BTEC Level 3 Applied Science Unit 2 LAB

BTEC Level 3 Applied Science Unit 2 LAB. BTEC Level 3 Applied Science Unit 2: Practical Scientific Procedures and Techniques Learning Aim B: Undertake calorimetry to study cooling curves Introduction The aim of this practical is that we are trying to contrast the rate of cooling between stearic acid and paraffin wax. Both paraffin wax and stearic acid have the same forces of attraction between them. The higher the temperature, the higher the kinetic energy of these molecules and the faster they move around and as the molecules move slower, the forces of attraction will be greater as they will be forming bonds. I will be calibrating the thermometer as I will be check the temperature through boiling water, ice cold bath and room temperature. Equipment list  Beaker  Boiling tube  Thermometer  Stop clock  Clamp, stander  Bunsen burner  Heat resistant mat Drawing of my set up Results table of calibration of the thermometer (practice recording temperatures) Time (sec) Temperature 0 20 This study source was downloaded by from CourseH on :41:51 GMT -06:00 Yusuf 60 80 120 79 180 78 240 77 300 76 360 75 420 74 480 73 540 72 600 71 Calibration of cold water and boiling water Cold water Temperature 1 st 19o C 2 nd 19o C 3 rd 19o C Boiling water Temperature 1 st 98o C 2 nd 99o C 3 rd 100o C Safety precautions Bunsen burner- keep away from distance when heating the substance, which is paraffin wax and stearic acid Boling water- when picking up the boiling test tube, use tongs to pick the hot boiling test tubes containing the substance. Method 1. Put about 150 cm3 water into the beaker. 2. Heat it on a tripod and gauze until the water just starts to boil. 3. Set up the apparatus as shown in the diagram and start the timer. Keep the water boiling, but not boiling vigorously. 4. Using a suitable results table, record the temperature of the stearic acid every minute until it reaches about 70˚C. Note on your results table the point at which you see the solid start to melt. 5. Use the clamp stand to lift the tube from the hot water. Record the temperature every minute as the stearic acid cools down until it reaches about 50˚C. Note on your results table the temperature at which you see the stearic acid begin to solidify. Results table for Paraffin Wax