Niaboc67 said:
This notion perplexes me. Could I please have this explain with an example(s). I am confused are atoms not made up of the same protons and neutrons which are just essentially negatively or positively charged particles which are made of quarks? Which as confusing as that can become. How can one atom be unique from the others when they are made of the same negatively and positively charged particles?
Thank you
I think you are getting confused because you don't understand atomic structure.
An atom is made up of a nucleus, which can contain one or more protons (positively charged), and zero or more neutrons (no charge). Outside the nucleus, there is a group of much lighter particles called electrons (negatively charged).
Early models of the atom had the electrons orbiting the nucleus, much as planets orbit the sun, but later research has shown that those early models don't accurately reflect the true structure of the atom. The orbital paradigm persists because it simplifies the teaching of elementary chemistry.
Each element contains a unique number of protons in its nucleus. Hydrogen is the simplest element, because its nucleus contains just one proton. Helium is next, with two protons, all the way up to uranium with 92 protons. The number of protons in the nucleus of an atom is also called the atomic number.
The nucleus of an atom may also contain a certain number of neutrons. If two atoms of an element contain different numbers of neutrons in the nucleus, then you have different isotopes of the same element. For example, hydrogen has three isotopes: H
1 contains a single proton in the nucleus, H
2 contains a proton and a neutron, and H
3 contains a proton and two neutrons. These are all forms of hydrogen because each nucleus has only one proton.
The chemical properties of an element are determined by the arrangement of the electrons surrounding the nucleus. The electrons arrange themselves in a certain order, depending on their total number. Each atom of an element contains the same number of electrons as it has protons in the nucleus. The number of electrons in the outermost positions determine if an element is very reactive (like sodium or potassium) or relatively inert (like lead).
All atoms of hydrogen will react chemically in the same way. All atoms of lead will react chemically in the same way. Lead and hydrogen will react differently chemically, because the arrangement of electrons is different in lead from the arrangement of electrons in hydrogen.
Things like quarks play no role in the chemistry of an atom, beyond making up the protons and any neutrons in the nucleus. Quarks are thought to be the constituent parts of protons, neutrons, and other subatomic particles.