In Exercise 4A: Plant Pigment Chromatography, the experiment was demonstrated by the teacher. We needed a 50-ml graduated cylinder with 1 cm of solvent in the bottom. One piece of filter paper needs to cut, so that it touches the solvent. Cut the end to a point and draw a pencil line 1.5 cm above the point. A coin needs to be used to extract pigments from the spinach leaf cells.
Controlled Variables: Size of wood samples, tempter of fire, method of ignition, shape of wood samples. B. Materials: Lighter (torch) Wood such as (poplar, oak, pine) Stopwatch Water Chiminea C. Procedure: Buy wood such as (poplar, oak, pine) cut into identical shape/size. Use the lighter (torch) to burn the wood in the chiminea and time how long it burns. Do the process 9 times (3 trials for each piece of wood.)
EXPERIMENT: TECH 0704, Distillation, macroscale technique only, simple and fractional: Substitute a mixture of 25 mL ethanol and 25 mL water for the toluene/cyclohexane mixture. Record the temperature at 2 mL intervals of distillate. Use glass beads to pack the fractionating column. Construct a graph of temperature vs volume for each distillation in your lab notebook. Compare the efficiencies of the two distillation methods in your lab notebook.
Skip questions B, C, D, E and F in the lab manual, and answer these instead: A. What is the average % acetic acid in your vinegar sample? Standard vinegar is 5% acetic acid.How does your result compare with the standard? G. A 5.0 mL sample of vinegar was titrated with 7.2 mL of 0.55 M NaOH(aq). If the density of the vinegar solution is 1.00 g/mL, what is the mass percent of acetic acid present?
Then horizontally on the line I just drew I marked off 9 spaces 1.5 cm apart. On one sheet inside the spaces I marked B1, then B2 in the next space and so on for the FD&C food color dyes, at the end I marked KS and KG for Kool-Aid strawberry and grape. On the second sheet of Chromatography filter pater I did the same thing. I made a 1 cm line from the bottom and spaced it off in 1.5 cm spaces. I marked those with the Store Food Colors, the M&M colors and the unknown color.
• Try to find a day where there is little to no wind to conduct your experiment. • You may prepare your Schoenbein papers in advance or use as soon as ready. If you will be using them at a later time, be sure to store them in a ziplock baggie out of direct sunlight. • Place 50 ml (3 tablespoons + 1 teaspoon) of distilled water into the ziploc baggie containing the cornstarch and potassium iodide. Mix well.
All color observations were recorded and compared to the known behaviors of the focus metals. The next step to identifying the unknown compound solution involved chromatography. Two 20 x 10 cm pieces of chromatography paper were obtained, both labeled six times: five for each individual metal sample and one for the unknown sample. A capillary tube was then used to spot all samples onto their appropriate positions on both pieces of paper. Each paper was then rolled, stapled on the top to create a tube, and carefully placed into a 600mL beaker, one containing ~30mL of 6M HCl, the other containing ~30mL of 1.5M HCl.
6. Is it possible to light a candle without touching the flame directly to the wick? Why or why not? Materials • candle • matches • safety goggles • lab handout & pen • ruler • watch glass • 400 mL beaker • CO2 indicator solution (limewater) • 50 mL beaker (for indicator) Procedure My lab partner and I performed a series of experiments to investigate the chemistry of the burning of a candle. The teacher provided the following chemical equation to describe the burning, or combustion, in the candle: Hydrocarbon fuel + O2 ( CO2 + H2O The candle we used was a small, white emergency candle about 3.5 cm tall.
The dependent variable was the average time spent on the shape drawn within sixty seconds. The standardized variables were the type of pen and sharpie used, the size of the shape (circle) the termites were placed in, and the maximum time (60 sec.) given for the termites to be observed. There were two levels of treatment, which were red ink pen and red ink sharpie. The sample size was 100 termites and there were 5 replications for each level of treatment.
Read the absorbance at 20 second intervals from the start of the mixing. Then record your measurements on the table. After two minutes remove the tube from the spectrometer and visually note the color change. 6) Now mix the contents of tubes 4 and 5, transfer to a cuvette, and repeat your measurements for two minutes at 20 second