5. What is the molarity of a solution if 3.79 g of cobalt (II) nitrate hexahydrate is dissolved in water to make 100.0 mL of solution?

6. If 55.0 mL of 3.00 M nitric acid is added to 250.0 mL of water, what is the molar concentration of nitric acid in the resulting solution?

7. Perchloric acid can be neutralized in an acid-base reaction by magnesium hydroxide, producing magnesium hydroxide, producing magnesium perchlorate and water. How many grams of magnesium hydroxide are required to completely neutralize 328.0 mL of 1.27 M perchloric acid?

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