Which side of the 0.5 M NaBr | 0.5 M KBr junction will be more negative?explain
To determine which side of the 0.5 M NaBr | 0.5 M KBr junction will be more negative, you need to consider the relative electrochemical potentials or reduction potentials of the ions involved.
Step 1: Determine the half-cell reactions:
For the NaBr solution:
Na+ + e- → Na(s)
For the KBr solution:
K+ + e- → K(s)
Step 2: Find the standard reduction potentials of Na+ and K+:
The standard reduction potentials can be found in standard reduction potential tables. The more positive the value, the stronger the oxidizing agent (it accepts electrons more readily), and the more negative the value, the stronger the reducing agent (it donates electrons more readily).
From the standard reduction tables, the reduction potentials for Na+ and K+ are as follows:
Na+ + e- → Na(s) : -2.71 V
K+ + e- → K(s) : -2.93 V
Step 3: Compare the reduction potentials:
Since both reduction potentials are negative, the more negative value indicates the stronger reducing agent. In this case, K+ (-2.93 V) has a more negative reduction potential compared to Na+ (-2.71 V).
Step 4: Determine which side is more negative:
Since K+ has a more negative reduction potential, the side with the KBr solution will be more negative in the 0.5 M NaBr | 0.5 M KBr junction.
In summary, the KBr solution will be more negative because the reduction potential of K+ is more negative than that of Na+.