How to explain the difference in the chemical composition of the terrestrial planets and giant planets?

The supposed reason is the spatial heterogeneity of the chemical composition of the protoplanetary cloud.

The inner group of planets. Terrestrial planets The outer group of planets. Giant planet
Weight From 3.3*10 ^ 23 kg (mercury) to 5.976*10 ^ 24 kg (Land) From 8,7*10 ^ 25 kg (Uranus) up to 1.9-1027 kg (Jupiter)
Size (Equatorial diameter) From 4880 km (mercury) to 12756 km (Earth) From 49,500 km (Neptune) to 143000 km (Jupiter)
Chemical composition Earth: Fe (34.6%), O2 (29.5%), Si (15.2%), Mg (1.7%) Mainly composed of gases: H2 (most of it), CH4, NH3
The presence of a solid surface All the planets of the earth group have a solid surface Do not have a solid surface
Number of satellites Earth-1, Mars-2, mercury-none, Venus-none Jupiter-14, Saturn-15, Uranus-5, Neptune-2
The presence of the rings Rings are missing The giant planets have rings
Speed

rotations around its own axis

Rotation around its axis is slow (compared to the giant planets) Rotation around its axis is fast (compared to the planets of the earth group)
Pluto, discovered later than the other planets (in 1930), can not be attributed to any of the groups.
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