If 15.85 grams of magnesium carbonate is heated strongly, wha is the mass of the gas produced?

Answer 1

We begin by finding the chemical formula for Magnesium Carbonate. Since Mg has oxidation number +2 and the charge of CO₃ is -2, the chemical formula is MgCO₃ .

To find the mass of one mole of MgCO_3, check the periodic table for the mass of each element. We have

24+12+ 3(16)=84 g/mole.

Next, write the decomposition equation for MgCO₃. MgCO₃ decomposes to form magnesium oxide and carbon dioxide.

MgCO₃ -----> MgO + CO₂

One mole of magnesium carbonate produces one mole of carbon dioxide.

We start with 15.85 g of MgCO₃

15.85 g x 1 mole/ 84 g = 0.19 moles

Find the molecular weight of CO₂.

12g/mol+2(16)g/mol= 44 g/mol

0.19 moles x 44 g/mole = 8.3 g.

Therefore 8.3 g of carbon dioxide gas is produced.