Percentage of Sulfate in Fertlizer (1 Viewer)

[bEAbEA]

I was just wondering, when anyone did the sulfate content of lawn ferlilizer, did you get a really high percentage. Our class has done ours repeatedly, but we alwasy get numbers around 40% sulfate ,when the packet says 17%.
If you got a decent percentage, can you please post up your method.
Thanks

 

[ZeGoat]

You should try the prac again with a different source of fertiliser if you really want the results on the packet, but really it shouldnt matter as long as you can do the calculations and understand the whole procedure to do the prac.

In our class, we measured the sulfur content in the fertiliser and received a result of 5.7% compared to the value of 5% indicated on the package.

 

[Jaydels]

The first time I did it I got like over 60%. We left the filter paper with the residue on the window sill for about a week and then weighed it again.....I can't remember what we got but it was more realistic. It's possible that the residue still contained a high water content, so if you can try waiting a while before you weigh it.

 

[Jumbo Cactuar]

Window sill ??!! LOL. Once you get your hand on a dessicator you'll see where I am coming from. They aren't too good for bumping up your yield though!

 

[currysauce]

we got about 45%

 

[richz]

yeah the % u are finding is the sulfate content, the package gives the % of sulfur

 

[Templar]

Window sill ??!! LOL. Once you get your hand on a dessicator you'll see where I am coming from. They aren't too good for bumping up your yield though!

You need an oven. We left products in a dessicator for a week and still got unrealistic yield (95-100%, and in a few cases, >100%).

 

[Jumbo Cactuar]

Did you use a hirsch funnel first? Was it a reduced pressure dessicator? Argh, do a MP test for purity before mocking the awesome powers of the silica!!! OK, admitedly it took 2 weeks to dry 6 grams of acetanilide, but I wouldn't have thought barium sulphate was THAT resilient...

On second thoughs it melts at 1580C so I think the benchtop MP test is out of the question...!

 

[azza_3761]

We got 75% of total potential yeild