Answer:
4- radioactive isotopes
Explanation:
I don't remember exactly but this question was on the regents
The formula will be AI2O3
Answer:

Explanation:
There are two heat transfers involved: the heat lost by the metal block and the heat gained by the water.
According to the Law of Conservation of Energy, energy can neither be destroyed nor created, so the sum of these terms must be zero.
Let the metal be Component 1 and the water be Component 2.
Data:
For the metal:

For the water:




Answer:
1: At temperatures below 542.55 K
2: At temperatures above 660 K
Explanation:
Hello there!
In this case, according to the thermodynamic definition of the Gibbs free energy, it is possible to write the following expression:

Whereas ΔG=0 for the spontaneous transition. In such a way, we proceed as follows:
1:

It means that at temperatures lower than 542.55 K the reaction will be spontaneous.
2:

It means that at temperatures higher than 660 K the reaction will be spontaneous.
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