name PROP 507: Determining Molar Mass by Freezing Point Depression in Naphthalene Erica Goho Pre-Laboratory Assignment 1. What precaution should you take with naphtha- lene? avoid eye contact + Skin, in fume hood 2. Briefly explain why there is a constant-tempera- ture plateau in the cooling curve in Figure 1 but not in Figure 2. a because figure 2 has para-dichlorobenzene in the naphthalene 3. Briefly explain why, in Figures 1 and 2, the tem- perature rises immediately after the first crystals appear. because 4. If you could only record a single temperature reading in a freezing point determination experiment, which temperature should you record? (This is the point that you should observe most carefully when carrying out the experiment.) The water 5. Briefly explain why it is important for the beaker of water to cool slowly and for you to stir the naphthalene liquid as it cools 2.0 3.0 it is creating 4.0 reaction 5.0 6.0 7.0 8.0 9.0 6. Pure benzophenone freezes at 48.1 C. A solu- tion of 1.25 g of biphenyl