Atom Basics
Atom - answer The smallest unit of an element that maintains the properties of that
element.
Nucleus - answer The dense center of the atom which contains protons and neutrons.
Proton - answer A positively charged particle in the nucleus of an atom.
Neutron - answer A particle that has no charge and is found in the nucleus of an atom.
Electron - answer A negatively charged particle found outside the nucleus of an atom.
Atomic Number - answer The number of protons in the nucleus of an atom; the atomic
number is the same for all atoms of an element.
Relative Atomic Mass - answer The number of protons + the number of neutrons; the
average mass of all the isotopes of an element;
Ion - answer An atom that has gained or lost one or more electrons and has a negative
or positive charge.
Isotope - answer Atoms of the same element that have different numbers of neutrons.
Anion - answer An atom that has gained an electron and has a negative charge.
Cation - answer An atom that has lost an electron and has a positive charge.
Valence Electrons - answer Electrons on the outermost energy level of an atom
Atom - answer The smallest unit of an element that maintains the properties of that
element.
Nucleus - answer The dense center of the atom which contains protons and neutrons.
Proton - answer A positively charged particle in the nucleus of an atom.
Neutron - answer A particle that has no charge and is found in the nucleus of an atom.
Electron - answer A negatively charged particle found outside the nucleus of an atom.
Atomic Number - answer The number of protons in the nucleus of an atom; the atomic
number is the same for all atoms of an element.
Relative Atomic Mass - answer The number of protons + the number of neutrons; the
average mass of all the isotopes of an element;
Ion - answer An atom that has gained or lost one or more electrons and has a negative
or positive charge.
Isotope - answer Atoms of the same element that have different numbers of neutrons.
Anion - answer An atom that has gained an electron and has a negative charge.
Cation - answer An atom that has lost an electron and has a positive charge.
Valence Electrons - answer Electrons on the outermost energy level of an atom
