Question

A pharmaceutical company produces camphor for medical use. They thoroughly dry the solid under vacuum before sublimation. They analyze the product by melting pt to determine the amount of isoborneol impurity. A new manager decides the drying process takes too long, and insists the product be sublimed and analyzed before it is fully dry. a. How will this affect final melting point b. will the mass percentages calculated be accurate? why or why not

Answer 1

a. If the sample is not fully dry prior to sublimation, the observed melting point would be lower than actual value. Impurities will weaken the intermolecular bonds between individual molecules in solid and thus the compound would require less heat to convert to liquid state that is to melt the compound.

b. The mass percentage thus calculated will have error in it and would be higher than the actual value. As the amount of water will also be measured here, the mass percentage will be actual value + mass of water present in the sample.