Answer:

Explanation:
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In this case, according to the given chemical reaction, it is possible for us to realize that the 46.2 kJ of energy are given per mole of reaction, which are related to 3 moles of hydrogen; Thus, we can calculate the energy per mole of hydrogen as shown below:

Now, to calculate the total energy, we convert the grams to moles of hydrogen as shown below:

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It changes because when the 2 tectonic plates collide they form mountains and volcanoes.
Continental drift causes tectonic plates to either "pull apart" or "crash" into each other.
Plates that crash into each other either form mountains, or when one slides under the other (a subduction zone) volcanoes from.
Answer: An element os made up of one kind of atom.
Explanation: Dalton's concept states that all atoms of an element is identical.