How many grams of calcium carbonate are decomposed to produce 11.2 l of carbon dioxide at STP?

First, we need to use the ideal gas law to convert 11.2 L of carbon dioxide at STP to moles:

PV = nRT

(1 atm) (11.2 L) = n (0.0821 L atm/mol K) (273 K)

n = 0.486 mol

Now, we use the balanced chemical equation for the decomposition of calcium carbonate:

CaCO3(s) → CaO(s) + CO2(g)

1 mole of CaCO3 produces 1 mole of CO2. Therefore, the number of moles of CaCO3 decomposed is also 0.486 mol.

Finally, we use the molar mass of CaCO3 to convert mol to g:

0.486 mol CaCO3 x 100.1 g/mol = 48.7 g

Therefore, 48.7 g of calcium carbonate are decomposed to produce 11.2 L of carbon dioxide at STP.