Question

a 3.96 g sample of magnesium carbonate decomposed to produce 1.89 g of magnesium oxide. what mass of nagnesium was in the sample of magnesium carbonate? calculate the percent of magnesium by mass , in the magnesium oxide produced. how much co2 was released into the atmosphere.

Answer 1

(3.96 g MgCO3) / (84.31413 g MgCO3/mol) x (1 mol Mg / 1 mol MgCO3) x  

(24.30506 g Mg/mol) = 1.14 g Mg 

w(Mg)=(24.30506 g/mol) / (40.30449 g/mol) = 0.603036 = 60.3036% Mg 

MgCO3 → MgO + CO2 

m(CO₂)=(3.96 g MgCO3) - (1.89 g MgO) = 2.07 g CO2