atoms and reactions Flashcards
what is the atomic number of an atom?
the number of protons
what are isotopes?
atoms with the same number of protons and electrons, but different number of neutrons
what is the mass number of an atom?
the number of protons and neutrons
what is an ion?
a charged atom
what are cations?
positive ions
what are anions?
negative ions
what is mass defect?
the strong nuclear force holding together protons and neutrons comes at the expense of the loss of a fraction of their mass
what does “relative isotopic mass” mean?
the mass of an isotope compared to 1/12th of the mass of an atom of carbon-12
what does “relative atomic mass” mean?
the weighted mean mass of an atom compared to 1/12th the mass of an atom of carbon-12
what does the weighted mean mass take into account?
- the percentage abundance of each isotope
- the relative isotopic mass of each isotope
what is Avogadro’s constant?
6.02× 10²³ mol-1, the number of particles in each mole of carbon-12
what does empirical formula mean?
the simplest whole number ration of atoms of each element in a compound
what does molecular formula mean?
the number of atoms of each element in a molecule
what does “relative molecular mass” mean?
compares the mass of a molecule with the mass of an atom of carbon-12
what is a standard solution?
a solution of known concentration
