SO4-2 - Am I looking or the figure as sulphur or as sulphate?

[mattsearle]

I am in the UK where getting a water report doesn't seem to be as simple as in the states. I have a friend who works at my local water company and he managed to get a friend who works in the lab to do me a water report.

Under 'sulphate' I have 2 figures - 'as sulphur - 32.496ppm' and 'as sulphate - 97.49ppm'. I am just wondering which is the figure that I should pay attention to when figuring out my water additions, sulphate/ chloride ratio etc please?

Thanks

 

[dmtaylor]

Use the sulphate number (97), not sulphur.

Same would go for chloride. Use chloride, not chlorine or hypochlorite or chloramine, if stated. These are all different molecular structures with completely different properties.

 

[jerbrew]

use the sulphate number

 

[mattsearle]

That's great I assumed it would be the sulphate, but both were under the sulphate heading so I wanted to make sure before making any additions

 

[ajdelange]

Use the sulphate number (97), not sulphur.

Same would go for chloride. Use chloride, not chlorine or hypochlorite or chloramine, if stated. These are all different molecular structures with completely different properties.

Let's be careful here. Sulfate as sulfur and sulfate as sulfate are the same molecule with the same properties. It is just that in the former case they are reporting only the weight of the sulfur in the SO4-- ion (about 1/3 of the total) and in the latter they are reporting the weight of the entire ion (including the oxygen).

When it comes to chlorine/chloride the latter refers to the chloride ion but when 'chlorine' is specified they are referring to the available chlorine as chlorine whether it be the chlorine in a hypochlorite ion or the the chlorine in one of the chloramines.