Chem I Help Please?

Question

Solid potassium chlorate (KClO3) decomposes into potassium chloride and oxygen gas when heated. How many moles of oxygen form when 46.1 g completely decomposes?

What mass of carbon dioxide is produced from the complete combustion of 8.50×10−3 g of methane?

Answer 1

2KClO₃(s) ==> 2KCl(s) + 3O₂(g) ... balanced equation for decomposition of KClO₃(s)

molar mass KClO3 = 122.5 g/mol

46.1 g KClO₃ x 1 mol / 122.5 g x 3 mols O₂ / 2 mols KClO₃ = 0.564 moles of O₂ produced

Combustion of methane (CH4):

CH₄ + 2O₂ ==> CO₂ + 2H₂O ... balanced equation

molar mass CH4 = 16 g/mol

8.50x10^-3 g CH₄ x 1 mol / 16 g x 1 mol CO₂ / mol CH₄ x 44 g CO₂/ mol = 0.0234 g CO₂