Question

Consider the following reaction:
`KClO_(3)(s)overset(Delta)toKCl(s)+O_(2)(g)`, yield`=60%`
`Zn(s)+H_(2)SO_(4)(aq)toZnSO_(4)(aq)+H_(2)(g)`, yield `=50%`
`2H_(2)(g)+O_(2)(g)to2H_(2)O(l)`, yield`=50%`
What volume of 0.2 M `H_(2)SO_(4)` solution is required to produce enough `H_(2)` to completely react with `O_(2)` liberated due decomposition of `1.225 g KClO_(3)`.
(Molecular weight of `KClO_(3)=39+53.5+3xx16`
`=122.5g mol^(-1)`)
A. 150 mL
B. 180 mL
C. 360 mL
D. 480 mL

Answer 1

Correct Answer - B

(i). `KClO_(3)(s)overset(Delta)toKCl(s)+(3)/(2)O_(2)(g)`
(ii). `H_(2)(g)+(1)/(2)O_(2)(g)toH_(2)O(l)`
(iii). `underset({:[(18 mmol (Yield=100%)),(36 mmol (yield=50%)):}])(Zz(s)+H_(2)SO_(4)(aq)to)ZnSO_(4)(aq)+underset((18 mmol))(H_(2)(g))`
mmoles of `H_(2)SO_(4)` required `=36`
`therefore0.2MxxV_(mL)=36`
`V_(H_(2)SO_(4))=180mL`