[Golden_4_Life]

Whenever I peruse the literature for methods of analysis, invariably there will be a calculation formula cited by the author that contains a 'conversion or correction factor' that does not make ''conventional" sense in the normal chemical usage.  Typically, the such "factors" are numbers that are used to make the equation's answer appear sensible; however, the origin of these such 'factors' is oft dubious (and this is putting in generously).
I found a method for the titrimetric determination of benzalkonium chloride in aqueous cleansers by using sodium lauryl sulfate as the titrant.
So, the % benz.chlor = [u](titrant volume)(normality of titrant)(FACTOR)[/u] this answer divided by sample weight in grams.

The authors said that the FACTOR = (molec. wt of SLS / Equivalents) / 1 .

They said the FACTOR value was = 36.

How on God's Green Earth did they get this value
  A mole snak if you can explain--i hav no earthly idea.

[MOTOBALL]

R4N+ Cl-   +    C12H25OSO2O- Na+ gives C12H25OSO2ONR4  +  NaCl

1 mole (340 g)  Benzalkonium Cl  reacts with 1 mole (288 g) SLS

Using,             n1 v1 = n2 v2

Then,      n1 (normality of R4N+ Cl- )  = (n2 v2)/v1

N1 = [(g/L of SDS) x vol. of SDS]/ [288 x vol. of cleanser] = [g/L of R4NCl]/340

Then,      

 g/L of R4NCl = 340 x [(g/L of SDS) x vol. of SDS]/ [288 x vol. of cleanser]

then,

Wt-%  of R4NCl = [340/10] x [(g/L of SDS) x vol. of SDS]/ [288 x vol. of cleanser]

Even if MW is 360 (not 340) for R4NCl, then factor is [360/10]/288 = 0.125

I also cannot understand where the Factor = 36 comes from

Motoball

[Golden_4_Life]

Your effort is appreciated--enjoy your snack!