The âprodromal syndromeâ is not a diagnosis, but the technical term used by mental health professionals to describe a specific group of symptoms that may precede the onset of a mental illness. For example, a runny-nose is often âprodromalâ to (happening before) a cold, which means that a runny-nose may be a risk factor for developing this illness.
These are all that have importance in chemistry. There are some other very small particles, but they are studied by physicists in the field of nuclear particle physics. Electrons are the only particle involved in chemical reactions. Atoms form compounds using chemical reactions. 7 people found this useful.
Atoms are the smallest particles of matter that can enter into chemical reactions. Elements are composed of atoms. Molecules are the smallest particles of matter that can have independent existence. Molecules can contain one atom, two atoms, or more than two atoms. Atomic number is the number of protons in the nucleus of an atom of an element. Mass number is the sum of the protons and the neutrons in the nucleus of an atom of an element.