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Volatile Acidity Calculations

See also record sheets for formula




				Titre (ml) x C (M) x 60
Volatile Acidity (in g/L as per acetic acid equivalents)		=		-----------------------
.				V (ml)



Where -

Titre = the number of mL of 0.01 M NaOH required to neutralize the volatile acidity in the the sample volume (V) - blanc titre.

C= the exact molar concentration of the 0.01 M NaOH solution.

60 is the conversion factor converting moles/L of acetic acid to g/L

V = Volume in mL of the sample size used.


E.G.



				9.8 ml x 0.0092 M (moles/L of NaOH) x 60 (g/mole of acetic acid)
VA (g/L)		=		-----------------------
.				10 mL



moles of NaOH required = moles of acetic acid neutralized

therefore the units mole cancel out and the units mL also cancel out leaving the units required g/L

and the VA in this example = 0.54 g/L as acetic acid

• The molecular weight (MWof acetic acid is calculated by adding the atomic weights of all the individual atoms that acetic acid (CH₃COOH) is composed from.
  
  ie The MW of CH₃COOH
  
  = (C = 12) + (H₃ = 3 * 1) + (C = 12) + (O = 16) + (O = 16) + (H =1)
  
  = 60
  Since MW represents the number of grams (g) of one mole of a substance -
  
  mole/L = MW (g)/L
  
  mole/L acetic acid = 60 g/L