When carbon is burned in air, it reacts with oxygen to form carbon dioxide. When 13.2 g of carbon were burned in the presence of 48.8 g of oxygen, 13.6 g of oxygen remained unreacted. What mass of carbon dioxide was produced?

Question

Express your answer to one decimal place and include the appropriate units.

Answer 1

C(s) + O2(g) ==> CO2(g)
mols C = grams/atomic mass = 13.2/12 = 1.1 initially.
48.8 g O2 initially - 13.6 g O2 remaining = 35.2 g O2 used.
mols O2 used = g/molar mass = 35.2/32 = 1.1
The equation tells you that 1.1 mols C will use 1.1 mols O2 to produce 1.1 mols CO2.
g CO2 = mols CO2 x molar mass CO2 = 1.1 x 44 = ? grams CO2.