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Plz help ! Chemisty question ?
If 20.00 g of magnesium react with excess oxygen and 28.00 g of magnesium oxide are produced , what is the percent yield ? 2Mg(s)+O2(g)--->2MgO(s) thank u !
2 Answers
- Randy HamLv 49 years agoFavorite Answer
First we need to calculate our ideal yield.
Atomic mass of Mg = 24.3g/mol
Molecular Mass of MgO = 40.3g/mol
20g / 24.3g/mol = 0.823moles of Mg
From our balanced equation we can see that for every 2 moles of Mg we have we get 2 moles of MgO. Therefore moles of Mg = moles of MgO.
0.823moles * 40.3g/mol = 33.1687 grams of MgO.
Percent yield = (Actual yield / Ideal yield) * 100
(28g / 33.1687g ) * 100 = 84.417%
- ChrisLv 79 years ago
Calculate the number of moles in 20.00 g of Mg
Calculate the number of moles of MgO that would produce
Calculate the number of grams that is
Divide that number into 28.00 and change to a %
