20.0 g of a magnesium carbonate sample decomposes on heating to give carbon dioxide and8.0 g magnesium oxide. What will be the percentage of purity of magnesium carbonate in the sample?

20.0 g of a magnesium carbonate sample decomposes on heating to give c

1.	20.0 g of a magnesium carbonate sample decomposes on heating to give carbon dioxide and8.0 g magnesium oxide. What will be the percentage of purity of magnesium carbonate in the sample?
Answer» 60 84 75 96 Solution :`MgCO_(3) overset(Delta)(to) MgO + CO_(2)UARR` 84 g of `MgCO_(3)`gives 40 g of MgO. (100% purity) 20g of `MgCO_(3)` will give `=(40xx20)/84=9.52g` 9.52g of MgO is given by 100% pure `MgCO_(3)`. 8.0 g of MgO will be given by=`(100xx8)/9.52=84.03%`