M2 ,, Atomic Structure And Isotopes Flashcards
Define an isotope?
Isotopes are atoms of the same element with different numbers of neutrons and same number of protons
Define mass number?
Total number of protons and neutrons in the nucleus
(Usually the bigger number)
Define the atomic number?
Number of protons/electrons in nucleus
Usually smaller number
Properties of particles found in atoms?
Current model of the atom consists of protons and neutrons in a dense nucleus and electron around nucleus in shells.
Define relative isotopic mass?
Mass of an atom of the isotope compared with 1/12th of the mass of an atom of carbon-12
Define relative molecular mass (Mr)?
Average mass of a molecule compared to 1/12th of the mass of one atom of carbon-12
Define relative atomic mass?
weighted mean mass of all isotopes of the element compared with 1/12th of the mass of an atom of carbon-12
Define relative formula mass?
Refers to substances with giant structures
Sum of atomic masses of all the atoms in the formula of the substance
Why do isotopes have similar chemical properties?
Cuz the have the same electronic structure
The may have slightly varying physical properties due to different masses
Relative atomic mass formula
= ( isotopic mass x abundance% ) + ( I x A% ) / 100