Use.
PV = nRT
To get moles O2. ( 20.0o C = 293.15 Kelvin )
(1.00 atm)(1120.0 L) = (X moles)(0.08206 L*atm/mol*K)(293.15 K)
Moles = 1120.0/24.56
= 45.60 moles O2
-----------------------------------now,
45.60 moles O2 (1 mole KO2/2 mole O2)(71.1 grams/1 mole KO2)
= 1621 grams potassium oxide required
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