Chemistry of TM Flashcards
What are the common oxidation states of Ti?
+4
What are the common oxidation states of V?
+3, +4, +5
What are the common oxidation states of Cr?
+2, +3, +6
What are the common oxidation states of Mn?
+2, +4, +7
What are the common oxidation states of Co?
+2, +3
What are the common oxidation states of Ni?
+2
What are the common oxidation states of Cu?
+1, +2
What is the common oxide of Titanium? Formation equation?
TiO₂
Ti⁴⁺ + O²⁻ -> TiO₂
How do you get the pure titanium metal from the oxide?
Use the Kroll process then reduce
What is the equation for the Kroll process for extracting pure titanium?
TiO₂ + 2C + 2Cl₂ -> TiCl₄ + 2CO
What must you do once you have the TiCl₄?
Reduce it so the Ti4+ then becomes Ti
What is the equation for reducing TiCl₄?
2Mg + TiCl₄ -> Ti + 2MgCl₂
What does the Ellingham diagram tell you?
What reaction is used to drive the process
Tells you the thermodynamics of the reaction
How would you know which reaction to choose from an Ellingham diagram?
Easiest to look at the thermodynamically more favourable to drive the reaction.
Reaction below the reaction you need
What do you use to reduce vanadate?
Zn -> Zn2+ + 2e-
What colour is the VO2+ ion? Oxidation state of V?
Blue
+4
What colour is the V3+ ion? Oxidation state?
Green
3+
What colour is the [V(H2O)6]2+ complex? Oxidation state of V?
Lavender
2+
What is the oxidation state of chromate?
6+
Where does chromate (yellow) only exist?
Solution under alkaline conditions because of equilibrium
What equation shows that chromate solutions are basic?
CrO₄²⁻ + H₂O -> HCrO₄⁻ + HO⁻
What colour is chromate?
Yellow
What colour is dichromate?
Orange-red
Why are chromate compounds coloured?
Due to charge transfer
An electron from a filled pi orbital is transferred into the empty d orbital
Ligand to metal charge transfer
What is an application of chromate compounds?
Breathalyser test