phosphates question (1 Viewer)

[abdul92]

what did evry1 get for part 1???/

 

[sam5]

what did evry1 get for part 1???/

i just found the averages of the creek samples.

The only one that failed the safety requirement was stream 2.

I said it may have been located near a farm, and received fertiliser or effluent runoff, causing more phosphates.

For the third part i said how phosphates cause eutrophication via microbial decay, less sunlight in the water and less direct O2 dissolution. Therefore it affects DO and thus a water quality issue.

 

[mR sinister]

^ +1
Same here, except for eutrophication i wrote how it kills aquatic life, and chokes water.
it was only for 2 marks, so im guessing mentioning wat eutrophication is and what it does would get u 2/2

 

[boxhunter91]

First part was preety stupid.
2nd part i defined eutrophication and then said increase in BOD and decrease in DO which leads to death of aquatic organisms.

 

[Aerath]

Pretty much what boxhunter91 said. I didn't mention BoD, but I mentioned decrease in DO, and then went on to say if algal blooms occured, plants wouldn't be able to photosynthesise etc.

 

[boxhunter91]

Hammered it aerath

 

[postcardsfrom]

Yeah I found the averages of the absorbance values, then read the approapriate concentration values off the graph. I said the stream with the low concentration was clean and unpolluted, the stream with the near-to-limit value was probably from a town, receiving sewage run-off. The one over the limit i said was due to fertiliser run-off from agriculture. For the second part, I went on a bit about cyanobacteria (blue-green algae) and about how it blocks sunlight and stuff.

Good times,

 

[imoO]

What do you mean averages?

Did i not read the question or something?

 

[Aerath]

They asked you to find the mean of the absorbance levels given.

 

[boxhunter91]

LOL didnt you see the first part?
I made sure all my answers were to 3 sig figs.

 

[Live Laugh Love]

Sameee!

 

[AJ92]

Yeah first part was above the graph - to find concentrations it was
concentration = absorbance/2.75