The hydrolysis of the Sn2+ ion in acidic solution has been investigate
d at 25 degrees C and in a 3.000M NaClO4 ionic medium, by measuring th
e concentration of the free protons, h, and of Sn2+, b, with a glass a
nd a 0.5% tin amalgam electrode. The experiments have been performed a
s titrations; during a titration the total metal concentration, B, was
kept constant (0.24mM less than or equal to B less than or equal to 2
.03mM) while the analytical excess of protons, H, was varied (0.4 mM <
H < 4.0mM). Data (h, b, H)(B) have been collected which are most suit
able for evaluations and have the highest precision attainable at pres
ent because the preparation and the analytical manipulation of the tes
t solution has been achieved exclusively by coulometric techniques.