In Bohr's atomic model, an atom consist of a nucleus that is positively charged and is being surrounded by electrons that are said to travel in orbits or circular manner around. It is compared to the solar system where the nucleus is equivalent to the sun and the electrons are the planets.
When water freezes it forms a lattice pattern and expands. Because the water forms a crystal lattice when frozen, it's volume increases because the water molecules take up a lot of space but they aren't very compact.
