10.0 mL of a hydrogen peroxide solution is diluted to 100.0 mL. A 20.0 mL portion of the diluted solution needs 15.0 mL of 0.0200 M acidified KMnO4. The volume strength of the original solution (volume of O2 at STP given by 1 mL on decomposition; molar volume 22.4 L) is:

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$10.0 mL$ of a hydrogen peroxide solution is diluted to $100.0 mL$ . A $20.0 mL$ portion of the diluted solution needs $15.0 mL$ of $0.0200 M$ acidified $KMnO X_{4}$ . The volume strength of the original solution (volume of $O X_{2}$ at STP given by $1 mL$ on decomposition; molar volume $22.4 L$ ) is:

In the

20.0 mL

portion,

H X_{2} O X_{2}

= 15.0 \times 0.0200 \times 5/2 = 0.750

mmol, so the diluted solution is

0.0375 M

and the original is

0.375 M

. Since

2 H X_{2} O X_{2} \to O X_{2}

1 M

corresponds to

11.2 V

. Volume strength

= 0.375 \times 11.2 = 4.2 V