April 03, 2020, 08:20:23 PM
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### Topic: Volumes for pH adjustment  (Read 136 times)

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#### MarinaSchnider

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##### Volumes for pH adjustment
« on: March 16, 2020, 04:14:46 PM »
How do I calculate the volume of KOH 50% to be added into a pH=4 solution in a volume of 1 liter in order to raise the solution's pH to pH=6?

#### chenbeier

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##### Re: Volumes for pH adjustment
« Reply #1 on: March 16, 2020, 04:30:33 PM »
Calculate the H+ concentration for both pH.
Then calculate the difference of them. This is amount what has to be neutralized.
Then you have to figure out what is the concentration in 50% Solution KOH and work it out.
The problem is, what kind of acid do you have. Some work as buffer.

#### MarinaSchnider

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##### Re: Volumes for pH adjustment
« Reply #2 on: March 16, 2020, 04:34:05 PM »
The acid is unknown...

#### Borek

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##### Re: Volumes for pH adjustment
« Reply #3 on: March 16, 2020, 06:15:32 PM »
How do I calculate the volume of KOH 50% to be added into a pH=4 solution in a volume of 1 liter in order to raise the solution's pH to pH=6?

The acid is unknown...

Not enough information then (unless you are expected to assume it is a strong acid, 100% dissociated).
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