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Properties of Magma (pages 205–208). Physical and Chemical Properties (pages 205–206). Learning Objectives . Identify some physical and chemical properties of matter. Explain why some liquids flow more easily than others. Explain what factors determine the viscosity of magma.
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Properties of Magma (pages 205–208)
Physical and Chemical Properties (pages 205–206)
Learning Objectives Identify some physical and chemical properties of matter. Explain why some liquids flow more easily than others. Explain what factors determine the viscosity of magma.
Key Concept: Each substance has a particular set of physical and chemical properties. These properties can be used to identify a substance or to predict how it will behave.
Like other substances, magma has a certain set of properties, or traits. Properties can be physical or chemical.
Physical properties are traits that can be observed without changing what a substance is made of. Examples of physical properties are hardness and color.
Chemical properties are traits that can be observed only by changing what a substance is made of. An example of a chemical property is being able to burn. Another example is being able to combine with other substances.
Circle the letter of an example of a physical property. a. being able to burn b. being able to combine with other substances c. Hardness
true or false? You can observe a chemical property without changing what a substance is made of. false
Physical properties Chemical properties
Objective 1: Identify some physical and chemical properties of matter.
Key Concept: Because liquids differ in viscosity, some liquids flow more easily than others.
Viscosity a physical property of liquids.How well a liquid flows depends on its viscosity.
A liquid with high viscosity is thick. It flows slowly. An example of a liquid with high viscosity is honey.
A liquid with low viscosity is thin. It flows quickly. An example of a liquid with low viscosity is water.
sentence true or false? Honey has higher viscosity than water. true
Objective 2: Explain why some liquids flow more easily than others.
Key Concept: The viscosity of magma depends upon its silica content and temperature.
Silica is a common substance in Earth’s crust. Magma contains silica. Magma that contains more silica has higher viscosity.
High-silica magma produces high-viscosity lava. This lava flows slowly. High-silica lava or magma cools to form rocks such as granite.
Low-silica magma produces low-viscosity lava. This lava flows quickly. Low-silica lava cools to form rocks such as basalt.
Very hot magma produces lava called pahoehoe (pah HOH eehohee)Pahoehoe has low viscosity. It flows quickly. It hardens into a rippled surface.
Cooler magma produces lava called aa (AH ah). Aa has high viscosity. It flows slowly. It hardens into rough chunks.