Take-Home Assignment #8 Please turn in neatly worked solutions for the following problems by 4:00 PM on Monday, October 22nd. 1. One method for determining the amount of magnesium hydroxide in Milk of Magnesia (MOM) is to dissolve a portion in a solution of HCl. The resulting Mg2+is then precipitated as MgNH4PO4. After filtering, the precipitate is heated, converting it to a final form of Mg2P2O7. The mass of Mg2P2O7in mg, therefore, is the analytical signal. When a 2.00-mL portion of a sample containing 400.0 mg Mg(OH)2per 5.00 mL is treated in this manner, 305.3 mg of Mg2P2O7are obtained. What is the value of kMgfor this analysis? Treat all concentrations in ppm. 2. A potential interferent in this analysis is Zn2+, which will precipitate as ZnNH4PO4and be isolated as Zn2P2O7. In a separate analysis, a 2.00-mL sample containing 400.0 mg Mg(OH)2and 100.0 mg Zn(OH)2per 5.00 mL yields a precipitate of 366.6 mg. What is the value of kZnand the selectivity coefficient, KMg/Zn? Is this method
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