CeCl3 is having Ca conntent 12 g/L,If we try to pricipitate Ce2(CO3)by using 1.0M Na2CO3,what is the Ca impurity level in the fianl Ce carbonte and how much pH we have to maintain to control Ca imprurity in the final out put?
To determine the Ca impurity level in the final Ce carbonate and the pH required to control the Ca impurity, we need to understand a few concepts and perform some calculations. Let's break it down step-by-step:
1. Calculate the number of moles of CeCl3:
Since we know the concentration of CeCl3 is 12 g/L, we need to convert it to moles. The molar mass of CeCl3 is 246.48 g/mol.
Number of moles of CeCl3 = (12 g/L) / (246.48 g/mol)
2. Calculate the amount of Ce2(CO3) precipitated:
Ce2(CO3) is formed by the reaction between CeCl3 and Na2CO3. The balanced chemical equation is:
2 CeCl3 + 3 Na2CO3 → Ce2(CO3)3 + 6 NaCl
The stoichiometry of the reaction shows that 2 moles of CeCl3 react with 3 moles of Na2CO3 to form 1 mole of Ce2(CO3)3.
3. Calculate the amount of Ca impurity:
Since only Ce2(CO3)3 precipitates, we assume that all the CeCl3 will convert to Ce2(CO3)3. Therefore, the amount of Ca impurity in the final Ce carbonate is equivalent to the amount of Ca impurity in the initial CeCl3 solution.
4. Determine the pH required to control Ca impurity:
To prevent the precipitation of CaCO3 during the precipitation of Ce2(CO3)3, we need to maintain the pH above the pKa of CaCO3, which is approximately 9.0.
By maintaining the pH above 9.0, the Ca impurities will remain in solution as Ca2+ ions and will not precipitate with Ce2(CO3)3.
Note: The exact pH required to control the Ca impurity may vary depending on the specific conditions of the reaction and the solubility of Ce2(CO3)3 with Ca impurities.
It's important to note that these calculations assume ideal conditions and may not account for other factors that could affect the reaction. Always consult experimental data and consider practical constraints when performing chemical reactions.