The outer core behaves more like a liquid because S-waves from earthquake shocks reaching this zone are not transmitted through this zone at all.

As regards chemical composition of inner core, hyposis that it is made up chiefly of iron and nickel elements has found support from many accounts.

The mantle extends up to depth of 2900 km and from that depth it is core that is said to be present and radius of Earth is 6371 km and hence core is said to extend till 6371 km.

Silicon and Magnesium. The C-layer under continental crust is rich in Silicon and Magnesium and hence layer is also sometimes called SIMA.

It is said that exact nature of mantle is as yet incompletely understood.

The oceanic crust is estimated to have a volume of 2.54*109 cc with an average density of 3.00 g/cc.

The Asnosphere is believed to be located entirely in upper mantle and supports slowly moving tectonic plates.

At base of mantle, density is inferred as 5.7 g/cc that jumps to 9.9 g/cc at top of core.

SIAL stands for Silicon and Aluminium and as per name it is made up of two elements and hence name.

The A or upper layer is between 2 to 10 km thick and is of low density, 2.00 g/cc.