Calculate the mass of oxygen obtained by complete decomposition of 10kg of pure potassium chlorate (Atomic mass K=39, O=16 and Cl = 35.5)
`2KClO_3 to 2KCl + 3O_2`

Explanation

Molecular mass of `KClO_3 = 39 + 35.5 + 48 = 122. 5`
Molecular mass of `O_2 = 16 + 16 = 32`
According to the Stoichiometric equation written above ` ( 2 xx 122.5) xx 10^(-3)`kg of `KClO_3` on heating gives `(3 xx 32) xx 10^(-3)` kg of oxygen .
10 kg of `KClO_3` gives =`(3 xx 32 xx 10^(-3))/( 2 xx 122.5 xx 10^(-3)) xx 10`
`=3 .92 kg ` of O_2`