Atomic number and mass number
Atomic number and mass number
The atomic number, ZZZ, is the number of protons in the nucleus. It identifies the element because every atom of a particular element has the same number of protons.
Step-by-step lessons on AQA GCSE Physics 4.1.2 Mass number, atomic number and isotopes. Each one builds up to exam-style questions. Build a strong grip on equations, units and Key Stage 3 fundamentals before tackling the more demanding topics like electromagnetism, the particle model of matter and space physics.