Brine
Solution - Experimental Lake
Group
Names: _______________________________________________
Date:
_______________________
Knowledge
Base
When the
conductivity of a lake or river changes, it indicates there has been
some sort of disturbance. The disturbance might result from natural
or human activities, or it might be caused by physical, chemical, or
biological factors.
Experimental
Design
- How
did you manage to create an experimental "lake" with at least
200 ml of water with a 1.5 mM initial salt concentration? (Explain your
thinking process and calculations.)
- Initial volume of your experimental "lake" _____________
Initial conductivity of the lake _____________
Data
Collection
- Volume
of the lake after the effluent was added _____________
Conductivity
of the lake after the effluent was added _____________
Data
Management and Analysis
- By
how many microsiemens did conductivity increase? _____________
- Use
your standard curve graph or the regression equation to determine the
salt concentration before and after the effluent was added.
Concentration
of salt in lake at the start ______________ Concentration
of salt in lake after effluent addition ______________ Increase
in mM of salt concentration ______________
- How
many milligrams of salt were added to your lake by the effluent _____________
- What
was the percent increase in the salt concentration in your lake?
Interpretation
of Results
- How
accurate do you think your calculations are?
- Hypothesize
what effect a similar amount of salt would have on plants and animals
in a real lake.
- How
might salt concentrations affect human use of the lake?
Reporting
Results
- Ask
each of the other small groups for their results and record how many
milligrams of salt were added to each experimental lake.
Group 1
Group 2
Group 3
Group 4
Group 5
Group 6
- Rank
the groups according to the amount of salt added to each lake.
Least
salt added
_____________
_____________
_____________
_____________
_____________
_____________
Most salt added
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