3.1a Substances have characteristic properties. Some of these properties include color,
odor, phase at room temperature, density, solubility, heat and electrical conductivity,
hardness, and boiling and freezing points.
3.1b Solubility can be affected by the nature of the solute and solvent, temperature, and
pressure. The rate of solution can be affected by the size of the particles, stirring,
temperature, and the amount of solute already dissolved.
3.1c The motion of particles helps to explain the phases (states) of matter as well as
changes from one phase to another. The phase in which matter exists depends on the
attractive forces among its particles.
3.1d Gases have neither a determined shape nor a definite volume. Gases assume the
shape and volume of a closed container.
3.1e A liquid has definite volume, but takes the shape of a container.
3.1f A solid has definite shape and volume. Particles resist a change in position.
3.1g Characteristic properties can be used to identify different materials, and separate a
mixture of substances into its components. For example, iron can be removed from a
mixture by means of a magnet. An insoluble substance can be separated from a soluble
substance by such processes as filtration, settling, and evaporation.
3.1h Density can be described as the amount of matter that is in a given amount of
space. If two objects have equal volume, but one has more mass, the one with more
mass is denser.
3.1i Buoyancy is determined by comparative densities.