This explains why solids have a fixed shape. In a liquid like water, the particles are randomly arranged. They move freely over each other, a bit like marbles in a bucket.This is why liquids can ...

A 3D shape with regular polygonal faces, meeting at equal angles, is a platonic solid. There are five platonic solids, the tetrahedron, cube, octahedron, dodecahedron and icosahedron. A prism is a ...