To measure the volume of an irregularly shaped container filled with water,1.00 mL of 2.00 M potassium chloride solution is added.After stirring,a 5.00 mL sample was removed from the container and found to contain 2.54 × 10^-2mg of potassium ion.What is the volume of the container? A)15.4 L B)29.4 L C)2.94 × 10⁴ L D)3.97 × 10^-4 L E)2.54 L

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Quizplus · Accepted Answer

First, calculate the moles of potassium ions in the 5.00 mL sample: $2.54 \times 10^{-2} \, \text{mg} = 2.54 \times 10^{-5} \, \text{g}$. Since the molar mass of potassium (K) is approximately 39.10 g/mol, the moles of K+ in the sample are $2.54 \times 10^{-5} \, \text{g} / 39.10 \, \text{g/mol} = 6.50 \times 10^{-7} \, \text{mol}$. Given that this is from a 5.00 mL sample, the concentration of K+ in the container is $6.50 \times 10^{-7} \, \text{mol} / 5.00 \times 10^{-3} \, \text{L} = 1.30 \times 10^{-4} \, \text{M}$. The original 1.00 mL of 2.00 M KCl solution contains $2.00 \, \text{mol/L} \times 1.00 \times 10^{-3} \, \text{L} = 2.00 \times 10^{-3} \, \text{mol}$ of K+. To find the volume of the container, divide the total moles of K+ by the concentration in the container: $2.00 \times 10^{-3} \, \text{mol} / 1.30 \times 10^{-4} \, \text{M} = 15.4 \, \text{L}$.

To Measure the Volume of an Irregularly Shaped Container Filled