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1.1 Elements of Life
Atoms are made of three types of sub-atomic particles protons, neutrons and electrons.
Protons and neutrons form the nucleus of the atom and electrons move around it.
The nucleus is tiny in comparison to the space occupied by the electrons.
Particle Mass on a relative Charge relative to Location in atom
atomic scale neutron
Proton 1 +1 In nucleus
Neutron 1 0 In nucleus
Electron 0.00055 -1 Around nucleus
History of the Atom