There are many more examples. Note that measuring each of these properties will not alter the basic nature of the substance. Examples of chemical properties are: heat of combustion, reactivity with water, PH, and electromotive force.
Mathematical fonts. In mathematical mode you can change the typefaces of the fonts when needed. For instance, it's customary to represent real numbers with a blackboard bold font, or topological spaces with calligraphic font. This article shows several fonts in math mode.
The distinction between font and typeface is that a font designates a specific member of a type family such as roman, boldface, or italic type, while typeface designates a consistent visual appearance or style which can be a family or related set of fonts.