A laboratory unknown is a mixture of calcium carbonate and magnesium carbonate. These substances decompose to form calcium oxide and magnesium oxide, respectively, when heated at a high temperature for a prolonged period. A sample of this laboratory unknown mixture with a mass of 5.424 grams was decomposed by heating for several hours at 950 ^°C. The oxide residue produced had a mass of 2.791 grams. From this laboratory data calculate the percent, by weight, of calcium carbonate in the unknown. Hint: Use the balanced chemical equations to find the molar ratios of the carbonates to the oxides, then create two algebraic equations - one for the carbonates and the other for the products. This will give you two equations with two unknowns, which can be solved to determine the number of moles of one of your substances.

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The Answer of A laboratory unknown is a mixture of calcium carbonate and magnesium carbonate. These substances decompose to form calcium oxide and magnesium oxide, respectively, when heated at a high temperature for a prolonged period. A sample of this laboratory unknown mixture with a mass of 5.424 grams was decomposed by heating for several hours at 950 ^°C. The oxide residue produced had a mass of 2.791 grams. From this laboratory data calculate the percent, by weight, of calcium carbonate in the unknown. Hint: Use the balanced chemical equations to find the molar ratios of the carbonates to the oxides, then create two algebraic equations - one for the carbonates and the other for the products. This will give you two equations with two unknowns, which can be solved to determine the number of moles of one of your substances.

A Laboratory Unknown Is a Mixture of Calcium Carbonate and Magnesium