Atomic Structure and the Periodic table Flashcards
What is an Atom?
The smallest particle of a chemical element that can exist. Atoms are the smallest building block of matter and make up everything in our universe.
what is an Element?
A chemical substance that cannot be broken down into other substances.
What is an atomic number?
An atomic number is a number given to an element that determines where it sits on the periodic table.
What is a mass number?
The total number of protons and neutrons in the nucleus of an atom.
Describe the structure of an atom.
An atom consists of protons and neutrons which reside at the center of the atom in what’s known as a nucleus. Far out from this are the electrons that orbit the atoms in what are known as electron shells. Atoms are mostly empty space.
What are protons?
A stable subatomic particle occurring in all atomic nuclei, with a positive electric charge equal in magnitude to that of an electron.
What are neutrons?
A subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
What are electrons?
A stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids.
What is a nucleus?
A small, dense region consisting of protons and neutrons at the center of an atom
What are the shells of an atom?
the outside part of an atom around the atomic nucleus
What is a valence electron?
A negatively charged particle, located in the outermost shell of an atom, that can be transferred to or shared with another atom
