The surface is mostly covered in water, but compared the total volume of spherical earth, there’s fuck all water.
There’s a difference between water and liquid.
Not sure if the solid core has more mass than the mantle.
In any case, I’d say it’s like a balloon with something solid floating in the middle.
I don’t believe the “solid” core is solid in any sense of the word we can relate to; kinda like how Jupiters volume is mostly gas, yet 99% of that is at densities greater than the Mariana trench — where you would vaporize, and would feel more solid to us that anything we’ve experienced — and the “solid” core is more like a molten hydrogen liquid; hotter than the surface of the sun (but not hot enough for fusion).
But how liquid is the molten core? (I assume that’s where this poster was going)
The correct answer is we don’t know. There are novel (to us, anyway) states of iron, for example, that exist at extreme temperatures and pressures that have led scientists to postulate on the possible existence of a crystalized iron core, within the already solid inner core.
