THE TRANSITION ELEMENTS 423Outline how you would determine the concentration of
permanganate ions in the product (practical details are not
required).
(b) Outline the production of (i) chromium, (ii) potassium
dichromate, from chromium(III) oxide, stating the oxidation
states of chromium at the various stages in (ii). Outline how
you would determine the purity of a sample of potassium
dichromate (practical details are not required).
Three crystalline compounds, one violet, one pale green, and
one deep green in colour, all have the molecular formula
CrCl 3 .6H 2 O. When equal masses of the three compounds
are separately treated with an excess of aqueous silver nitrate
at room temperature, the masses of white precipitate produced
are in the ratio 3:2:1. Suggest an explanation for these results.
(C,A)- What do you understand by a complex salt? Give examples,
using a different metal in each case, of complex salts that may be
formed using the following reagents:
(a) ammonia (two examples)
(b) sodium hydroxide (two examples)
(c) potassium cyanide (one example)
(d) potassium iodide (one example)How would you distinguish between the two salts that you have
chosen in each of (a) and (b) and how would you convert the examples
given in (c) and (d) so that the simple metal ion is obtained in each
case? (L, A)
- Write an account of four of the following aspects of transition
metal chemistry :
(a) the factors that determine the electrode potential of the metal;
(b) the preparation of one compound in a high oxidation state;
(c) the change in the M3+/M2+ redox potential as a result of
complex ion formation;
(d) the determination of the formula of any one complex;
(e) the colour of the compounds of the element ;
(f) the electronic structure and physical properties of the element.
(JMB, A)- Find the element V (vanadium) in the given Periodic Table.
(a) Write down the electronic configurations of the species (i) V
and(ii)V^2 +.