what volume of oxygen gas measures at s.t.p will be produced from the decomposition of 2.50g of potasium trioxochlorate (v) (K =39,Cl =35.5, O =16 molar volume of a gas at s.t.p =22.4dm-3

Answer 1

Note that your name for KClO3 is not approved by IUPAC.
2KClO3 ==> 2KCl + 3O2
mols KClO3 = grams/molar mass = 2.50/122.5 = ?
mols O2 = mols KClO3 x (3/2) = ? Then are 22.4 L/mole O2 produced at STP.
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