Part A) When heated, calcium carbonate decomposes to yield calcium oxide and car
ID: 950382 • Letter: P
Question
Part A)
When heated, calcium carbonate decomposes to yield calcium oxide and carbon dioxide gas via the reaction
CaCO3(s)CaO(s)+CO2(g)
What is the mass of calcium carbonate needed to produce 33.0 L of carbon dioxide at STP?
Express your answer with the appropriate units.
part B)Butane, C4H10, is a component of natural gas that is used as fuel for cigarette lighters. The balanced equation of the complete combustion of butane is 2C4H10(g)+13O2(g)8CO2(g)+10H2O(l) At 1.00 atm and 23 C, what is the volume of carbon dioxide formed by the combustion of 1.40 g of butane? Express your answer with the appropriate units
Explanation / Answer
part A
At STP, 1 mol of gas has a volume of 22.4 L. So,
33.0 L / 22.4 L/mol = 1.47 moles CO2 X (1 mol CaCO3/1 mol CO2)
= 1.47 mol CaCO3 X 100.1 g/mol
= 147 g CaCO3
For the second problem:
1. Molecular Weight of Butane=58
2. 1.20 g/58 =0.020 moles of butane
3. Use the conversion (8 mol CO2 / 2 mol butane)
=4x0.020=0.081moles of CO2
4. Use ideal gas law to calculate volume of CO2 (PV=nRT)
1xV=0.08x8.314x296
V=196m3