In a Rutherford scattering experiment, α\alphaα-particles are fired at a thin gold foil in a vacuum. Most α\alphaα-particles pass straight through, but a very small fraction are deflected by angles greater than 90∘90^\circ90∘.
What does the observation of these large-angle deflections provide evidence for?
The presence of neutrons in the nucleus.
Most of the atom's mass is distributed evenly throughout its volume.
The existence of a tiny, dense, and positively charged nucleus in each atom.
The existence of orbiting electrons in discrete energy levels.
284 exam-style questions on CIE IGCSE Physics 5.1 The nuclear model of the atom, covering 5.1.1a Structure of the atom and ions, 5.1.1b Alpha-particle scattering, 5.1.2a Composition of the nucleus and isotopes, 5.1.2b Proton number, nucleon number and nuclide notation, and 5.1.2c Nuclear fission and nuclear fusion. Each one has a worked solution and a mark scheme showing where the marks go.