What

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Whats In Your Water??
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How do we know whats in our water?

• Extraction - Get the stuff you want out of the
  sample
• Separation - Separate the stuff you want from
  interferences, as well as from each other to
  isolate them

• Detection - Find some unique property of the
  stuff you want
• Quantification - How much is there

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Decide on Your Method
This will depend on
Properties? Hydrophobic or Hydrophilic

• What youre looking for (Compounds of Interest)

• Where you want to look for it (Matrix)

What kind of interferences are you dealing with?
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Extraction

• Remove your compounds of interest from the matrix
  by dissolving them in a solvent in which they are
  miscible

What would we need to know to do this?
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Separation - Chromatography

• A way to separate things in a mixture based on
  how similar they are to a solid material

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Chromatography Terms

• Mobile Phase - Moves through stationary phase
  Contains your sample
• Liquid
• Stationary Phase - Doesnt move
• Solid

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Chromatography Terms
Solvent with Compounds dissolved
Effluent
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Solid Phase Extraction (SPE)
Wheres the stationary phase?
What about the mobile phase?
1 Conditioning Column
2 Sample Loading
3 Solvent 1
4 Solvent 2
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So, whats going on here??
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What do we know about water?
Polar
Hydro (Water) philic (Loving) Things are similar
to water (i.e. polar)
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What do we know about oil?
Hydro (Water) phobic (Fearing) Things are NOT
similar to water (i.e. non-polar)
Non-Polar
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Definition

• Separation of electric charge

A Polar Bond
A polar molecule
Electrons pulled this way
Unequal pulling
Difference in electronegativity between atoms
Electrons not shared equally
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Definition

• No significant separation of electric charge

All Non-Polar Bonds
A Non-polar molecule
Equal pulling
No difference in electronegativity between atoms
Electrons shared equally
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Definition

• Separation of electric charge

Polar Non-polar Bonds
Molecule Has Some Polarity
Unequal pulling

Electrons pulled this way OVERALL
Non-polar region
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Think of Polarity in RELATIVE Terms
Hexane
Water
Isopropanol
gt
gt

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Like Dissolves Like

• Strongly polar molecules can even Hydrogen Bond
  -- The Ultimate Polar Interaction!

d-
O
H
H
d
d
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More Similar Interactions ? More Soluble
H-Bonds
Non-Polar Interactions
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In The Column...
Non-Polar
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How might these concepts connect to something
like Kool-Aid?
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To The Lab!
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Helpful Hints

• Group Organization
• 1 Data Recorder - Records all data and
  observations in the data table page of your lab
  handout
• 1 Solution Adder - Adds the solutions to the top
  of the column with a syringe
• 1 Solution Manager - Prepares and give solution
  tubes to Solution Adder Keeps track of what
  solution to add next by following the procedure
• 1 Column Manager - Keeps the column in proper
  position and over the correct tube number Pushes
  the solutions through the column with the plunger
  after the Solution Adder has added them

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Example
Solution Added
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H20
H20
Kool-Aid
Glucose
___
__
___
___
___
_ _
___
___
First non-polar solvent pulled red dye from the
Kool-Aid on the column
Hypotheses for whats happening
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Column Technique Demonstration
Tip
Long End
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Lets get started!...
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Group Differences??

• Come up to the front of the room as a group and
  share your groups observations and hypotheses
  about why this happened
• All other groups should record the different
  groups observations

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Group Differences??

• Now, reframe your hypotheses and explanations in
  light of the information on you Kool-Aid packet

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Group Differences??
Grape
Cherry
Orange
Lemon-Lime

• Now, reframe your hypotheses and explanations in
  light of the information on you Kool-Aid packet

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Rank Relative Polarity
Water
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10
70
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Solvents?
Yellow
Red
Blue
Dyes?
Polar
Non-Polar
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
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10
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Solvents?
Yellow
Red
Blue
Dyes?
Water
Polar
Non-Polar
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
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70
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Solvents?
Yellow
Red
Blue
Dyes?
Water
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Polar
Non-Polar
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
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Solvents?
Yellow
Red
Blue
Dyes?
Water
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10
Polar
Non-Polar
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
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Solvents?
Yellow
Red
Blue
Dyes?
Water
5
10
20
Polar
Non-Polar
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
Solvents?
Yellow
Red
Blue
Dyes?
Water
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10
20
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Polar
Non-Polar
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
Solvents?
Red
Blue
Dyes?
Water
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10
20
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Polar
Non-Polar
Yellow
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
Solvents?
Blue
Dyes?
Water
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10
20
70
Polar
Non-Polar
Yellow
Red
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Rank Relative Polarity
Solvents?
Dyes?
Water
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10
20
70
Polar
Non-Polar
Yellow
Red
Blue
Remember Molecules stay with their closest
polarity Column Non-polar Solvents polar to
non-polar
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Why Do The Dyes Act Differently?
They have different polarities!!
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What Makes a Molecule Polar?

• Difference in charge distribution
• Ionic groups
• Electronegative groups
• Molecular symmetry
• Size

Cl, Br, O
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Larger
Small, Many OH Groups to H-bond to Water
Relative Polarity Glucose gt Yellow gt Red gt Blue
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Image Credits

• Slide 1
• http//jewelcityjuice.wordpress.com/2009/10/15/saf
  ety-tip-of-the-day/
• http//princetonwaterwatch.wordpress.com/2009/09/0
  4/calculate-your-water-footprint/
• Slide 6/7
• http//www.biotage.com/graphics/9222.jpg
• Slide 8
• http//www.biotage.com/graphics/9223.jpg
• Slide 10
• http//upload.wikimedia.org/wikipedia/commons/f/f9
  /3D_model_hydrogen_bonds_in_water.jpg
• Slide 11
• http//www.bbc.co.uk/schools/gcsebitesize/science/
  images/aqa_science_13.gif
• Slide 16
• http//www.columbia.edu/sf2220/TT2008/web-content
  /Images/yes20Kool-AidMan.jpg

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