Variable oxidation number (ion charge), coloured compounds, magnetic properties, form complex ions (a metal ion bonded to a ligand via a covalent bond)
increase down group 17, increase in the strength of London dispersion forces (because valence electrons held less tightly and form temporary dipoles more easily) with increasing number of electrons
When ligands bond to the central metal ion, repulsion between the electrons in the ligands and those in the d orbitals of the transition metal ion causes the five d orbitals to split into two sets of different energy (non-degenerate orbitals)
electrons can transition from the lower set to the higher set of d orbitals by absorbing energy, which are known as d-d transitions — we see the complementary colour of the light wavelength absorbed
When do transition metals (coloured complexes) absorb shorter wavelengths of light
ligands higher in the spectrochemical series produce a larger splitting of the d orbitals = takes more energy for electrons to make d-d transitions = absorbs shorter wavelengths of light
ions held together in crystal lattice structures (surrounded by ions of opposite charge) by ionic bonds, electrostatic attraction (mutual attraction between opposite charges)
formula expressed by simplest ratio
high melting point, soluble in polar solvents (water)
Covalent compounds (definition, what impacts bond length, what causes polarity, solubility)
form by the sharing of 2 electrons
Increasing number of bonds = shorter and stronger bonds
Polar bonds form when the two atoms bonded together have different electronegativity values (more than 0.5 difference) (exception: if molecular shape results in cancellation of polar bonds)
Like dissolves like — polar covalent soluble in polar solvent, non-polar covalent soluble in non-polar solvent