Question | Answer |
nucleus | in physical science, an atoms central region, which is made up of protons and neutrons |
electron cloud | The region of negative charge surrounding an atomic nucleus that is associated with an atomic orbital. |
proton | a subatomic particle that has a positive charge and that is located in the nucleus of the atom;the number of protons in the nucleus is the atomic number, which determines the identity of an element |
neutron | a subatomic particle that has no charge and that is located in the nucleus of the atom |
electron | a subatomic particle that has a negative charge |
atomic number | tells you how many protons are in an atom of the element |
average atomic mass | The average mass of atoms of an element, calculated using the relative abundance of isotopes in a naturally-occurring element. It is the weighted average of the masses of naturally-occurring isotopes |
mass number | the sum of the numbers of protons and neutrons in the nucleus of an atom |
molar mass | The mass of one mole of a substance |
molecular mass | A number equal to the sum of the atomic masses of the atoms in a molecule. The molecular mass gives the mass of a molecule relative to that of the 12C atom, which is taken to have a mass of 12. |
isotope | an atom that has the same number of protons (or the same atomic number) as other atomsof the same element do but that has a different number of neutrons (and thus a different atomic mass) |
ion | an atom, radical, or molecule that has gained or lost one or more electrons and has a negative or posotive charge |
cation | A cation is an ionic species with a positive charge. |
anion | An ionic species having a negative charge. |
mole | the SI base unitused to measure the amount of a subatance whose number of particles is the same a the number of atoms of carbon in exactly 12g of carbon-12 |
avagadro's number | Avogadro's number is the number of particles found in one mole of a substance. It is the number of atoms in exactly 12 grams of carbon-12. This experimentally determined value is approximately 6.022 x 1023 particles per mole. |