Atoms to Molecules Flashcards
Calculate E, wavelength of photons and electrons.
Reference fomulae on equation sheet.
Sketch 1D, 2D and 3D standing waves.
Refer to cheat sheet.
Sketch and indicate nodes in standing waves.
Refer to cheat sheet.
Sketch radial wavefunction for 1s, 2s, 3s and 4s orbitals.
Refer to cheat sheet.
Sketch radial probability density for 1s, 2s, 3s and 4s orbitals.
Square of wavefunction; starts at 0. Refer to cheat sheet.
Sketch the shapes of s, p and d orbitals.
Refer to cheat sheet.
Define n, l and ml.
Three quantum numbers:
n = determines the size of the orbital e.g. the 2s orbital is larger than the 1s orbital; only integer values from 1 up.
l = number of subshells; can only range from 0 to n - 1. For n = 2, l = 0 for s orbital and l = 1 for p orbital.
ml = describes the energy levels in a subshell.
Relate l to n and ml to l.
l to n:
l can only range from 0 to n - 1. For n = 2, l = 0 for s orbital and l = 1 for p orbital.
ml to l:
ml has integer values from -l to l (including 0) e.g. when l = 2, ml can equal: -2, -1, 0, +1, +2.
Calculate the energy of the H and H-like atom given the orbital.
Refer to reference formulae in equations sheet.
Calculate the energy and/or wavelength of a transition in a H-like atom using the initial and final energy levels.
Using triangle(E) equation under 'reference fomulae.' Transition is equal to the energy difference between energy levels.
Explain how atomic orbitals overlap to form the bonding and anti-bonding molecular orbitals.
Each molecule orbital contains a maximum of two spin-paired electrons. Bonds form because the energy if the electrons is lower in the molecule than it is in isolated atoms. Stability is conferred by electron delocalisation in the molecule as they are bound by more than one nucleus.
Demonstrate occupations of electrons in molecular orbitals for H2 and F2.
F2:
- sigma2s and sigma2s orbitals filled, 6 bonding electrons, 4 electrons in degenerate pi orbitals.
Calculate bond orders for H2 and F2.
B.O. = (No. of electrons in antibonding molecular orbital minus (-) no. of electrons in bonding molecular orbital)
DIVIDED by 2.
Use molecular orbital energy diagram to determine if a diatomic molecule is diamagnetic or paramagnetic.
Diamagnetism = paired electrons; pairing of electrons cancels magnetic field out.
Paramagnetism = unpaired electrons; creates tiny magnetic fields.
Unpaired electrons in MO graph looks like only one upward facing arrow. Two arrows indicates pairing of electrons.
