No, water is most dense at 4°C. If you take water at 2°C and increase its temperature by a degree, it will _compress_, not expand. But if you take water at 10°C and heat it by a degree it will expand. My question is what percentage of the expansion is offset by the compression.
(Note that the 4°C number is only for pure water.)
> water still weights the same
Weight has nothing to do with my first point. It's the increase in volume that spills into land.
You say it because of the extra volume on top of it?
If that's the case, not because of heating. The volume increases, the water still weights the same.