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The rate water and other elements conduct electricity

2007

I'm a grade 9 student in South Africa doing a Science expo and I need a few facts to help me (using other materials to supply electricity than copper that is usually stolen). Sorry about any spelling and grammar faults, I'm thoroughly afrikaans.

Per cubic centimeter how much electricity does water conduct and the same for iron and copper. Or just compare the conducting rate of average City, river and seawater, iron and copper for me. Could you also give me your name and other references I could use in my reference.

Thank you

Dawie M.
Student - Pretoria, Gauteng, South Africa

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2007

Hi Dawie. Metals like copper conduct electricity in a fundamentally different way than water.

Metals have mobile electrons that easily jump from atom to atom to carry the current through the wire very efficiently. Water has impurities, like low concentrations of salt (NaCl), which separate into positively charged and negatively charged ions like Na⁺ and Cl^-, and can migrate through the water carrying their charge with them.

But there is no comparison in the degree to which these things happen -- ionization of water contaminants happens to only a very small degree. Using water as a substitute for copper for conducting electricity is not practical, as its electrical conductivity is not even a ten-millionth as high. The web page en.wikipedia.org/wiki/Electrical_conductivity gives most of the numbers you are looking for. The conductivity of iron is about 18 percent of copper. The conductivity of aluminum is more than half of the conductivity of copper and it is the most practical substitute for copper in most cases since it is much lighter and not as valuable. Good luck with your project!

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey