A pH meter (Figure 16.6) employs a voltaic cell for which the cell potential is very sensitive to pH. A simple (but impractical) pH meter can be constructed by using two hydrogen electrodes: one standard hydrogen electrode (Figure 20.10) and a hydrogen electrode (with 1 atm pressure of H2 gas) dipped into the solution of unknown pH. The two half-cells are connected by a salt bridge or porous glass disk. (a) Sketch the cell described above. (b) Write the half-cell reactions for the cell, and calculate the standard emf. (c) What is the pH of the solution in the half-cell that has the standard hydrogen electrode? (d) What is the cell emf when the pH of the unknown solution is 5.0? (e) How precise would a voltmeter have to be in order to detect a change in the pH of 0.01 pH units?
We need at least 10 more requests to produce the solution.
0 / 10 have requested this problem solution
The more requests, the faster the answer.