How many moles of cl- ions are needed to completely combine with 0.25 moles of mg+2 ions

The amount of Cl- ion moles needed to combine with 0.25 moles of Mg+2 ions is 0.50. The problem gives us how much Mg we're working with, 2. This means, we also need to use x's two of Cl to completely get a reaction.

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