1
anything that has mass and occupies space
Matter
when two or more atoms combine
molecule
part of the universe you focus your attention on (think: the _____ of study)
system
tiny dense center of the atom
nucleus
tiny particles that make up matter
atoms
capacity to move, do work, change matter, produce heat
energy
everything in the universe outside of the system
surrounding
number of protons in the nucleus
atomic number
simplest form of matter with a characteristic set of properties
element
the energy of an objects motion (______ energy)
kinetic energy
positively charged subatomic particle found in the nucleus of the atom
proton
number of protons and neutrons in the atom
atomic mass
one or two letters that represent an element
chemical symbol
energy stored in the chemical bonds of a substance (______ _______ energy)
chemical potential energy
neutral charge subatomic particle found in the nucleus
neutron
an arrangement of elements in which the elements are arranged into groups and periods based on their properties
periodic table
a characteristic of a substance that can only be observed or measured when it changes into a completely different substance
chemical property
total kinetic energy of the atoms of a substance (_____ energy)
thermal energy
negatively charged subatomic particle found outside of the nucleus
electron
the scientific study of matter, its properties, composition, structure, and the changes it undergoes during reactions
chemistry