# Q & A: Thermal Conductivities

Q:
Is there a chart of how different metals conduct heat? I have found one for electrical conductivity. Do the metals which conduct electrical energy best also conduct heat in the same way? If there is not a chart, could you tell me which metals conduct better than others and why?
- Sean (age 12)
Irving School, Oak Park, IL USA
A:
Sean -

You guessed it. The main way metals conduct heat is via the same moving electrons that conduct electricity. So it's nearly true for ordinary metals that the thermal conductivity is just proportional to the electrical conductivity. (This is called the Wiedemann-Franz law.) So you can use your conductivity chart with confidence.

If you want actual numbers of the "thermal conductivity" for different materials. You can find tables like this in any of the good handbooks for physical properties (for example, the CRC Handbook or the Merck Index). Your school library will probably have a book like this.

You can also find some tables like online, but they may not give you all the information you need. How easily something will conduct heat actually depends on the temperature of the object, as well as what the object is made of. But many tables just list it at one temperature. The books that I mentioned before give the conductivities at lots of different temperatures, not just one.

You can also find most any information you're looking for by looking at a detailed periodic table like the one at
. This site has all sorts of information (including thermal conductivities) for all the different elements.

And finally, for why different things conduct heat the way they do, you can check out the answer our to the question
.

-Tamara & Mike

(published on 10/22/2007)