Chapter 12 page 297
Because its molecules are held very close together, almost as close as those of a solid,
liquid matter does have a definite volume. If you pour 1 quart of orange juice into a 2-quart
bottle, it will not spread out to fill the bottle. Likewise, you couldn’t force the quart of juice into
a half-quart container.
You can pour water because the molecules have enough speed to vibrate over and
around each other. This movement of molecules lets a liquid flow and take the shape of its
container. Thus, orange juice poured into a glass will take the shape of the glass.
This text is problematic because it fails to explain many things about molecules and how they interact to
create properties that you can observe.
Here is a revised text, with detailed, highly explicit explanations. This text produces dramatically greater
student learning. All of the new ideas were designed to address gaps in students’ prior knowledge as well as
possible misconceptions about matter that they might have. Students who have been successful in high
school and college chemistry courses have read texts like these and then told me that they wish that they
had read this before taking their chemistry courses, because it makes everything so much more easily
understood.
LiquidsAll liquids are made of molecules. We’ll use water as an example. Here is a picture of
what some water molecules look like: