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:




20 mol of NH, can be produce from 30 mol o H2
B! because the hydrogen causes some nuclear reactions.
Answer:
Physical Change
Explanation:
A solid being crushed into a powder is a physical change because a chemical change is when substances combine to create new substances.
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