Five grams of `KCIO_(3)` yield `3.041 g` of `KCI` and `1.36 L` of oxygen at standard temperature and pressure. Show that these figures support the law of conservation of mass within limits of `+- 0.4 %` error.

Explanation

Mass of 22.4 L of oxyegn at S.T.P. = 32 g (gram molar mass)
Mass of 1.36 of oxygen at S.T.P `= (("1.36 L"))/(("22.4 L"))xx(32g)=1.943g`
The chemical equation involved in the reaction is :
`2KClO_(3)(s)rarr2KCl(s)+3O_(2)(g)`
Mass of the reactant = 5.0 g (given)
Mass of the reactant `= (3.041 + 1.943)=4.984 g`
Error involved `= (5.0 - 4.984)=0.016 g`
`:.` Percent error involved `= ((0.016g))/((5g))xx100=0.32`
As the error is within the limits of `pm 0.4 %`, the law of conservation of mass is supported.