Question

what is mean by crust ? give three points​

Answer 1

Crust” describes the outermost shell of a terrestrial planet. Earth's crust is generally divided into older, thicker continental crust and younger, denser oceanic crust. ... Earth has three layers: the crust, the mantle, and the core. The crust is made of solid rocks and minerals.

Answer 2

Question:-

• What is meant by crust? Give three points.

Answer:-

$\boxed{\rm{\red{Crust \longrightarrow }}}$

• The crust is the topmost layer of the earth.

• It is also called as $\sf\red{lithosphere}$

• It is the thinnest layer of the earth. The upper part of the crust is called the $\sf\blue{continental \ crust}$ and the lower part is called the $\sf\red{oceanic \ crust}$

• Continental crust is composed of silica (Si) and aluminum (Al) and hence is called as $\sf\green{sial}$. The average density of this layer is about $\sf\blue{2.7 \ g/cm³}$.

• Oceanic crust is composed of silica (Si) and magnesium (Ma) and hence is called as $\sf\green{sima}$. The average density of this layer is about $\sf\blue{3.0 \ g/cm³}$.

• The upper crust is a reservoir of minerals.

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Additional information:-

$\boxed{\rm{\orange{Mantle \longrightarrow }}}$

• The mantle is the middle layer of the earth.

• It is also called as $\sf\red{mesosphere}$

• It lies just below the crust. It is 2,900 km thick.

• The average density of the mantle ranges from $\sf\purple{3.5 \ to \ 5.5 \ g/cm³}$

• The mantle has two layers - the upper mantle and the lower mantle.

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$\boxed{\rm{\pink{Core \longrightarrow }}}$

• The core is the innermost layer of the earth.

• It is also called as $\sf\red{barysphere}$

• The average thickness of the core is 3,500 km.

• The temperature of the core ranges from 3,000°C to 5,000°C.

• The core has two layers - the outer core and the inner core.

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