Question: aqueous cream is preserved with 1 ww phenoxyethanol calculate the...

Aqueous cream is preserved with 1% w/w phenoxyethanol. Calculate the amount of phenoxyethanol that must be added to the cream formula to produce 100 g of cream with an overall phenoxyethanol concentration of 1% w/w.

 

Coal Tar solution  3%

Salicylic acid        2%  

Glycerol                5%

Aqueous cream to 100% 

(wt/ml of coal tar solution = 0.79 g , glycerol = 1.26 g )