Tie Dye Lab: Post 1

Dyeing fabric is a practice that literally goes back almost to the beginning of time. The first recorded use of dye and dyestuffs was used in China in 2600 B.C., that's 4614 years ago! Alexander the Great even found 190 year old royal purple robes (worth approximately $6 million!) in the Persian empire Susa, when he conquered it in 334 B.C. That brings up an interesting point, purple dyes, more specifically Royal Purple dyes, have long been associated with royalty (hence the name Royal Purple) For generations purple clothes were reserved for only royals, and that may be because the key ingredient for the dye had to be extracted from small mollusks, and that was not an easy job. About 1700 years later Pope Paul II introduced the Cardinal Purples, though these colors were actually scarlet, these too became known as luxury dyes. Now, obviously since the king, queen, and pope were wearing purple and red cloth then everyone else had to wear purple and red cloth too right? The answer is yes, the earliest dyes were highly valuable and constantly sought after, that's probably another reason why dye was reserved for royalty. However, even though dye was rare and valuable, it didn't actually work that great. The cloth the dyes were put on typically were not treated with mordents, so the colors leaked out with every wash and faded in sunlight.

According to Wikipedia, in a fiber reactive dye "a 1)chromophore contains a 2)substituent that is activated and allowed to directly react to the surface of the 3)substrate. Reactive dyes have good fastness properties owing to the bonding that occurs during dyeing." This means that an 1)atom that is responsible for the color of a compound contains

an 2)atom(s) takes the place of another atom(s) occupying a certain position in a molecule and allows it to directly react with the 3)surface of a substance that underlies something else or has a process occur on it. If I simplify this explanation more I would say when you put the dye (color) on the cloth the molecules in the dye replace a molecule in the cloth so that it (the color) may attach itself to the surface of the cloth permanently.

**The words in the Wikipedia definition with a number next to them have a definition with their corresponding number.

The chemical structure of dye molecules and how dye molecules bond with things actually have an interesting story behind them. The following is a photo of and indigo molecule's journey into becoming blue.

The first compund labeled Indican is the compound that comes out of the indigo plant. Indican has an attached glucose unit and is colorless until it is fermented under alkaline conditions (otherwise known as bases) and the glucose unit breaks off. After fermenting in the base Indixal is produced. Indoxal then reacts with oxygen in the air to produce the blue color we know as Indigo. The Indoxal compound doubles and flips to form the actual Indigo compound. 

The following is a photo of the Tyrain Purple compund. It's 'journey' into becoming a Tyrain Purple compoundis much like that of the Indigo, however, it does not need to be fermented. Tyrain Purple is actually a derivitative of Indigo. The compound harvested from the mollusk's secretions has attached Bromine atoms and an attached glucose unit (like the Indigo). When the compound is oxidized in air the color is released. 

 

Now lets talk about how we see colors. When you look around your house, you can tell that everything is a different color, but do you know why? It has to do with the wavelengths emitted from the different colors. The color is a physical property of chemicals that usually comes from the "excitation of electrons" due to the absorption of energy performed by the chemical. What you see is not the color absorbed but the complementary color from the removal of the absorbed wavelengths. I borrowed the picture below from www.societyofrobots.com to show you the kind of wavelengths and colors people can see.

                                 

When the wavelength is within the visible light spectrum (Between 390nm and 700nm) it is called visible light, people cannot see ultraviolet or infrared rays. Something I learned from the Societyofrobots.com is that color does not actually exist, the color we see is actually somewhat of a byproduct of the molecules emitting light. Each molecule is formed differently so it absorbs a different amount of light, thus giving off the colors we see. Each color emits light at different wavelengths and at different frequencies.

 

Now lets talk fibers... yay! In this particular lab we used fiber reactive dyes to tie dye our shirts. Earlier I talked briefly about what a fiber reactive dye actually is, but not what it does, now you'll find out. Certain dyes react better with certain fibers, in our case, cotton. If you plan on using fiber reactive dyes you MUST use a cotton shirt, cotton/polyester blends don't work because polyester is a synthetic fiber and dyes wash out of polyester, as a result you will have a faded shirt, and tie dye is no fun if the colors aren't vibrant. Silk and rayon are also good choices of materials you can dye. If you're not concerned about how rayon wears, rayon is actually the best kind of material to dye because it is made of processed cellulose and the cellulose is more readily available to react with the dyes.

 

Before you actually start putting the colors on your shirt, you have to treat the shirt with a mordant first. Decades of tie-dyers have learned that a mordant is key to a vibrant and long lasting tie dye shirt. Mordants are usually inorganic oxides that combines with a dye to fix it to a material. In other words, mordants are chemicals you need to soak your shirt in so that the dyes don't wash out every time you wash it. In this lab we used Sodium Carbonate. 

Okay, we are finally to the actual dyeing part! Yay! I have prepared step by step instructions and list of materials for you to follow. 

-Materials:

   *Sodium Carbonate

   *Plastic bin

   *5+ sheets of newspaper 

   *A countertop (most likely one you dont mind getting messy)

   * 3 pipettes 

   *Colors of dye

   *Rubber bands

   *A 100% cotton tee shirt (or whatever else you want to dye)

   *A plastic garbage bag

  

Step 1:

   -Fill the bin with enough Sodium Carbonate to soak your tee shirt

      *leave the shirt in there for many hours

Step 2:

   -Take your shirt out and wring out as much liquid as you can

      *Sodium Carbonate is a skin irritant so WEAR GLOVES!

Step 3:

   -Lay your shirt out on the counter and twist or scrunch the pattern you want your shirt to have

      *You dont have to add the newspaper yet

Step 4:

   -Put the rubber bands on your shirt in a cris-cross pattern so that it won't un-fold (use 5 or more bands) Your shirt should be in a small pie-like shape

Step 5:

   -Pour 50-100 mL of each color into their own beakers (if you have 3 colors, you'll need 3 beakers) and put a pipette in each beaker

Step 6:

   -Lay the newspaper on the counter

Step 7:

   -Use the pipette to drop the dyes onto the cloth

      * Be somewhat generous here, you dont want too much white space, but dont use to much or your colors will bleed together. 

***USE COLORS THAT LOOK GOOD MIXED TOGETHER OR LEAVE WHITE SPACE IN BETWEEN***

Step 8:

   -When you think that you are done carfully take the shirt pie off the newspaper and place it inside the garbage bag

      *Tie a knot in the bag

Step 9:

   -Wait for 6+ hours for the dyes to soak in and complete chemical reactions

Step 10: 

   -After 6+ hours take your shirt and the emptied bin outside

      *Fill the bin with water and soak your shirt in it

      *Keep filling the bin and rinsing your shirt until the water isnt overly colorful anymore  

Step 11:

   -Wash shirt in washing machine either by itself or with items you dont mind the dye bleeding on

Step 12: 

   -Wear your shirt!! 

     

Candy Lab: Post 3

      After conducting our lab I was able to make some conclusions about what I stated earlier in Candy Lab: Post 1. However, I also had some misunderstandings about crystallization. As far as my conclusions go, I am now able to better understand the processes of solubility and concentration having been able to observe it first hand. For solubility, after we poured the sugar into the mixture and stirred, you could see that the substance was hazy. As the substance got hotter, we saw the liquid become clearer. From this I was able to conclude that sugar does indeed dissolve better the longer it is exposed to a hotter temperature.  For concentration, the sugar was dissolved at 110 degrees so by the time the concoction got around 260 degrees we added 1 drop of each color, red and blue, to our boiling sugar. Since it was at a rolling boil the sugar almost instantly turned a pale purple. Then we added our flavoring after the boiling ceased and since it was maple it turned (the mixture) a somewhat nasty shade of brown. So we added a few more drops of red and blue to give the liquid candy a nice shade of dark purple. From this expiriment I concluded that if there are multiple colors in a mixture, they can cancel each other out and in order to get the color you want, there needs to be a much higher concentration of that color.  Now my misunderstanding was the candy crystallization. I didn't see any of that while the candy was boiling or while we were pouring it onto the wax paper. I went back and reviewed our recipe and it only mentioned crystallization once: you need to scrape excess sugar crystals off the sides of the can while the sugar was boiling. If you look at the photos I took of the cooking process (on the observations blog post) you will see there wasn't any visible crystalization on the sides of the can. I'm not saying crystallization wasn't part of this lab, I just wanted to mention that I didn't witness it first hand in this particular lab. 

      If I were to apply what I have learned and stated to another substance, I would choose to apply it to salt water, since salt has very similar characteristics to the finished hard candy product. I say this because I can apply all of my earlier statements about the hard candy and candy making process to salt and have the very same explanation for both. For example, concentration. If you just put a few grains of salt into, let's say a cup of water, you don't really taste it; but if you put a whole table spoon of salt in the same amount of water, the salty flavor becomes very over powering. This is just like my comparison of one drop of food dye vs. several drops of food dye; one drop only adds a tiny bit of color, but multiple drops make the color very vivid and noticeable. As for solubility, if you put a teaspoon of salt in a cup of room temperature water and only stir it, it takes quite a while to completely dissolve. If you put a teaspoon of salt in a cup of 110 degree (like our lab observations) water and stir, it only takes a few seconds to dissolve. On a larger scale, like with the candy making experiment, the sugar takes a while to dissolve in room temperature water but if you put it in hot water, the sugar takes less time to dissolve. Finally, I still believe that there is still a lack crystallization in both salt and sugar. When I think of crystals I think of snowflakes with feathery whispy ice particles extending outward. I never really witnessed any of that in any stage of the sugar or in salt. However, I do believe each individual grain of sugar and salt is a crystal, but at no point did sugar form another kind of crystal that I was able to witness. The same would go for salt, I think if you could put a bunch of salt in water, then let the water evaporate the salt crystals would look the same as they did before exposed to water. 

     If I was going to compare my results to another person's results I would go through a series of equations that look like this:

 2 cups sugar X 206g sugar/1 cup sugar 

                         = 412g sugar 

                   (How much sugar was used) 

3/4 cup water X 236 mL/1 cup X 1g/1 mL 

                         = 177g water

                    (How much water was used)

412g sugar/ 412g sugar + 177 H2O 

            = .699 ==>

                               69.9g sugar/ 100g  (Another way of finding the amount of sugar used)

412g sugar/ 177g H2O

    = 2.33g ==> 

                          233 g sugar/100g water  

In our lab, in 100g of water there is 233g sugar. In the example solubility curve, in 100g of water there was about 170g of sugar. As the temperature rose, the example sugar's dissolving rate increased from about 30g/ 20 degrees to about 50g/ 10 degrees. My data would suggest that the sugar in our expirament rose about 2.33g/ 10 degrees. 

Lab Observations

This is what we discovered while conducting our lab.
        _The sugar dissolved at 110 degrees
        _The mixture boiled at 210 degrees
        -The stuck temperature was at 223 degrees
        -Steam was rising at 210 degrees
        -The maximum temperature the substance reached was 305 degrees

Boiling sugar 

Sugar with food coloring  

Our concoction hardening 

The finished product!! 

Solution Molecule

This is my drawing of a glucose molecule being hydrated by H20 molecules.

Candy Lab: Post 1

     The purpose of the is lab is to learn about the solubility and crystallization of sugar in water while also learning the process of candy making and applying chemistry to this process. The terms solution, solute, solvent, solubility, crystallization, concentration, and molarity will be important to know for this lab

     Before making candy you first have to know a thing or two about candy itself. Hard candy is made by heating sugar to at least 160 degrees Celsius, adding flavoring, and letting cool to a hard, solid candy form. Then you must learn a few important terms you will be working with in this lab. Solubility is the ability for a solute to dissolve in a solvent. An example of this could be salt (NaCl) dissolving in water (H20). Solubility (you may know it better as dissolving,) is important in candy making so that the flavor or coloring is even throughout all the candy. Crystallization happens when solid crystals form from a liquid and are deposited by a gas. Snowflakes are an easy example of this. If you look at a snow flake you an see tiny feathery ice crystals are frozen together, giving it its flake-ish shape. Concentration is the amount of a substance per defined space. For example, when you put a drop of dye in some water, you can see the water turn a pale shade of that color. But if you put several drops of dye in the same amount of water, you can see a the water turn a more vivid shade of color. Another thing to know about is a solubility curve. As stated by www.saskschool.ca, a solubility curve is "a graph showing the relationship between solubility and temperature." Here is an example of a solubility curve published by http://scienceprojectideasforkids.com/2010/what-is-a-supersaturated-solution/. When looking at this graph you can figure out the relationship between sugar and temperature. When I went on this website, http://www.kentchemistry.com/links/Kinetics/SolubilityCurves.htm, I learned the different relationships to explain the graph above. The black line labeled "sugar" is the point at which the solvent is saturated (the water cannot dissolve anymore solute). That means that when the negative end of a sugar bonds with the positive end of a water molecule, the water molecules will take the sugar molecule away from the sugar crystal. When all the water molecules have bonded with all the sugar molecules, the solvent becomes saturated. Anything above the line is supersaturated (there is too much sugar for the water to dissolve and its just clumping to itself) and anything below is unsaturated (more sugar is able to dissolve). In 100g of water at zero degrees Celsius about 175g of sugar are able to dissolve in the solvent and at 80 degrees Celsius about 360g of sugar are able to be dissolved. Basically, the higher the temperature the more solvent the solute is able to dissolve.

     You will now demonstrate your knowledge of these terms by following a simple candy recipe and producing a batch of hard candy. You will be able to evaluate your work by the outcome of your candy. When finished you will know if you did well if your hard candy ends up hard, the color and flavor is even and consistent, and if the candy looks like candy.

Candy Lab: Post 2



1. Edited recipe retrieved on 12/9/13 and cited from: http://lorannoils.com/node/73

   Hard Candy Recipe

   Safety

     -HOT sugar is dangerous to come in contact with. Do NOT touch!
     -Heating implement in use. Use with CAUTION!
     -Wear lab appropriate safety clothing: goggles, aprons, gloves, hair tied back, no loose garments

   Ingredients

    -2 cups granulated sugar

    -2/3 cup light corn syrup

    -¾ cup water

    -1 tsp flavoring

    -liquid food coloring

   
   
    -large coffee can
    -bunson burner
    -stirring spoon
    -candy thermometer
    -cookie sheet
    -pastry brush

   ——

   Use of a candy thermometer is recommended

   Directions

     1.  In a large coffee can, mix together sugar, corn syrup and water. Stir over medium heat until sugar dissolves.
     2.  Insert candy thermometer, making certain it does not touch the bottom of the can. Bring mixture to a boil without stirring.
     3.  While cooking down the sugar mixture, scrape any sugar crystals that form on the sides of the pan with a wet pastry brush back into the main solution.  
     4.  Continue to cook, without stirring, until the temperature reaches 260º F; add drops of coloring until desired hue is achieved. Do not stir (boiling will incorporate color into syrup).
     5.  Remove from heat precisely at 300° F, or until drops of syrup form hard, brittle threads in cold water (hard crack stage). After boiling action has ceased, add flavor and stir. USE CAUTION WHEN ADDING FLAVORING TO AVOID RISING STEAM.
     6.  Carefully pour syrup onto a cookie sheet and spread out into a thin sheet before cooling.
     7.  Cool completely. Break sheet candy into small pieces. Store in airtight containers between waxed paper. Store hard candy in a cool, dry place. Do not refrigerate.