atoms, ions, and compounds

what is an isotope?

atoms of the same element with different numbers of neutrons with the same number of electrons and protons

why do different isotopes of the same element react in the same way?

neutrons have no effect on the reactions of an element
chemical reactions only involve electrons; isotopes have the same number of electrons in the same arranagement

what is the unit used to measure atomic masses called?

unified atomic mass unit, u

what is relative isotopic mass?

the mass of an isotope relative to 1/12th of the mass of an atom of carbon-12

the relative isotopic mass is the same as which number?

the mass number of the isotope 

what two assumptions are made when calculating the mass number?

the contribution of the electron is neglected, mass of both proton and neutron is taken as 1u

what is relative atomic mass?

the weighted mean mass of an atom of an element relative to 1/12th of the mass of an atom of carbon-12

what does ‘weighted mean mass’ mean?

it takes into account the percentage abundance and relative isotopic mass of each isotope

what are the uses of mass spectrometry?

identify unknown compounds, find the percentage abundance of the isotopes in a sample of an element, determine structural information

how does a mass spectrometer work?