It's all in the title. I'm looking for a mathematical relationship.
what sort of relationship and under what circumstances? As stated there's not enuf to help you.
I think you are looking for the formula for thermal expansion.
change in volume=(coefficient of volume expansion)(initial volume)(change in temperature)
ok that makes sense, the density of H2O vs T: http://www.simetric.co.uk/si_water.htm
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