A voltaic cell designed to measure [Cu2+]is constructed of a standard hydrogen electrode and a copper metal electrode in the Cu2+ solution of interest.

1. If you wanted to construct a calibration curve for how the cell potential varies with the concentration of copper(II), what would you plot in order to obtain a straight line?
Answer: log[Cu2+]versus E0cell.

2. What would be the slope of the line? Express your answer using two significant figures.

Answer: ? V

To construct a calibration curve for the cell potential varying with the concentration of copper(II), you would need to plot log[Cu2+] versus E0cell, where log[Cu2+] is the logarithm of the copper(II) concentration and E0cell is the standard cell potential.

To obtain a straight line on the plot, you need to understand the relationship between the concentration of copper(II) and the cell potential. In this case, the concentration of copper(II) will have an effect on the cell potential, which can be expressed mathematically as:

E = E0 + (0.0592/n) * log[Cu2+]

where E is the cell potential, E0 is the standard cell potential, n is the number of electrons involved in the redox reaction, and [Cu2+] is the concentration of copper(II).

From this equation, we can see that the cell potential is directly related to the logarithm of the copper(II) concentration. Plotting log[Cu2+] on the x-axis and E0cell on the y-axis will create a straight line.

Now, let's move on to the second question. The slope of the line represents the change in the cell potential for each unit change in log[Cu2+]. To calculate the slope, we can use two points on the calibration curve and apply the formula:

Slope = (E2 - E1) / (log[Cu2+]2 - log[Cu2+]1)

Given that the significant figure requirement is two, we need to round the slope to two significant figures.

Note: Unfortunately, I cannot provide the exact slope for the given data since the specific points on the calibration curve are not provided. You would need to perform the experiment and collect the necessary data points to determine the slope accurately.