To determine the concentration of copper ions in a wastewater sample from a factory using polarography, follow these steps:1. Sample collection and preparation: Collect a representative wastewater sample from the factory. Filter the sample to remove any suspended particles and debris. If necessary, dilute the sample to bring the concentration of copper ions within the working range of the polarographic instrument.2. Calibration: Prepare a series of standard solutions containing known concentrations of copper ions. These standards will be used to create a calibration curve, which will help in determining the concentration of copper ions in the wastewater sample.3. Polarographic analysis: Set up the polarographic instrument, which typically consists of a dropping mercury electrode DME as the working electrode, a reference electrode such as a saturated calomel electrode , and an auxiliary electrode. Connect the electrodes to a potentiostat and a recorder.4. Record the polarograms: First, record the polarograms for the standard solutions. Adjust the potential of the working electrode in a stepwise manner, and measure the resulting current. The current will increase as the potential reaches the reduction potential of copper ions, and a peak will be observed. The height of the peak is proportional to the concentration of copper ions in the solution.5. Create a calibration curve: Plot the peak heights of the polarograms obtained from the standard solutions against their respective copper ion concentrations. Fit a linear regression line to the data points to create a calibration curve.6. Analyze the wastewater sample: Record the polarogram for the wastewater sample following the same procedure as for the standard solutions. Determine the peak height corresponding to the reduction of copper ions.7. Determine the concentration of copper ions: Use the calibration curve to find the concentration of copper ions in the wastewater sample based on the measured peak height. If the sample was diluted in step 1, remember to account for the dilution factor when calculating the final concentration of copper ions in the original wastewater sample.8. Report the results: Report the concentration of copper ions in the wastewater sample, along with any relevant information about the sample collection, preparation, and analysis.