Question

In the extraction of caffeine from an energy drink lab, ice-water is added to a test tube (in a heated flask of caffeine) in order to sublimate the caffeine. What would have happened if we put ice-water in the tube, before the hot plate had reached a very hot temperature?

Answer 1

In the extraction of caffeine from an energy drink lab, ice-water is added to a test tube (in a heated flask of caffeine) in order to sublimate the caffeine.

In the flask, the temperature is very high so caffeine will change its physical state from solid to vapours. These vapours will condense on the outside walls of cold test tube.

If we put ice-water in the tube, before the hot plate had reached a very hot temperature, the temperature inside the flask will not be high enough to cause sublimitation. Thus, no sublimation will occur.