Abstract:
The sudy of precondition time in ion selective electrode (ISE) of methanil yellow has been done. The first step in this research was optimized of membrane composition by measure potensial value of chitosan, PVC and DOP membrane and calculate the Nernst factor. The membrane with Nernst factor nearly the Nernst factor teory 59,2 mV/decade was used to determine precondition time. Precondition time process was measured potensial value of ISE membrane in methanil yellow 1.10-1 – 1.10-8 M with variation time were 10, 20, 30, 40, 50, 60, 70, 80 minutes and calculated the Nernst factor. The results of this research showed that membrane composition optimum was 20% chitosan : 30% PVC : 50% DOP with Nernst factor 56,82 mV/decade concentration.The precondition time optimum at 50 minutes with Nernst factor 64,29 mV/decade concentration and R2 = 0.9992.