What changes occur in the composition of the earths layers from the core to the surface?

Answer 1

1. inner core - solid ball of nickel-iron alloy
2. outer core - liquid nickel-iron alloy
3. mantle - solid plastic basaltic rock (plastic means very flexible and can "flow" under pressure)
4. ocean crust - solid brittle basaltic rock
5. continental crust - solid brittle granitic rock

Answer 2

no, its density decreases with its pressure as altitude above sea level rises. The composition remains the same but the quantity of air per unit volume decreases with height.

yes the atmosphere changes with elevation the ozone layer wich filters alot of infared radiation from the sun is made of O3 wich is toxic if we breath it vs O2 wich exist from the stratosphere down that we breath