Measuring melting points 0.0 / 5 ? ChemistryEnergeticsA2/A-levelAQA Created by: jamey_brewsterCreated on: 01-05-19 19:11 What will the range of the melting point be if the sample is very pure? Sample will melt over a low temperature range, at the same value as quoted in data books. 1 of 6 What will happen to the melting point if there are impurities present in the sample? Melting point will be lowered (due to disruption of structure) and sample will melt over a range of several degrees C. 2 of 6 Which two methods can be used to measure melting point? 1) Using an electronic melting point machine 2) Capillary tube (containing sample) strapped to a thermometer immersed in heating oil. 3 of 6 If method 2 is used, what must be true of the heating oil? Must have a higher boiling point than that of the sample (also low flammability). 4 of 6 Why is the tube heated slowly near the known melting point of the pure organic product? So that the exact temperature of melting can be determined. 5 of 6 Why might errors occur/results not be valid? The temperature reading on the thermometer/melting point machine may not be equal to the actual temperature in the sample tube. 6 of 6
Comments
No comments have yet been made