How Can %w/v Be Converted to pH?

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xyla
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Hi. I would like to ask help on what is the equivalent of % w/v to pH?
Say for example: What is the pH of 4% w/v?
 
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xyla said:
Hi. I would like to ask help on what is the equivalent of % w/v to pH?
Say for example: What is the pH of 4% w/v?
Your question is a little vague. o_O

In any even, pH is based on the activity of hydrogen ions in an aqueous solution:

http://en.wikipedia.org/wiki/PH

As can be seen from this article, different materials in solution have different pH values. The pH of pure water is defined as 7. A pH value less than 7 indicates an acid, while a pH value greater than 7 indicates a base.
 
%w/v is the acetic acid concentration in an acidic solution, vinegar, and that is the "unit" used when you are titrating the solution. Now I want to use a pH meter but I don not know what is the equivalent in pH of 4% w/v or even how to derive it. I need an "accepted" pH of vinegar to see if my vinegar conforms to the set standards.
 
xyla said:
%w/v is the acetic acid concentration in an acidic solution, vinegar, and that is the "unit" used when you are titrating the solution. Now I want to use a pH meter but I don not know what is the equivalent in pH of 4% w/v or even how to derive it. I need an "accepted" pH of vinegar to see if my vinegar conforms to the set standards.
According to this article:

http://en.wikipedia.org/wiki/Acetic_acid

a 1.0 M solution of acetic acid (about the strength of household vinegar) has a pH of about 2.4. I have no idea if a 1.0 M solution is equivalent to 4% w/v for the acetic acid in vinegar. :sorry:
 
thanks. :smile:
I'm thinking that if there is a way to convert %w/v to mole, the pH can be calculated but I don't know how and I did several researches but got no answer...