All properties of matter are either extensive or intensive and either physical or chemical. Extensive properties, such as mass and volume, depend on the amount of matter that is being measured. Intensive properties, such as density and color, do not depend on the amount of matter.
Solid, liquids, and gases : Water can exist in several states, including ice solid , water liquid , and water vapor gas. Physical properties are properties that can be measured or observed without changing the chemical nature of the substance. Some examples of physical properties are:. Physical properties : Matter has mass and volume, as demonstrated by this concrete block.
You can observe its mass by feeling how heavy it is when you try to pick it up; you can observe its volume by looking at it and noticing its size. Mass and volume are both examples of extensive physical properties. Here are several examples of chemical properties:. There are two types of change in matter: physical change and chemical change. Many physical changes are reversible such as heating and cooling , whereas chemical changes are often irreversible or only reversible with an additional chemical change.
Physical change : Blending a smoothie involves physical changes but no chemical changes. Another way to think about this is that a physical change does not cause a substance to become a fundamentally different substance but a chemical change causes a substance to change into something chemically new. Blending a smoothie, for example, involves two physical changes: the change in shape of each fruit and the mixing together of many different pieces of fruit. Because none of the chemicals in the smoothie components are changed during blending the water and vitamins from the fruit are unchanged, for example , we know that no chemical changes are involved.
Cutting, tearing, shattering, grinding, and mixing are further types of physical changes because they change the form but not the composition of a material.
Figure 3. Properties of matter fall into one of two categories. If the property depends on the amount of matter present, it is an extensive property. The mass and volume of a substance are examples of extensive properties; for instance, a gallon of milk has a larger mass and volume than a cup of milk. The value of an extensive property is directly proportional to the amount of matter in question.
If the property of a sample of matter does not depend on the amount of matter present, it is an intensive property. Temperature is an example of an intensive property.
As another example, consider the distinct but related properties of heat and temperature. A drop of hot cooking oil spattered on your arm causes brief, minor discomfort, whereas a pot of hot oil yields severe burns. Both the drop and the pot of oil are at the same temperature an intensive property , but the pot clearly contains much more heat extensive property.
You may have seen the symbol shown in Figure 4 on containers of chemicals in a laboratory or workplace. Figure 4. The system details flammability, reactivity, health, and other hazards. Within the overall diamond symbol, the top red diamond specifies the level of fire hazard temperature range for flash point. The blue left diamond indicates the level of health hazard. The yellow right diamond describes reactivity hazards, such as how readily the substance will undergo detonation or a violent chemical change.
Each hazard is rated on a scale from 0 to 4, with 0 being no hazard and 4 being extremely hazardous. While many elements differ dramatically in their chemical and physical properties, some elements have similar properties. We can identify sets of elements that exhibit common behaviors. For example, many elements conduct heat and electricity well, whereas others are poor conductors. These properties can be used to sort the elements into three classes: metals elements that conduct well , nonmetals elements that conduct poorly , and metalloids elements that have properties of both metals and nonmetals.
The periodic table is a table of elements that places elements with similar properties close together Figure 4. You will learn more about the periodic table as you continue your study of chemistry. The periodic table shows how elements may be grouped according to certain similar properties. Different elements or compounds are present at the end of the chemical change.
The atoms in compounds are rearranged to make new and different compounds. True or False: Bread rising is a physical property. True or False: Dicing potatoes is a physical change. Is sunlight matter? Introduction The different types of matter can be distinguished through two components: composition and properties. Physical Properties and Changes Physical properties can be observed or measured without changing the composition of matter.
Chemical Properties and Changes Chemical properties of matter describes its "potential" to undergo some chemical change or reaction by virtue of its composition. John Yossarian Wikipedia. Problems The following questions are multiple choice. Milk turns sour. Aluminum Phosphate has a density of 2. Which of the following are examples of matter? The formation of gas bubbles is a sign of what type of change? Solutions chemical change chemical property, physical change physical change physical property All of the above chemical False True No physical property.
References Petrucci, Bissonnette, Herring, Madura. General Chemistry: Principles and Modern Applications. Tenth ed.
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