Procedure the first step is to get the freezing point

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Procedure: The first step is to get the freezing point of pure naphthalene. Place 10 grams of naphthalene into a large test tube, recording the exact amount used. Heat it up using your Bunsen burner. After a while it will become a clear liquid. Heat it up to at least 100 degrees C. Place your digital thermometer into the liquid. Shut off the burner and take readings of the decreasing temperature of the naphthalene as a function of time, taking readings every 15 seconds. Stir the liquid as much as possible to evenly distribute the cooler material nearer the test tube walls to the inner center. This information will be posted in the data file. You will see a region where the slope of the curve flattens out for a while. This is because heat is being released as bonds are created when the liquid solidifies. This release of heat keeps the temperature constant during that time.
Small crystals will also form during this time. You will plot this temperature VS time information and determine the freezing point for each trial. There will be six different trials: Trial Description ------- ---------------------------------------------------------------------- A Pure naphthalene B Naphthalene with approximately 0.2 grams p -dichlorobenzene C Naphthalene with approximately 0.4 grams p -dichlorobenzene D Naphthalene with approximately 0.6 grams p –dichlorobenzene E Pure naphthalene (again) F Naphthalene with approximately 0.2 grams unknown To determine the actual freezing point for each trial, draw a line from this nearly flat region towards the temperature axis. The intercept of this drawn line with the axis is the freezing point. After you perform trial A, let the naphthalene cool down to room temperature. Next, for trial B, add approximately 0.2 grams of p –dichlorobenzene to the pure naphthalene. Record the actual amount used. Heat this up again to 100 degrees C and allow to cool, taking temperature readings every 15 seconds. Again, make a plot this data and determine the freezing point of this mixture again by drawing a line from the flat region to the temperature axis. Unfortunately, as the molality of the solution increases, the flat region may not be exactly flat. Just draw the best line that you can. The freezing point of this

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