Assuming that almost all of an atom's mass is concentrated within its nucleus, and that the radius of a typical atom is approximately 105 10^5\,105 times larger than the radius of its nucleus, what is the order of magnitude of the ratio of the density of the nucleus to the average density of the atom?
10510^5105
101010^{10}1010
10−1510^{-15}10−15
101510^{15}1015
81 exam-style questions on Edexcel GCSE Physics 6.1 Atomic structure and isotopes, covering 6.1.1 Structure of the atom, 6.1.2 Isotopes: atomic and mass number, 6.1.3 Sub-atomic particles: masses and charges, and 6.1.4 Electron orbits and energy changes. Each one has a worked solution and a mark scheme showing where the marks go.