(Nuclei are generally composed of positively charged protons and uncharged neutrons. )
Quantum is a relatively broad concept ~ it should refer to all kinds of particles studied by quantum mechanics, including protons, neutrons and electrons.
Particle is also a relatively broad concept ~ refers to all kinds of particles.
Ions are charged particles ~
Because of the quantum, the particle range is too large to be compared.
The smallest one that can determine the size is an electron ~
1. Molecules are the smallest particles that keep the chemical properties of substances (atoms and ions can also keep the chemical properties of substances). Atoms are the smallest particles in chemical changes.
For example, the smallest particle to keep the chemical properties of chlorine gas is D (chlorine molecule) (a, ClB, Cl-C, 2ClD, Cl2). The smallest particle that keeps the chemical properties of CO2 is CO2 molecule; The smallest particles that keep the chemical properties of mercury are mercury atoms. The smallest particles in this change of electrolytic water are hydrogen atoms and oxygen atoms.
In atoms: nuclear charge number (positively charged) = proton number = extranuclear electron number.
Relative atomic mass = number of protons
neutron number
Atoms are composed of nuclei and extranuclear electrons, while nuclei are composed of protons and neutrons. The three kinds of particles that make up atoms are protons (positively charged), neutrons (uncharged) and electrons (negatively charged). Do all atoms have protons, neutrons and electrons? (wrong! Generally, hydrogen atoms have no neutrons).
The relative atomic mass of an atom =112/c atom with an atomic mass. The unit of relative atomic mass is "1", which is a ratio. The unit of relative molecular mass is "1".
Because the charge carried by the nucleus is equal to that of the electrons outside the nucleus, and the electrical properties are opposite, the whole atom is not electrically neutral (that is, electrically neutral).