Look around you. Anything that we see, touch, or feel is an example of matter. Matter has different properties. In this lesson, we will learn about the physical and chemical properties of matter.
The qualities or attributes that make one matter different from another are called the properties of matter. Properties of matter are generally grouped into two categories: physical or chemical.
The properties that can be observed or measured without changing the composition of matter are known as physical properties. These are used to observe and describe matter. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity.
Physical properties are further classified as intensive and extensive properties, depending upon whether they are influenced by the size or extent of the matter.
An intensive property does not depend on the system size or the amount of material in the system. Some of the intensive property of an object include temperature, refractive index, density, and hardness. For example, when a diamond is cut, its pieces maintain their intrinsic hardness. In contrast, extensive properties are additive for independent, non-interacting subsystems. That is, the property is proportional to the amount of material in the system.
| TYPE OF PHYSICAL PROPERTY | DEFINITION | EXAMPLE |
| Intensive properties | A physical property that will be the same regardless of the amount of matter |
density: the measure of mass per unit volume color: the pigment or shade conductivity: electricity to flow through the substance malleability: if a substance can be flattened luster: how shiny the substance looks? |
| Extensive properties | A physical property that will change if the amount of matter changes |
mass: how much matter in the sample? volume: how much space the sample takes up? length: how long the sample is? |
Besides physical properties, the matter has chemical properties. A chemical property describes the ability of a matter to changes its identity after reacting with something else. These are behaviors that matter displays when it goes through a chemical change.
For example, if you leave your bicycle outside all summer, chances are it will start to rust. This occurs when the iron in metal reacts with oxygen and the moisture in the air. These conditions lead to the creation of iron oxide, which is the reddish-orange deposit we call 'rust'. The more general term for rusting is 'corrosion'. Iron is very hard and silver in color, whereas iron oxide is flakey and reddish-brown.
Besides the ability to rust, other chemical properties include reactivity and flammability.
Reactivity is the ability of matter to combine chemically with other substances. Some kinds of matter are extremely reactive; others are extremely unreactive. For example, potassium is very reactive, even with water. When a small-sized piece of potassium is added to a small amount of water, it reacts explosively.
Flammability is the ability of matter to burn. When matter burns, it combines with oxygen and changes to different substances. Wood is an example of a flammable matter. Fossil fuels, such as coal, natural gas, and petroleum, as well as fuels made from petroleum such as gasoline and kerosene are also flammable.
Chemical properties are very useful in identifying substances. However, unlike physical properties, chemical properties can only be observed as the substance is in the process of being changed into a different substance.
Here are some example of chemical properties
Everything that we see, touch, or feel is a matter - it is all around us. All matter have physical properties and chemical properties. Physical properties, such as density, mass, and volume, are those that can be observed or measured without changing the composition of matter. Chemical properties are properties that can be observed or measured only when matter undergoes a change to become an entirely different kind of matter.
