Atomic Structure
No description yet. This curated deck is ready for daily study.
Card preview (24)
Series when n1 = 1?
Lyman UV n1 = 1 n2 = 2, 3 ,4…
Series when n1 = 2?
Balmer Visible n1 = 2 n2 = 3, 4 ,5…
Series when n1 = 3?
Paschen Infrared n1 = 3 n2 = 4, 5, 6…
Series when n1 = 4?
Brackett Infrared n1 = 4 n2 = 5, 6 ,7….
Series when n1 = 5?
Pfund Infrared n1 = 5 n2 = 6, 7, 8…
Ionisation energy of hydrogen?
Minimum energy required to completely remove the electron from an atom
What is the wave function?
Mathematical function that varies with position
What is the radial wave function R(r)?
Contains information about what happens to the wave function as distance from the nucleus increases
What is the angular wave function?
Contains information about the shape of the orbital
What is the Bohr radius?
The distance from the nucleus to the electron in the Bohr model off the hydrogen atom and is the most probably distance for finding the 1s electron from the nucleus in the quantum mechanical approach
What is R(r)^2?
Probability of finding an electron with a volume at a distance r from the nucleus - equivalent to the electron density at that point
What is the radial distribution function?
Most probable distance of finding an electron from the nucleus - the maximum in a radial distribution function represent the most probable distance fro the electron from the nucleus
Five d orbitals?
dxy dyz dxz dx^2-y^2 dz^2
Why does dz^2 have odd shape?
Schrödinger equation produces six solutions for l=2 but only five allowed values of ml, instead of throwing away a valid answer combine the two solution corresponding to dz^2-x^2 and dz^2-y^2 to give the dz^2 orbital
Aufbau principle?
Involves building up the electronic structure of an atom by filling the lowest energy orbitals first
Pauli exclusion principle?
No two electrons in an atom can have the same four quantum numbers - a maximum of two electrons can reside in any orbital
Hunds rule?
Ground state is the arrangement with the maximum number of parallel electrons
Scandium electronic configuration?
[Ar]3d1 4s2
Chromium electronic confirmation?
[Ar]3d5 4s1
Shielding?
In an atom with more than one electron there are electron repulsions as well as attractive interactions between nucleus and electron,t he repulsions shield electrons from full nuclear charge - charge felt by 2s electrons is less than actual charge due to shielding from 1s electrons. 2p electrons more effectively shielded than 2s electrons.
Penetration?
The presence of the radial node means there is an area of electron density relatively close to the nucleus for the 2s electrons - this electron density is largely absent for a 2p electron. 2s electrons said to penetrate 1s electrons, 2s electrons feels a higher efficient nuclear charge than a 2p electron. The 2s orbitals is stabilised more than the 2p orbital. S electrons more penetrating than p electrons and p electrons more penetrating than d electrons due to shapes of radial distribution functions.
Effective nuclear charge across a period?
Zeff felt by outermost electrons increases across a period, since electrons in the same shell do not shield etc other very effectively from the nuclear charge.
Atomic radius of element?
Half the distance between the nuclei of neighbouring atom in the pure element. If the element is a metal this becomes the metallic radius. If the element is a non metal this becomes the covalent radius
Atomic radius size trends?
Across a period decrease due to increasing Zeff pulling electrons closer to the nucleus and decreasing the atomic radius