Spec 8463
Revise AQA GCSE Physics 4.1 Atoms and isotopes with the question bank and revision guides.
Atoms are very small, having a radius of about 1 × 10-10 metres. • The basic structure of an atom is a positively charged nucleus composed of both protons and neutrons surrounded by negatively charged electrons. • The radius of a nucleus is less than 1/10 000 of the radius of an atom. Most of the mass of an atom is concentrated in the nucleus.
