Scientific laws are statements of facts produced after observed events of nature. There are usually no exceptions to how the outcome of these events unravels. Laws explain HOW nature works.
Explanation:
ON THE OTHER HAND, Theories are usually blanket principles, usually overarching, on how nature has been observed to work. Theories can evolve over time as more information is discovered, but laws are more or less static. Theories explain WHY we see nature to behave in a certain way.
In the case of this question it is scientific law that if a fluid is heated, it becomes less dense as its temperature rises.
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A single electron has a charge of Therefore, if we have an excess of electrons, the total net charge will be the product between the charge of a single electron and the total number of electrons in excess: