Difference Between Physical and Chemical Properties

Difference Between Physical and Chemical Properties Measurable characteristics of matter may be categorized as either chemical or physical properties. What is the difference between a chemical property and a physical property? The answer has to do with  chemical and physical changes  of matter. A Physical Property A  physical property  is an aspect of matter that can be observed or measured without changing its chemical composition.  Examples of physical properties  include color, molecular weight, and volume. A Chemical Property A  chemical property  may only be observed  by changing the chemical  identity of a substance. In other words, the only way to observe a chemical property is by performing a chemical reaction. This property measures the potential for undergoing a  chemical change.  Examples of chemical properties  include reactivity, flammability and oxidation states. Telling Physical and Chemical Properties Apart Sometimes it can be tricky to know whether or not a chemical reaction has occurred. For example, when you melt ice into water, you can write the process in terms of a chemical reaction. However, the chemical formula on both sides of the reaction is the same. Since the chemical identity of the matter in question is unchanged, this process represents a physical change. Thus melting point is a physical property. On the other hand, flammability is a chemical property of matter because the only way to know how readily a substance ignites is to burn it. In the chemical reaction for combustion, the reactants and products are different. Look for Tell-Tale Signs of a Chemical Change Usually, you dont have the chemical reaction for a process. You can look for tell-tale signs of a chemical change. These include bubbling, color change, temperature change, and precipitation formation. If you see signs of a chemical reaction, the characteristic you are measuring is most likely a chemical property. If these signs are absent, the characteristic is probably a physical property.