The filter paper salt bridge is not wetted with the 0.1 M KNO3 solution. As a result, will be measured potential of the cell be too high, too low, or unaffected? Explain.
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too low,
As electrons leave one half of a galvanic cell and flow to the other, a difference in charge is established. If the filter paper salt bridge is not wetted, this charge difference would prevent further flow of electrons. A salt bridge allows the flow of ions to maintain a balance in charge between the oxidation and reduction vessels while keeping the contents of each separate. With the charge difference balanced, electrons can flow once again, and the reduction and oxidation reactions can proceed. In general, keeping the two cells separate is preferable from the point of view of eliminating variables from an experiment. When no direct contact between electrolytes is allowed, there is no need to make allowance for possible interactions between ionic species.
As electrons leave one half of a galvanic cell and flow to the other, a difference in charge is established. If the filter paper salt bridge is not wetted, this charge difference would prevent further flow of electrons. A salt bridge allows the flow of ions to maintain a balance in charge between the oxidation and reduction vessels while keeping the contents of each separate. With the charge difference balanced, electrons can flow once again, and the reduction and oxidation reactions can proceed. In general, keeping the two cells separate is preferable from the point of view of eliminating variables from an experiment. When no direct contact between electrolytes is allowed, there is no need to make allowance for possible interactions between ionic species.