I'm doing an experiment where I'm measuring the effect of changing the $\ce{Cu^{2+}}$ ion concentration on the voltage in a copper-zinc galvanic cell.
I'll be doing at least five trials for each of the five concentrations I'm testing for (from $0.2-1.0\:\mathrm{M}$), so in total that is 25 trials. However, do I need a new piece of filter paper as a salt bridge for each trial, or can I reuse the same piece of filter paper and dip it in a $\ce{KCl}$ solution each time? Do I really need to make 25 separate pieces of filter paper?