In the last post I introduced the concepts of matter, mass, and composition. This post will be a brief introduction to properties of matter. Properties of matter can be defined as the unique, distinguishing, or defining qualities or attributes of a sample of matter that sets that sample of matter apart from others (Petrucci et al. 2010). Properties of matter are usually divided into the two subgroups of physical and chemical properties, which are discussed below.
Physical properties of matter are exhibited by a sample of matter without any change in composition. Some examples of physical properties of matter are color, odor, and density. For instance, copper is the color reddish brown, while sulfur is the color yellow. Some solids have the property of being malleable, such as copper, which can be flattened into a thin sheet of foil. This is not the same for sulfur, however, which when hammered for the purpose of flattening actually crumbles into a powder. Still, there are other properties that differentiate copper from sulfur. Another of these is ductility, which is the ability of a solid sample of matter to deform under stressful conditions by elongation. There are indeed other properties of these samples of matter that make them what they are and not like other samples of matter, but is not necessary to know a laundry list of said properties (Petrucci et al. 2010).
A sample of matter may also undergo a physical change, which changes one or more of the physical properties of the sample, but which leaves composition unchanged. A classic example of this is the transition of water to ice when frozen, such as in an ice cube tray. No matter what, unless something is added to the water, the composition of the water remains the same, even if the water now appears vastly different in its solid state (Petrucci et al. 2010).
Chemical properties of matter describe the ability of that sample of matter to undergo a change in its composition under a given set of conditions. A change in composition occurs with a chemical change, also known as a chemical reaction, and is thus a key identifying factor in a chemical change. An example of a chemical change occurs when paper is burned, and the ability of paper to burn constitutes a chemical property of the paper (a sample of matter). Just as chemical properties of matter involve the ability of a sample of matter to undergo a change in composition, the inability of a sample of matter to undergo a change in composition is also a chemical property. An example of this is gold's inability of react with hydrochloric acid (Petrucci et al. 2010).
As you go on to learn more about chemistry, you will find that the physical and chemical properties of different substances are very important. These characteristics of matter help scientists to determine the appropriate uses for a substance. For instance, zinc is nonreactive to water, and so it is used in roofing nails, roof flashings, and rain gutters, whereas sodium, which is reactive to water, is not used for these purposes (Petrucci et al. 2010). As you think about what you've learned in this post, try to come up with your own examples of defining physical and chemical properties of objects around you, in your home, and outside. This mental exercise will certainly help you solidify the concept you just learned as you apply your knowledge to the world around you.
A prospective medical student, looking to help others succeed.