A student heats calcium carbonate to produce calcium oxide, according to the following equation: CaCO3 (s) ➔ CaO (s) + CO2 (g)
If the student starts with 100.0 grams of CaCO3 and makes 45.0 g of CaO, what is his percent yield?

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The data below were determined for the reaction shown below. s2o82– + 3i – (aq) → 2so42– + i3– expt. # [s2o82–] (m) [i –] (m) initial rate 1 0.038 0.060 1.4 × 10 – 5 m/s 2 0.076 0.060 2.8 × 10 – 5 m/s 3 0.076 0.030 1.4 × 10 – 5 m/s the rate law for this reaction must be: