Phases & PressureGeneral Chemistry for Majors 2 LabHeat & Curves and Phase DiagramsLab Group Members: Gabrielle Coleman & Adjhanni HydeDue date: March 12th20211 |P a g e
Phases & PressureContents1Title:32Purpose/Hypothesis33Introduction34Equipment & Materials45Experimental Procedure46Data5-107Discussion108Conclusion109Analysis Questions11-1210Grading Criteria for Lab Reports132 |P a g e
Phases & Pressure1.Title:Heat Curves & Phase Diagrams2.Purpose:To understand how the temperature of Paradichlorobenzene change as heat is applied.To understand how the temperature of Paradichlorobenzene changes when they gothrough a phase change.3.Introduction:The following exercises will have you engage in applications of the concepts of statechanges.The first activity involves watching a video that demonstrates monitoringthe correlation between vapour pressure and temperature.Recall that this relationshipcan be represented through the Clasius Clapeyron equation: lnP= -Hvap/RT.By plotting the natural log of the pressure versus the temperature, the enthalpy ofvaporization can be estimated. The second activity allows you to see how a heatingcurve/cooling curve can easily be obtained by monitoring the temperature and thestate of a material as a sample is heated/cooled.The last exercise has you work withdifferent phase diagrams. We will be working on the activities during the lab session.After the session, students need to take a quiz in Moodle based on the informationcovered.3 |P a g e
Phases & Pressure4.Equipment & Materials:1.Bulb-holdsliquidEthylAcetate2.Ethyl Acetate-liquid used inthe experiment3.Boiling Chips-prevent bumping4.Heating Mantle- heat the Ethyl Acetate5.Thermometer- measures the boiling temperature6.Cold Finger- prevent acetate from escaping into the system7.Valve to external atmosphere- controls whether the acetate is connected to the rest of thesystem8.Ballast- used to hold the Ethyl Acetate vapor9.Valve to manometer- controls whether the manometer is reading the pressure of thesystem10.Digital Manometer- measures a differential between atmospheric pressure and pressureinside the system (vacuum from atmospheric pressure)11.Central Valve- controlled for experiment and has 2 lines that control whether the valve isopened or closed and for which side4 |P a g e
Phases & Pressure12.Variac – contains atmosphere pressure13.Vacuum pump- contains vacuum pressure5.Experimental Procedure:A video entitled “ Phase Change lab, heating and cooling curve” was watched.