Question

What mass of solid NaOH (97.0% NaOH by mass) is required to prepare 1.00 l of a 10.0% solution of NaOH by mass? The density of the 10.0% solution is 1.109 g/ml.

Answer 1

To prepare 1.00 L of a 10.0% NaOH solution when using 97.0% pure solid NaOH, one would require 114.3 g of the solid NaOH, considering the density of the final solution to be 1.109 g/mL.

Step-by-step explanation:

The question is asking what mass of solid NaOH is required to prepare 1.00 liter of a 10.0% NaOH solution by mass, knowing that the solid NaOH is 97.0% pure and the density of the 10.0% solution is 1.109 g/mL. To determine the mass of solid NaOH, we will need to calculate the mass of the NaOH in the final solution and then account for the purity of the solid NaOH.

First, calculate the total mass of the 10.0% solution:

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Then, calculate the mass of NaOH in the solution:

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Finally, adjust for the purity of the solid NaOH:

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This calculation assumes that the mass of the NaOH in the final solution is the same as the solid needed initially, adjusted for the purity of the reagent. By performing these calculations, we determine the mass of the solid reagent needed to make a specific concentration of solution.