Chemistry Questions and Answers[Level A+] 2023

mass of an electron - -1/2000th of a proton -relative charge and relative mass of a proton, neutron, and electron - -proton: charge=+1 mass=1 neutron: charge=0 mass=1 electron: charge=-1 mass=1/2000th -atomic number - -the number of protons in the nucleus of an atom -mass number - -the sum of the number of neutrons and protons in an atomic nucleus -isotopes - -atoms of the same element with a different mass number and number of neutrons -what is used as the standard measurement of relative masses? - -carbon-12 -relative atomic mass - -the weighted mean mass of an atom of an element compared with one-twelfth of the mass of an atom of carbon-12 -relative isotopic mass - -the weighted mean mass of an atom of an isotope compared with one-twelfth of the mass of an atom of carbon-12 -the unit for "amount of a substance" - -mole -Avogadro number - -6.23 x 10^23 (number of particles per mole) -molar mass - -mass per mole of a substance (units= g/mol) -empirical formula - -the simplest whole number ratio of of each atom of an element present in a compound