In the context of multivalent ions, it is when it has multiple oxidative states.
The answer is number 1 - energy is emitted
Energy is released when an atom in an excited state returns to the ground state.
Answer:

Explanation:
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In this case, since the molarity of a solution is calculated by diving the moles of solute by the volume of solution in liters, we first compute the moles of barium hydroxide in 35.5 g as shown below:

Then, the liters of solution:

Finally, the molarity turns out:

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