Experiment 1: Salt Water Capacitor Concentration (cont.)

We continued the capacitor experiment now that the four solutions and bottles were prepared. The testing procedure was especially easy, but had surprising results.

Note: links are pictures

Procedure:

1. Placing one probe on the conductive screw and one on the exterior foil, use the multimeter to measure the capacitance of the four different concentrations.

2. Use two new concentrations of salt water to refine data, placing their concentration near the highest capacitance solution's concentration.

Results:

Table 1.1: Salt-to-water ratio and capacitance

Bottle	Ratio of Salt to Water	Capacitance (nF) ± 1 nF
1	26.9 g / 300 mL	2
2	53.9 g / 300 mL	1
3	80.8 g / 300 mL	1
4	107.7 g / 300 mL	1
5	20.0 g / 300 mL	1
6	10.0 g / 300 mL	1

Analysis:

According to the data gathered, the 26.9 g / 300 mL had the highest capacitance. This was contrary to our hypothesis, and we plan to delve further into the theory as to why this is true. Current ideas suggest that the lower salt-water concentration allows the ionized particles to move with more freedom. We are searching for a more definite answer.

We want to have a more definite and precise method to measure the capacitance of these capacitors. The multimeter gave the measurement to the nearest nF, without a decimal point. This made determining the pattern of concentration to capacitance difficult, since we only have two levels (1 and 2 nF) of capacitance. I will search for a more accurate tool.

Using this result, the group began the next phase of our capacitor experiments.