Two samples of calcium fluoride are decomposed into their constituent elements. the first sample produced 0.154 g of calcium and 0.146 g of fluorine. if the second sample produced 294 mg of fluorine, how many g of calcium were formed? 0.309 g 3.09 × 102 g 3.13 g 0.280 g 2.80 × 102 g

When a compound is decomposed into constituent elements, the amount of elements produced will remain in the same proportion every time it is decomposed. When the second sample of calcium fluoride is decomposed, the proportion of calcium and fluorine should remain same as first time. Hence, calcium produced = 294 * 0.154/0.146 = 309 mg or 0.309 g

The mass has escaped into a gas which you can not see so the law stays true.