Learners Ideas and Misconceptions - Essentials of Chemical Education - page 16

Fig. 1.9 Part of a questionnaire concerning the “horror vacui” of students [ 14 ]
Especially the explanations for their answers show this:
- “Space between the particles cannot be empty, there cannot be nothing
- I cannot imagine there to be nothing
- If there is no air, there has to be a vacuum and this I cannot imagine
- Something has to be there, there is no place, where there is nothing
- The space cannot just contain nothing
- Something has got to be there” [ 14 ]
Apart from the introduction of smallest particles themselves it is important to
discuss the empty space between the particles when teaching the particle model.
A convincing experiment may be the evaporation of ethanol (E1.15). An empty
balloon is filled with 1-2 mL of ethanol and closed with a knot. Water is boiled in a
big beaker; the balloon is thrown into the boiling water: the balloon gets bigger and
bigger, 200-300 mL of ethanol vapor are formed. After taking the balloon out of the
water, the volume decreases to the former small amount of ethanol. Explaining the big
gas volume one has to point out that the movement of ethanol particles is increasing