| A | B |
|---|
| matter | anything that has mass and occupies space |
| atoms | fundamental building blocks of matter |
| element | the simplest form of matter that has a characteristic set of properties |
| chemical symbol | one or two letters that represent an element |
| molecule | two or more elements that have combined |
| energy | the capacity to do work, to move, to change matter, or to produce heat |
| kinetic energy | the energy of motion |
| thermal energy | the total kinetic energy of all the particles that make up matter |
| potential energy | the energy of position |
| chemical potential energy | the energy stored in chemical bonds |
| system | a portion of the universe that a scientist studies |
| surroundings | everything outside of a system |
| macroscopic property | a characteristic that is large enough to see, handle, or measure without magnification |
| neutron | a subatomic particle with no charge, a mass of 1 amu, and located in the nucleus of the atom |
| proton | a positively charged subatomic particle located in the nucleus of the atom |
| electron | a negatively charge subatomic particle |
| nucleus | the tiny, dense central portion of the atom, composed of protons and neutrons |
| atomic number | the number of protons in the nucleus of an atom of an element |
| periodic table | an arrangement of elements in which the elements are separated into groups based on a set of repeating properties |
| mass number | the total number of protons and neutrons in the nucleus of an atom |
| isotope | atom of the same element that have the same atomic numbe but different atomic masses due to a different number of neutrons |
| average atomic mass | the weighted average of the masses of the isotopes of an element |
