Which of the following layers is defined by its chemical composition?(1 point)
Responses
1) lithosphere
2) inner core
3) mantle
4) asthenosphere
The correct answer is the lithosphere. The lithosphere is the outermost layer of the Earth and is defined by its chemical composition, primarily composed of rocks and minerals. It includes the Earth's crust and a portion of the uppermost mantle.
To determine which of the following layers is defined by its chemical composition, you can examine the properties and characteristics of each layer.
1) Lithosphere: The lithosphere is the outermost layer of the Earth and is composed of both the crust and a portion of the upper mantle. It is defined by its physical properties rather than its chemical composition, as it includes both oceanic and continental crust, which can have different chemical compositions.
2) Inner Core: The inner core is the innermost layer of the Earth and is primarily composed of solid iron and nickel. It is not defined by its chemical composition alone, as its defining characteristic is being solid.
3) Mantle: The mantle is a thick layer located between the crust and the core. It is primarily composed of various silicate minerals, such as magnesium and iron silicates. The mantle is indeed defined by its chemical composition, making it a potential answer to the question.
4) Asthenosphere: The asthenosphere is a highly viscous, semi-fluid layer located beneath the lithosphere. It is composed of solid rock that can flow slowly over long periods of time. Like the lithosphere, the asthenosphere is not defined solely by its chemical composition.
Based on the explanations above, the layer defined by its chemical composition is the mantle (option 3).