How many grams of citric acid instead of propionic acid?

[easypeasyac]

To adjust the pH of the mixture, 5 ml of propionic acid was added to 1 liter of mixture. But I want to use citric acid instead of propionic acid. How many grams of citric acid should I use instead of 5 ml of propionic acid to have the same effect on pH?

Is it possible to make such a calculation without measuring with a pH meter?

[ChenBeier]

Datas of propionic acid missing. Concentration, percentage. If this is known convert ml to g by using specific gravity. Then convert to mole.
Citric acid is a tricarbonic acid, so you need 1/3 of mole. Convert this back to mass by using molar mass of citric acid.

[easypeasyac]

Hello;
Sorry for the missing information.
According to bottle;
Propionic acid is ACS reagent, ≥99.5%. Density: 0.992 g/cm3

So 5 ml propionic acid is equal to 4.96 g propionic acid

Molar mass of propionic acid = 74.078 g/mol
4.96 g propionic acid = 0.0669 mol

Molar mass of citric acid = 192.124 g/mol

At this point, I'm not sure I understood your message correctly and made the calculations correctly.

0.0669 mol citric acid = 12.853 g
12.853/3 = 4.284 g

Then, if I use 4.28 g of citric acid instead of 4.96 g of propionic acid in the mixture, will I get the same result at the final pH value?

[ChenBeier]

Theoretical yes.
But citric acid is also a buffer. To get right value use a pH Meter and adjust pH.

[easypeasyac]

Thank you.

I'm just asking to get detailed information about the subject.

Molar mass of H₂SO₄ = 98.08 g/mol
0.0669 mol HCl = 6.561 g
The maximum concentration of H₂SO₄ in aqueous solutions is 98% (w/w)
In this case, I should use 6.694 grams of sulfuric acid (98%) instead of 4.96 grams of propionic acid.

But isn't sulfuric acid a much stronger acid than propionic acid? But even though it was strong, I had to use it more.

Isn't this calculation you gave valid for all acids? Which topic article should I read to get more detailed information about this topic?

Thank you again.

[ChenBeier]

You have to compare pkS values.
And propionic acid and citric acid are weak acids, sulfuric is a very strong acid.
And it also matters what is in the water. If you have strong or weak bases.

[tommchris]

To determine how many grams of citric acid can replace propionic acid in a given context, we need to consider their chemical properties, particularly their acidity, since both are used to adjust pH in applications like food preservation, cosmetics, or chemical processes.

[ChenBeier]

Already discussed. No need to fill with more unnecessary words.