The first term is associated with zero point energy and does not contribute to specific heat.
In particular, it depends on the specific heat and the mass of the contents.
Thus, adding salt to water can only reduce its specific heat.
Water has a higher specific heat than a salt solution.
Using the specific heat of the products that are present than you can get good figures.
In the case of ice, you were still measuring this same specific heat.
Assume there are two systems with the same mass and specific heat.
In the most general case, the specific heat is a function of both temperature and pressure.
The sea is warmed by the sun more slowly because of water's greater specific heat compared to land.
By contrast, the land, with a lower specific heat, can vary several degrees in a matter of hours.
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