Metal
Ionic radius A°
Hydrated radius A°
Hydration energy (kJmol
-1
)
Solubility of hydroxides (pk
s
)
Hydrolysis
constants (pK
h
)
Electro-negativity
Pb(II)
1.19
4.01
-1481
-
7.80
2.33
Cd(II)
0.97
4.26
-1807
-
11.70
1.69
Ni(II)
0.72
4.04
-2106
14.7
9.40
1.91
Cu(II)
0.69
4.19
-2100
19.6
7.53
2.00
Table 4:
Chemical characteristics of the metal ions.
