Transition metals

• reactions of Co2+

  A) pink solution

  B) blue precipitate

  C) pale brown precipitate

  D) purple precipitate

  E) blue solution

  
• $ΔE=$$hv$

  E= energy absorbed by electron from ground state to excited state

  h= planks constant
• complex 


  atom or ion or transition metal bonded to 1 or more ligands by a coordinate bond
• • Heterogeneous means in a different phase/state from reactants
  • Catalyst speeds up reaction and is left unchanged and lowers the activation energy for the reaction
  • Hydrogen and nitrogen adsorb onto the surface
  • Bonds weaken
  • Products desorb / leave from the surface of the iron
  • Large surface area of iron by using powder or small pellets or support medium/mesh
  • Catalyst poisoned
  • so Active sites blocked

  
• Slow

  • both reactants negative ions so repel
  • this causes the activation energy to be high

  
• Explain why the replacement of water ligands by ethanedioate ions is favourable 


  change in enthalpy in negligible (close to 0)

  • make and break the same number of bonds
  • make and breaks the same type of bonds (bonds have similar enthalpies)
  • 6 Fe- O bonds broken, 6 Fe - O bonds made

  Causes an increase in entropy

  • increase in particles in soloution (4 to 7)

  Causes $ΔG° =$$ΔH° - TΔS°$

  • $ΔG°$to be negative
  • S will be positive -TS will always be negative at all temperatures
  • so G will always be negative making it more favourable

  
• • Cis/trans


  Cis Trans

  
• Explain why the solution containing [Al(H20)6]** is acidic.

  Al3+ has a high charge density

  al3+ weakens the o-h bond in water ligands ands donates H+ to water (h3o+)