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Structure of Matter1

Structure of Matter (Part 1 of 2)

ATOM Smallest part of an element Same physical and chemical properties Atoms combine to form molecules (H20)
ELECTRON Particle with a negative electrical charge; Almost NO atomic mass Moves at high speeds around the nucleus Different energy levels Number of electrons same as protons
ELECTRON SHELLS Specific energy levels Electrons are found here Move around the nucleus of an atom
ELEMENT A substance With only one kind of atom i.e., gold, carbon, oxygen
ISOTOPES Different atoms of the same element Same atomic number With different numbers of neutrons i.e., carbon-12 and carbon-14
MATTER Anything that has mass AND occupies space ALL matter made up of atoms
NEUTRON Found in the nucleus Uncharged particle with a neutral charge A mass equal to a proton
NUCLEUS Dense center of an atom Location of protons & neutrons
PROTONS Particle in the nucleus of an atom Has a “positive” electric charge Atomic mass of one Number of protons same as atomic number
RADIOACTIVE ISOTOPES Unstable isotopes Undergoes nuclear decay New element often formed i.e., Carbon 14
VALENCE ELECTRONS Electrons in the outermost (electron) shell of an atom To be stable NO more than 8 electrons in outermost shell
Radioactive (nuclear) decay Process by which an unstable atomic nucleus loses energy by emitting ionizing particles (ionizing radiation). The emission is spontaneous The nucleus decays without collision with another particle or atom
Created by: pj johnson