Question

1. when 78.2 g of potassium react with magnesium chloride, the products are 24.3 g of magnesium and 149.2 g of potassium chloride. how much magnesium chloride was used?

Explanation:

Step1: Apply the law of conservation of mass

The law of conservation of mass states that in a chemical reaction, the mass of reactants is equal to the mass of products. Let the mass of magnesium chloride be \(x\). The reactants are potassium (\(78.2\space g\)) and magnesium chloride (\(x\)). The products are magnesium (\(24.3\space g\)) and potassium chloride (\(149.2\space g\)). So, we can set up the equation \(78.2 + x=24.3 + 149.2\).

Step2: Solve the equation for \(x\)

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Answer:

\(95.3\space g\)