Earth is made mostly of rock. It has comparatively small amounts of liquid and gaseous components. The four innermost planets of the Solar System have this in common with Earth, while the outer, non-dwarf planets are all gas giants, in which gaseous elements comprise the vast majority of the mass of the planets.
The earth is made of mostly rock because the crust is rock and the inside such as the core is molten rock such as lava.
rocks
rocks
Gas
rocks
Rocks
Uranus is a gas giant, it has a rocky core but is mostly gas.
Mars is mostly rock
Jupiter is mostly made out of gas not rock.
I believe it is mostly gas.
rocks- mostly metamorphic
The Earth and the Moon are not made mostly of gas but the Sun is.