# Resistance of water, using AC

Objective

Measure the resistance of ionic solutions, using both DC and AC voltages. We have used normal tap water. Try measuring the resistance using a multimeter first.begin_inset Separator latexparend_inset

Procedure

- R1 should be comparable to R, start with 10k.

- Enable A1 and A2

- Calculate the resistance as explained in section 2.4↑

Discussion

Observed values are shown in the table. The DC and AC resistances seems to be very different. With DC, the resistance of the liquid changes with time, due to electrolysis and bubble formation. The resistance does not depend much on the distance between the electrodes, the area of the electrode is having some effect. The resistance depends on the ion concentration and presence of impurities in the water used.

Try changing the distance between electrodes. Try adding some common salt and repeat the measurements. Why is the behavior different for AC and DC ? What are the charge carriers responsible for the flow of electricity through solutions ? Is there any chemical reaction taking place ?