The normality of '30 volume ${\mathrm{H}}_2{\mathrm{O}}_2$' is

1 L of '30 volume ${\mathrm{H}}_2{\mathrm{O}}_2$ ' liberates 30 L of O₂ at STP or (30/22.4) mol of O₂ . From the equation     $2{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

it is obvious that (30/22.4) mol of O₂, is liberated from (60/22.4) mol of ${\mathrm{H}}_2{\mathrm{O}}_2$ , i.e. 2.678 mol. Hence, molarity of ${\mathrm{H}}_2{\mathrm{O}}_2$ is 2.678 mol L^-1 and its normality will be 2 x 2.678 eq L^-1