Hydrogen peroxide

[Labbie]

A teacher would like a PH1 PH4 PH7 PH9 & PH13 with Hydrogen peroxide in the mix. Can any one help me with this.
Has any one done this yet???????

[sunray18]

enzymes right? I did make up those solutions by making buffers of each pH. Another teacher here did it by making various dilutions of weak acids and bases..
but we did NOT make the H2O2 at that pH. we put the potato/filter paper disc into these solutions THEN put them into H2O2 in test tubes.. works! especially the potato cores work really well.

[lada]

Sue, I make up the pH solutions and students add a fixed amount of buffer and H2O2 in each t/tubes, We did liver and potato cores and work well.
If you like I can give you recipe, very easy.
Lada

[Labbie]

Yes please Lada, I would love the recipe,

thank you so much

[lada]

We use pH 3,6,8,11
Set up 4 t/tubes with 3mL of pH solution in each and label.
Add same amount of pureed liver or core of potato in each and add 5mL of 3% fresh peroxide. We add a small amount of detergent to assist the foam forming..
Use pH7(distilled water) as control.

to make pH solutions:
pH1 =0.1M HCl
pH2=0.01M HCl
pH3=0.001M HCl
.
.
pH14=1M NaOH
pH13=0.1M NaOH
pH 12=0.01M NaOH
.
.
Hope this helps
Lada

[Labbie]

Hi Lada, You are the VERY BEST, thank you so very much, I have tested it all out, and now are very happy. Well Done you.

[lada]

Glad to help,
Lada

[Labbie]

Want would people suggest for PH5 Hydrogen peroxide, I have PH4 as 6% Hydrogen peroxide, add a little Sodium Hydroxide?

[Xenon]

Yes Labbie, I add drop by drop dilute NaOH continually checking pH with electrode, and magnetic stirrer running as pH scale gets more sensitive closer towards 7.

[labbassistant]

Hi,
One of my teachers has asked for 27% hydrogen peroxide. Does anyone know how I dilute to make this?

[Anna Z]

The bottle you normally buy is 35%...so if it's been open for a bit and not refrigerated it will no longer be 35% anyway. You could just give them what's in the bottle.

Otherwise (C1) (V1) = (C2) (V2)