transition metals

• what is a transition metal?

  an element that produces stable ions with partly filled d-orbital
• what is a d-block element?

  an element with its outer electrons highest energy level in in the d-sub shell
• what two elements are not transition metals?

  scandium and zinc
• whats similiar about 4s orbitals and 3d orbitals?

  they are really close in energy
• whats the electron configuration of chromium?

  [Ar] 3d5 4s1
• whats the electron configuration of copper?

  [Ar]4s1 3d10
• why is chromiums 3d shell half full and coppers 3d shell full?

  so its more stable
• name the 4 chemical properties of transition metals?

  1. catalyst
  2. form coloured ions
  3. variable oxidation states
  4. complex formation
• what is a complex?

  when a central metal atom or ion is surrounded by ligands
• define ligand

  atom , ion or molecule that will donate a pair of electrons to a central metal
• what is a monodentate ligand?

  donates only one lone pair of electrons
• what is a bidentate ligand?

  donates 2 lone pairs of electrons
• whats an example of a bidentate ligand?

  ethandioate and ethane-1,2-diamine
• draw an ethanedioate molecule

  [C2O4]2-

  
• draw ethane-1,2-diamine

  H2NCH2H2NH2

  
• whats an example of a multidentate ligand?

  EDTA4- (chelate)
• whats the chelate effect?

  can form many co-ordinate bonds
• how many coordinate bonds can EDTA form?

  6
• what is haem?

  an iron(II) complex with a multidentate ligand
• how does oxygen get transported?

  oxygen forms a coordinate bond to Fe(II) in haemoglobin,
• how is CO (carbon monoxide) toxic?

  CO can form a strong dative bond with haemoglobin

  this bond is stronger than that made with oxygen so it replaces the oxygen
• how does colour arise?

  when wavelengths of visible light are absorbed and some of the remaining wavelengths of light are transmitted or reflected
• what happens to d electrons when light is absorbed

  move from ground state to excited state
• what colours are all the vanadium ions in their 4 main oxidation states?

  colours

  
• what colour is [Cr2O7]2-

  orange
• what colour is Mn2+

  pink
• what colour is MnO4 -

  purple
• what colour is Fe2+

  green
• what colour is Fe3+

  yellow
• what colour is Ni2+

  green
• what colour is Cu2+

  blue
• what colour is Cr3+

  green/violet

  its violet when its surrounded by 6 H2O but its normally substituted so it look green
• what shape are complexes with a coordination number of 6

  octahedral (90')
• what shapes are complexes with 4 coordination numbers?

  tetrahedral and square planar
• example of a square planar complex

  cis-platin
• bond angle of a tetrahedral

  109.5
• bond angle of a square planar molecule

  90'
• draw cis-platin


  cis platin

  
• what is cis-platin

  anti cancer drug
• whats an example of a linear complex

  usually silver complexes like ( tollens reagent)