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Hello, i would really appreciate it if someone could help me with this problem. I would like to know the pH of citric acid at various concentrations.

2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 20%.

From what i have read it has something to do with its pKa value which for citric acid is: 3.06. The formulas i have seen on wikipedia and other places are too complicated for me to solve and although i have found an on-line calculator it seems very inaccurate.

http://www.sensorex.com/support/education/pH_calculator.html [Broken]

It gives results of:

5% citric acid = 1.87 pH - Lemon juice is 5% and has a pH of around 2.3

Could someone please work these out for me or show me how to do it.

p.s. 50g per litre is 5% right? or 50g per 0.950 litre... (of water)

Also this is not for my homework.

2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 20%.

From what i have read it has something to do with its pKa value which for citric acid is: 3.06. The formulas i have seen on wikipedia and other places are too complicated for me to solve and although i have found an on-line calculator it seems very inaccurate.

http://www.sensorex.com/support/education/pH_calculator.html [Broken]

It gives results of:

5% citric acid = 1.87 pH - Lemon juice is 5% and has a pH of around 2.3

Could someone please work these out for me or show me how to do it.

p.s. 50g per litre is 5% right? or 50g per 0.950 litre... (of water)

Also this is not for my homework.

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