An unexpected color change or release of odor also often indicates a chemical change. For example, the color of the element chromium is determined by its oxidation state; a single chromium compound will only change color if it undergoes an oxidation or reduction reaction. The heat from cooking an egg changes the interactions and shapes of the proteins in the egg white, thereby changing its molecular structure and converting the egg white from translucent to opaque.
The best way to be completely certain whether a change is physical or chemical is to perform chemical analyses, such as mass spectroscopy, on the substance to determine its composition before and after a reaction. Privacy Policy. Skip to main content. Introduction to Chemistry. Search for:. Physical and Chemical Properties of Matter Physical and Chemical Properties of Matter Properties of matter can be classified as either extensive or intensive and as either physical or chemical.
Learning Objectives Recognize the difference between physical and chemical, and intensive and extensive, properties. Key Takeaways Key Points All properties of matter are either physical or chemical properties and physical properties are either intensive or extensive. Extensive properties, such as mass and volume, depend on the amount of matter being measured. Intensive properties, such as density and color, do not depend on the amount of the substance present.
Key Terms intensive property : Any characteristic of matter that does not depend on the amount of the substance present. Physical and Chemical Changes to Matter There are two types of change in matter: physical change and chemical change. Learning Objectives Identify the key features of physical and chemical changes. Key Takeaways Key Points Physical changes only change the appearance of a substance, not its chemical composition. Wool is another traditional material that has undergone innovation.
Investigate the properties of wool and how they link to its uses in the student activity Exploring wool fibre properties. Some other fascinating, less well known materials include nanofibres , biological materials and composites.
When we refer to the properties of a material, we are talking about features we can sense, measure or test. For example, if we have a sample of metal in front of us, we can identify that this material is grey, hard and shiny. Testing shows that this material is able to conduct heat and electricity and that it will react with an acid. It is important to decide if you are investigating the properties of a material or of an object.
For example, are you identifying the properties of a spoon an object , or are you looking at properties of the material it is made of, for example, stainless steel? Properties like shape and mass may be different for different objects, even when they are made of the same material.
Density is a useful property for making comparisons between different materials. Other properties of materials can include their viscosity and conductivity. A commonly talked about property is the state or phase of matter.
There are currently five different states of matter that have been identified: solids, liquids, gases, plasma and Bose-Einstein condensate. The last two of these are much less well known. It is important to note that the state of matter refers to the positioning and movement of the particles that make up a material and not the material itself.
You can learn more about states of matter in the article States of matter. A property is any attribute of an object. Colour, height, mass, density, smell, taste, temperature and texture are just a few examples of common properties we use on a daily basis. We can group types of properties into different categories. One way to group types of properties is by the type of information it provides about an object.
For example, if I was holding an object behind my back and told you that the object I was holding had a mass of 1. The object I hold has a mas of 1.
You would have no idea what the object was because knowing the mass of the object does not help to determine the identity of the object. A property that depends on the amount of matter and does not depend on the identity of the matter is called an extensive property. Now, if I was again holding an object in my hand and told you that the object was an orange coloured metal that is a good conductor of electricity , would you know what the object is?
I have a copper coloured metal in my hand… what is the identity of the metal? You could probably make a very confident guess that I have a piece of copper in my hand.
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