Chromatography Lab

Sahomy Rodriguez                                                    October 16, 2013

    5th period                                                                     H-18

                Paper Chromatography Lab (Seperating Mixtures)

• Pre-Lab:

1. What colors are mixtures?

Pink is a mixture of red and white as green is also a mixture of green and yellow.

   2.  What substances could be use to separate a mixture?

Substance that can be used to separate a mixture is H20, oil, alcohol, and bleach.

   3.  What is Paper Chromatography?

Chromatography is a method for analyzing complex mixtures (such as ink) by separating them into the components from which they are made up of.

   4.  What is the set up for Paper Chromatography?

•  Hypothesis Questions:

1. Are colors mixed to make other colors?

Yes because colors such as purple is a mixture of blue and red.

   2.   Can mixed colors separate into their component colors?

Yes by using the method of paper chromatography.

   3.   Can black separate into it's component colors? Which colors will it separate out to?

I believe black can separate into it's component colors which most likely be gray, white, and primary colors such as red, yellow, and blue.

• Materials:

-Goggles  

-Green and Black Markers 

-Strips of Filter Papers

-Metric Ruler

-Plastic Cup 

-Rubbing Alcohol

-Tape 

-Pencil

• Procedure:

1. Using the ruler, cut the filter paper into long, rectangular strips, about 3 cm x 10cm. *You need 2*
2. Measure 0.5 cm from the bottom of the paper strip and draw a horizontal line with your pencil across the width of the strip. Then, use the black marker to make a dot on the pencil line.
3. Tape the paper strip around the pencil so that the very bottom of the strip touches the alcohol. **Do not let ink dot touch alcohol
4. Pour rubbing alcohol into a plastic cup to a depth of ½ cm. Then, rest the pencil on the rim of the cup so that the end of the pencil strip with the ink mark is just barely in contact with the alcohol.
5. Observe for about 8 minutes.
6. Let the strip dry by taping it to a piece of paper provided.  Put group names, period, and ipod # on the sheet.
7. Repeat the process for the other solution for the same marker.

• Data:

Observations	Observation at 3 minutes	Observation at 6 minutes	Dry test strips
(Sharpie) Black marker w/ alcohol	Ink is rising/fading.  Solvent is slowly rising.	Gray purple and blue is separating from the mixture.	The mixture faded into the component shades of gray, dark blue, and purple.
Black marker with bleach	Solvent is quickly rising.	Still no change.	No components rised.
Black marker w/ H2O	Nothing has happened no rising occurring.	Again, nothing. No difference.	The mixture sample stayed in the same condition with no visible components.

•  Analysis and Conclusion:

1. What appeared on the filter paper? Describe all results.

Alcohol Test - This test was the only that separated the black into a gray, purple, and blue.

Water Test - This substance did not separate the mixture at all.

Bleach Test - The black did not separate with bleach either.

   2.  What did the results indicate about the black ink? What classification of matter would you give the ink?

The results indicated that the black ink is made up of different colors which absorb wavelengths and reflect others and this makes it evident that the black does not reflect anything. The ink is classified as a liquid and does not separate with every solvent. Therefore the sharpie marker's ink would be classified as not water-soluble which means it can't be dissolved in water. (Sources= http://www.sciencefriday.com , http://www.scientiareview.org/pdfs/167.pdf)

   3.  Is chromatography a useful separation method for separating ink mixtures? Explain based on your results.

Based on my results chromatography is a useful method for separating ink mixtures. Chromatography is a easy way to separate ink mixtures as I did with a black dot of a sharpie marker and alcohol. This solvent separated the mixture rapidly.

   4.  If you could alter the experiment to test another condition or factor, what would you change or test?

If I was able to alter the experiment I would've let the filter paper in each solvent in longer so all the components can show through adsorption and with more time the mixture on the filter paper in bleach would've separated.

• Post Lab:

1. How does paper chromatography work? What do the results tell us?

 A - Preferential adsorption of chemical compounds (gases or liquids) in an ascending molecular-weight sequence.

Egg Drop Lab

Sahomy Rodriguez  ( H18 )                                                                                September 12, 2013                                                                 Partner: Genesis Quinonez                                                              

                                                                      Egg Drop Lab

Initial Design:                                    

               
     Hypothesis                                              Materials List                              Procedure
This structure will protect an egg             - cotton balls                My partner and I were going to               from a 20 ft throw.                                 - rubber bands           construct the structure by tieing the sticks
                                                                - shish kabob sticks    together into a pyramid. Secondly, put                                                                     - soft industrial wire   the egg in a pantyhose with cotton balls,
                                                                 - old pantyhose         tie the ends and tie it to the sticks. Lastly,
                                                                                                   cover the pyramid in a circular/sphere
                                                                                                   like shape so if the structure drops it will
                                                                                                           roll instead with the soft wire.
                                                                                                               

Data:

I thought the initial design was going to weigh too much in grams. So we changed our design and created a new structure from inspiration of a youtube video that shows a plastic bucket filled with cotton balls, secured with a lid and duck tape saved an egg from a 30 ft drop.
Mass of Structure w/o egg - 93.67 grams
Calculation - 2000/93.67 *10    


Total - 213 points = A :)
Mass of Structure with egg - 153 grams

Results:

Test 1 - I dropped the structure from standing on the tables in the H room which is about 11 ft. The egg was safe.

Test 2 - My partner Genesis threw the structure from the same location on top of the table and the egg again, survived.

Test 3 - Ms. Janik tossed the structure up high about 20 feet in the hallway and the egg survived once again after all those tests.

Post Lab Questions:

1.) Our final design was created with 4 rectangular pieces of a sponge, rubber bands, a plastic container, cotton balls, and a Styrofoam cup. We created a base in the container with cotton balls. Secondly, placed the cup on top of the base and surrounded the outside of the cup with the pieces of sponges. Then, put cotton balls in the cup as a base for the egg, placed the egg on top, covered the egg with more cotton balls, and covered the container with it's lid. Lastly, I secured the container by rubber bands round it holding the container with the lid shut.

2.) Our design was changed to this structure after thinking thoroughly about the initial design. We thought the initial designs' mass would just equal up to too much.

3.) The purpose of having multiple test drops of out structure was to make sure our structure would survive the final, graded test. So we would able to improve our structure and create a hypothesis.

4.) I believe my structure held the egg and protected it well with the use of protection and placement to hold the egg and keep it in place.

5.) If I could change my design in any way I would change it's mass. If the egg broke i would've gotten 10 points and gotten the lowest grade. But my fear of not enough protection held me back from reducing it's mass.