84(10^-19)

4. wavelength 2.28(10^-6)
Energy= 1.99(10^-25)

In this activity, I used the Rydberg constant to find the wavelengths or certain electrons. I put the work to my answers on the bottom. The Rydberg equation is like Planck's constant to find the wavelength of spectral lines. This describes the relation between wavelengths in spectral lines and alkali metals. The Balmer series represents colors, for exaple, 3-2 is red, 4-2 is aqua, 5-2 is blue, and 6-2 is violet, everything else is an ultraviolet color.

 1. Copper
2. Iron
3. Sodium
4. Potassium
5. Strontium
6. Calcium

certain elements like lithium or sodium are harder to control their electrons because there are so many electrons on the outside.

elements like fluorine or bromine are easier to maintain the electrons because there are less on the outside.

The electrons on the outside want to follow the Octet Rule and gain 8 electrons like Neon or Helium. That’s why certain elements will give up elements, and others will take elements. The different colors of the flames are a result of energy. Their atomic emission spectra affect the frequencies of the light, the flame color depends on the chemical additives. Certain flames are a combination of colors because the element has not been fulled burned off yet. As the electrons return to lower levels, they emit colors characterized by a color spectrum Analysis Questions 1. Suggest a reason why each compound produced a flame of a different color, even though they each contain chlorine. Even though they all have chlorine, the chemical makeup of each element is different. For example, certain elements like iron will have more electrons than others.  After the flame, the electrons would drop a level. The color depends on the difference in the two energy levels 2. Explain how an element's flame test might be related to its atomic emission spectrum.  The color of the element is the combination of all the colors of light produced by the element.  The colros are a result of the visible spectrum.  The color results from the return to lower levels after the flame, causing the amount of electrons which causes the different color of flame.  3. Infer the identity of the unknown crystals. Explain your reasoning.  The table on the left shows what we thought each element was. We decided each of these by the color of the flame, and we decided some were the same element because of the color of the flame was the same, and the material that was burned looked, smelled, and weighed the exact same.