[claire]

Hi,
i have a chemistry task which says we have to work out a method to determine the sulfuirc acid content of lawn fertilizers but i have no idea how to do this.
would you please be able to suggest a method that would work for this investigation?
thanks  

[AWK]

Gravimetric analysis with barium sulfate as precipitate will work

[kevins]

A spectrophotometric method is a alternative method for the determination of sulfate.

1. Weight a portion of sample and dissolve in water.
2. Filter the insoluble and collect the filtrate.
3. Transfer the filtrate to a volumetric flask and top up with water.
4. Take a known portion (~25mL) of dissolved sample and add 5 mL acidified 10% BaCl2 solution.
5. Measure the absorbance against the reagent blank @450nm.

Please try