Question

Calcium carbonate is hygroscopic, meaning it will absorb moisture from the atmosphere. A researcher needs to ensure that the reagent is pure so she places 5.00 g of the calcium carbonate in a 25.0 mL sealed vial and heats this in an oven at 300K for an hour. When heated, solid calcium carbonate can decompose to solid calcium oxide and carbon dioxide gas. If 0.00500% of the solid reagent decomposed, what will the pressure (atm) of carbon dioxide gas in the vial be?

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