119 (atomic mass)- 50 protons= 69 neutrons
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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That it is negatively charged
Answer:
When the charcoal burned, it turned into a gas which caused the mass to change.
Explanation:
You can have as many controls as necessary, But they must remain equal at all times in order to get the most accurate results