Question

Sandy completed pH and fecal coliform tests on water samples from the pond in her backyard. She reported the results in the following charts. What can you conclude about the water quality of Sandy's pond over the past year? Explain.

Answer 1

@jim_thompson5910 ??? Would you happen to know?

Answer 2

you have 2 charts, one comparing time vs pH and another comparing time vs colony density

Answer 3

do you know how to read these charts?

Answer 4

No.

Answer 5

the first chart shows a series of vertical lines, these vertical lines look like the range of the pH for a given month

eg: in March, the vertical line stretches from 6.3 to 7.5, so the pH in March ranges from 6.3 to 7.5 (do you see how I'm getting this?)

Answer 6

Yes. But I mean, is it a good or bad thing the higher it gets?

Answer 7

pure water has a pH of 7

Answer 8

anything less than a pH of 7 is acidic

Answer 9

& anything more?

Answer 10

anything more than 7 is alkaline (or basic)

http://www.elmhurst.edu/~chm/vchembook/184ph.html

Answer 11

oh. okay so what about the 2nd chart?

Answer 12

so this water is slightly acidic because the pH is slightly less than 7 (it looks like)

Answer 13

and the readings are pretty consistent (ie the intervals are small as time goes on)

Answer 14

Oh okay. I think I know what to write now, thanks :D

Answer 15

for the second chart

Answer 16

the vertical axis is the density or concentration of bacterial colonies

so as time goes on, the concentration increases and peaks out at June, but the colony concentration sharply decreases from June to July and then it slowly starts to increase again

Answer 17

so what did you write as your final answer? i still don't understand.