What does Principal QN tell you? What are the numbers that Principal QN can be? (QN stands for quantum number)

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How many moles of magnesium is 3.01 x10^22 atoms of magnesium?

For each of the following compounds, decide whether the compound's solubility in aqueous solution changes with ph. if the solubility does change, pick the ph at which you'd expect the highest solubility. you'll find ksp data in the aleks data tab. compounds does solubility change with ph