atomic structure Flashcards
what is an isotope?
an atom of the same element with the same number of protons and a different number of neutrons
what is an ion?
an atom that loses or gains electrons to become charged
what is the defenition of relative isotopic mass?
the mass of an atom of an isotope relative to 1/12 the mass of an atom of carbon-12w
define relative atomic mass
the relative atomic mas is the weighted average mass of an atom of an element relative to 1/12 the mass of an atom of carbon-12
define relative molecular mass
the weighted average mass of a molecule of a substance relative to 1/12 the mass of an atom of carbon-12
what is electron density?
the probabilty of finding the electron in a certain direction
what is the order of filling up orbitals?
1s , 2s , 2p , 3s , 3p , 4s , 3d , 4p , 4d
what is pauli’s exclusion principle?
electrons must have different spins
what is aufbau’s process?
we fill up the lowest empty energy levels
what is hund’s rule?
we half fill the orbitals of the energy with electrons of the same spin
what is ionisation energy?
the amount of energy required to remove 1 mole of electrons from 1 mole of gaseous atoms or ions
what factors affect ionisation energy?
charge on the nuclleus
distance of electron from nucleus
amount of shielding created by electrons
how does the nuclear charge affect ionisation energy?
more protons = more charge = more attraction = more energy needed to remove an electron = higher ionisation energy
how does atom size affect ionisation energy?
bigger distance = less attraction between electron+nucleus = less energy to remove electron = lower ionisation energy
how does shielding affect ionisation energy?
more shells = more shielding = less energy needed to remove electron = lower ionisation energy
