The Amount of Calcium Present in Milk Can Be Determined

question 104

Multiple Choice

The amount of calcium present in milk can be determined by adding oxalate to a sample and measuring the mass of calcium oxalate precipitated. What is the mass percent of calcium if 0.429 g of calcium oxalate forms in a 125-g sample of milk when excess aqueous sodium oxalate is added? Na₂C₂O₄(aq) + Ca²⁺(aq)  CaC₂O₄(s) + 2Na⁺(aq)

• A) 0.107%
• B) 0.202%
• C) 0.343%
• D) 1.10%
• E) 1.37%

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