Electricity (resistance)

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Hi, I'm doing a science project on the resistance of distilled water and how it changes when different quantities of salt are added to it. However, when I measured distilled water with a multimeter, the reading kept fluctuating so I couldnt tell whether something was wrong with the multimeter, or the water, or something else entirely. So I just wanted to know what the average resistance of distilled water was so that I could have something to compare my readings to and to isolate the issue I was having.
Thank you!

[norman40]

Hello Dare1100,

Measuring the resistance of water is a little tricky. You really need to keep the multimeter probes at a constant distance apart to get consistent readings. Also, the resistance of distilled water is very high. So you may get better results by measuring the current and then calculating resistance.

There is a similar Science Buddies project that describes a simple sensor and circuit for measuring conductance (resistance is the inverse of conductance) of electrolyte solutions at the following link:

https://www.sciencebuddies.org/science- ... #procedure

My suggestion is to try the procedure shown for your measurements. And let us know if you have any questions about the experiment.

I hope this helps. Please post again if you have more questions.

A. Norman