Caloric Content of Food Exercise 1: Determination of Caloric Content of Three Foods Abstract: First I gathered all the equipment needed. Then I zeroed out my balance and measured the mass of the empty beaker. I then put 50mL of water in the beaker and measured the mass again. I put a piece of foil at the bottom of my burner stand and then placed the beaker with water on the beaker stand. I then took the initial temperature of the water.
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.
Then weigh the crucible without the hydrate after heating. Record both masses. Next, add CoCl2 ∙6H2O and weigh the crucible. Now place the hydrate and crucible on the hot plate. Observe the color change while it is being heated.
Roast in the oven for about 20 minutes, until toasted but not burnt. Place the roasted vegetables, and soaked chile pods into a blender or food processor, along with salt and pepper. Puree until smooth. Step 5. Heat vegetable oil in a large skillet over medium-high heat.
Let it cook. Then use your oven mitts again and pull the tray out. Baste it with marinade using a brush or a spoon or something else but not your hand and put it back in the oven for 10 minutes. Let the juices run out. Don’t worry if the juices around the chicken starts burning.
While stirring, 6 M NaOH was added drop-wise until the solution became basic, turning red litmus paper blue. A total of 3.84 mL NaOH was required to achieve this; the resulting solution appearing dark blue with cloudy precipitates. The solution was then heated gently atop a hot plate to catalyze the next reaction, with care taken to assure all residue was kept off the walls of the beaker. Heating continued until the reaction reached completion and the solution slowly changed from blue to a dark green and finally black. At this point the heat was turned off to allow the black solid in the beaker, CuO, to settle to the bottom.
Slowly pour the beaker contents into the drip paper. Make sure every piece is out of the beaker. 10. Remove the funnel from the drip and the filter paper from the funnel. Allow the filter paper to dry overnight.
Allow the splint to burn until the color fades. Don’t let any solids to fall into the burner. -Soak the wooden splint in the “rinse water” to put it out completely; move it to trash. -Record observations on flame color produced by the metallic salt in the Data Table. -Repeat above steps (middle section) for all metallic salts (five total).
• 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.
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.