According to current speculation, Jupiter probably has a small, solid core of silica.
Above that lies a shell of a different form of liquid hydrogen.
Jupiter’s core is surrounded by dense metallic hydrogen, which extends outward to about 78 percent of the radius of the planet.
Droplets of helium and neon precipitate downward through this layer, resulting in reduced quantities of these elements in the upper atmosphere.
Above the liquid lies 600 miles (960 km) of mostly hydrogen and helium gas, with some methane, ammonia, neon, oxygen, phosphine, and other gases.
The size of Jupiter ensures enough gravity to keep the gases in orbit.