Final answer:
The molar concentration of Ca₂⁺ in the solution is calculated by first determining the moles of CaCO₃ precipitate formed and then calculating the moles of Ca₂⁺ present in the original volume of the solution. The result is a molar concentration of 2.997 M for Ca₂⁺.
Step-by-step explanation:
To calculate the molar concentration of Ca₂⁺ in the solution, we start by recognizing that the precipitate formed, CaCO₃, has a mass of 3.00g. The molar mass of CaCO₃ (calcium carbonate) is approximately 100.09 g/mol. Using dimensional analysis, we can convert this mass to moles of CaCO₃:
3.00 g CaCO₃ × (1 mol CaCO₃ / 100.09 g CaCO₃) = 0.02997 mol CaCO₃
Since calcium carbonate and calcium ion (Ca₂⁺) are in a 1:1 molar ratio, the moles of Ca₂⁺ in the original solution is also 0.02997 mol. To find the concentration of Ca₂⁺, we divide the moles by the volume of the solution in liters:
0.02997 mol Ca₂⁺ / 0.010 L = 2.997 M
The molar concentration of Ca₂⁺ in the 10.0 mL solution is 2.997 M.