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Hydrogen peroxide vols?

I've searched through threads but they are not helping.

I did some practical and I need to work out my overall concentrations of hydrogen peroxide that I used but I am finding it confusing.

This is what I have used and how I am in a pickle.

I used 25mls of water to 1ml of 20vol h2o2. Does this dilute the h2o2 in my new overall concentration (well yes it does)

And then ive reduced the water and increased the hydrogen peroxide.

So 24ml water + 2ml 20vol h2o2
23ml water + 3ml 20vol h2o2
22ml water + 4ml 20vol h2o2
21ml water + 5ml 20vol h2o2

???

Reply 1

charco

Study Forum Helper

you can use the 'vol' of the H2O2 just like any other measure of concentration. If you do a dilution then you can calculate the new concentration from simple ratios.

initial concentration = 20 vol

25cm3 water to 1 cm3 of H2O2 means that the H2O2 now occupies 1 part in 26 (25+1)

therefore its new concentration is now 1/26 x 20 vol

The new concentration is calculated by (volume H2O2)/(total volume) all multiplied by the initial concentration of the H2O2 in vol