Fe3+ ; (1) NO3– (1)
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Transcript of Fe3+ ; (1) NO3– (1)
Identify all the species in the table which could convert I–aq) into I2(aq) but which could not convert Br–(aq) into Br2(l).
Transition metals
L.O.: Deduce the electron configurations of atoms and ions of the d-block elements.
Describe the elements Ti–Cu as transition elements.
Tip: 4s orbital is filled before 3d, but 4s electrons are removed before any electrons are taken out from the 3-d sub-shell.
Write electronic configurations of: Sc, Ti, Cu and Zn.
To which block of the periodic table do Sc, Ti and Cu belong to? Why?
Write the electronic configurations of Sc3+, Zn2+, Cu+ and Cu2+.
Why Sc and Zn are not transition metals?
• 2. Give the electronic configuration of the following ions:
• • a) Co2+
• b) Cu+
• c) V3+
• d) Cr3+
• e) Fe3+
L.O.:
Illustrate the existence of more than one oxidation state for a transition element in its compounds.
Illustrate the formation of coloured metal ions.
Properties of transition metals
List all of the properties metals exhibit :• Good conductors of heat and electricity• High melting and boiling points• Malleable• Ductile• Shinny • Usually strong (high tensile and compressive strength)• Ions are usually brightly coloured• Often can be used when in compounds or as metals as
a catalyst
Catalysis and precipitation
Illustrate the catalytic behaviour of the transition elements and/or their compounds.
Describe the simple precipitation reactions of Cu2+ (aq), Co2+(aq), Fe2+(aq) and Fe3+(aq) with aqueous sodium hydroxide.
Catalytic properties of transition metals
Two main causes for their catalytic properties• They can provide a solid surface onto which
the reactant can ADSORB and thereby hold it in place
• Their variable oxidation state allows them to form intermediates with reactants that lowers the activation energy of the reaction
Catalysts dependent on transition metals
• Catalytic converters – use platinum, rhodium and palladium
• Haber process uses iron• Hydrogenation of alkenes uses nickel metal• Decomposition of hydrogen peroxide uses
MnO2 • CONTACT PROCESS uses vanadium (V) oxide
to convert sulfur dioxide into sulfur trioxide which is needed to make sulfuric acid