Developing Metals Flashcards
Describe d-block elements.
Putting an electron into a 3d orbital gives a lower energy than filling the 4s orbital.
Cr and Cu have different electronic configurations.
What colours are produced by Fe2+, Cu2+, Au, Mn3+, Cd2+, Co2+ and Pb2+?
Fe2+ green Cu2+ blue Au red Mn3+ purple Cd2+ mustard yellow Co2+ blue Pb2+ yellow.
Describe how transition metals are used as catalysts.
Use 3d and 4s electrons to form weak bonds with reactants through chemisorption.
Describe Ramen spectroscopy.
A wavelength of coloured light is shone on a material. Small portion of energy bounces off at a different frequency, lost some energy and have a different colour.
Describe the addition of NaOH and NH4 to Fe2+, Fe3+ and Cu2+.
+NaOH
Fe2+ green
Fe3+ brown
Cu2+ blue
+NH4
Fe2+ redissolves, brown
Cu(OH)2 redissolves blue-purple copper/ammonia complex.
What factors is colour dependent on?
Number of d electrons, arrangement of ligands, the nature of ligands.
What are the complementary colours for purple, red, orange and yellow?
Purple - green.
Red - turquoise.
Orange - blue.
Yellow - violet.
Define ligand.
Negatively charged ions surrounding a metal atom.
How do ligands attach?
Coordinate bonding.
Describe the reactions of Vanadium.
V(5), yellow > V(4), blue > V(3), green, > V(2), violet.
What establishes the coordination number?
The number of ligand bonds.
Describe EDTA.
Ethylenediaminetetracetate is hexadentate/multidentate.
Antidote in metal poisoning (chelation). Removes Ca2+ ions from hard water.
Ethanedioate ion is a bidentate ligand.
Describe haemoglobin.
Multidentate ligand.
What are the prefixes for chloride, cyanaide, hydroxide, oxide, water and ammonia ligands?
Chloro, cyano, hydroxo, oxo, aqua, ammine.
Define potential difference.
Measure of how much each electrode is releasing or accepting an electrode.
Describe the effect of equilibrium on potential difference.
Equilibrium on the right indicates a greater electrode tendency to accept electrons, morepositive electrode. potential.
Describe standard electrode potential.
Hydrogen half cell used comparatively, 0V.
Describe rusting.
Corrosion is greatest where O2 is limited. Edges of droplet of water has the highest O2 concentration. Electrons needed to reduce oxygen come from the oxidation of iron.
A more negative electrode shifts equilbrium to the right, preventing formation of Fe2+.
Oxidation occurs at the anode. Making the iron a cathode will prevent corrosion.
Describe sacrificial metals.
A metal with a more negative value than iron can be used to protect iron from rust. Galvanised steel has a protective coating of zinc.
Describe an impressed current.
Applied with an emf, a negative terminal is connected to the metal, the metal is connected to a corrosive-resistant electrode, oxidising water instead.
