[Ime]

I would appreciate help with an experiment. I was mixing K2PtCl4 with  NaCl and DNA in water. pH changes from 6 to 3.5 in a week and it is not clear to me what would cause such a slow change since K2PtCl4 should easily dissociate into K2 and PtCl4. Can you please suggest possible reason for this slow decrease in pH.

Thanks.

[FeLiXe]

seems like HCl forms when your PtCl4^{2- decays}