Explain why this difference between the inner and outer core's density exists?

Metals and the frequency in which they're found influences a lot since different metals have different densities. Heat also influences a lot since hotter things tend to be less dense though the inner core is more dense.

The inner core is more dense because it's liquid and hotter, and since it's liquid the earth's movement makes it difficult for the inner core to be less denser than it is.

Hope it helped,

BioTeacher101

rain is the best answer

where is the scientific experiment?