Determination of silver in solution with a piezoelectric detector after electrodeposition

Silver in solution is determined in situ by frequency change of a piezoelectric quartz crystal due to electrodeposition on the electrode of the crystal immersed in the solution. A test solution containing EDTA for masking other metal ions flows through a thermostated cell which contains the crystal with platinum-plated electrodes. The frequency change is proportional to the silver concentration in the range 10^?6?3 × 10^?5 M after electrodeposition for 10 min, and 2 × 10^?7?1 × 10^?6 M for 1 h.