1. Forensic Science (Chemistry option) with a Chemistry minor
Loren Williams   
Forensic Science (Chemistry option) with a Chemistry minor
Loren Williams
Studying Forensic Science and Chemistry--senior
Going to be a Course Assistant for a trace evidence class

2. Questioned Documents Intro and History Handwriting Activity 2
Individual Characteristics
Activity 3
Analysis
Activity 4
Picture:

3. What is a Questioned Document?
A questioned document is one in which a document in its entirety, or in part, is subject to question as to authenticity and/or origin.
Any signature, handwriting, typewriting, or other marks
--in the broadest definition, a document is any fixed method of communication between one individual and another
--pre WWII the inks and papers, typewriters, copiers, and instruments used to examine questioned documents were simple compared to today
--post WWII everything started to develop into what we know today—new inks, and many different types of copying machines
--this growth in technology also led to a growth in crimes of forgery and document alteration
Most people do not realize the scope of the phrase “questioned document.” It’s easy to envision a signature on a will, a check or a contract. But questioned documents can be anything that constitutes a document, from a typewritten letter, to a dollar bill, to a postage stamp to a receipt, or even a brand on cattle.
IN the broadest, all-encompassing terms, a document is any fixed method of communication between one individual and another.
A questioned document is one in which a document in it entirety or in part, is subject o question as to authenticity and/or origin.
The examinations required to answer the questions may be complex, encompassing the method in which the document was created, the ink or machine printing upon it, the date it was written, the company responsible for the document's production, what sequence it was written in, and finally, the identification of the author. The examiner may first have to restore the item after it has been burned, altered, obliterated or torn.
Sixty or seventy years ago, handwriting, inks and papers, typewriting, machine copying, counterfeiting, commercial printing processes, and analytical instruments for the examination of questioned documents were comparatively simple. The post World War II era brought on a remarkable proliferation of new inks, writing implements and papers, novel typewriting systems, new printing techniques, and an explosion in the numbers and types of copying machines. This was then followed by a wave of computers, software, scanners, high-speed printers and fax machines. While these have revolutionized the production, transmission, and storage of documents, it has also caused a dramatic increase in document problems, and a necessary broadening of techniques and instruments used by a forensic document examiner.
Crimes of forgery and document alteration have developed along with these new technologies and advancements.

4. Most Common Questioned Documents
Voter registration
Passports
Petitions
Threatening letters
Suicide notes
Lottery tickets
Letters
Checks
Drivers Licenses
Contracts
Wills
--during a crime, there is often a paper trail
--it is the job of the questioned document examiner to authenticate any one of these
--they might need to figure out who wrote the item originally, who received it, or if it was changed or forged in anyway
During the commission of a crime, there is often an extensive paper trail, from handwriting to printed receipts to other documentary evidence.
The most common questioned documents we see are things like letters, checks, drivers licenses and other forms of ID, contracts, wills, voter registration, passports, petitions, threatening letters, suicide notes, and lottery tickets.
A questioned document examiner may be asked to authenticate any one of these things. They may need to figure out who originally wrote the item, who received the item, if the item was changed in any way, or if it is a forgery.

5. Cases Involving Questioned Documents
Forgery
Counterfeiting
Mail fraud
Kidnapping
Con games
Embezzlement
Gambling
Organized crime
White collar crime
Art crimes
Theft
Robbery
Arson
Burglary
Homicide
Serial murder
Psychological profiling
Deviant sex crimes
--any crime can have a questioned documents involved with it, but these are the most common
--if you become a questioned documents examiner, you can count on working these types of cases
While any crime can have a questioned document component, these crimes seem to have the highest number of questioned documents involved Forgery
Counterfeiting, Mail fraud, Kidnapping, Con games, Embezzlement, Gambling, Organized crime, White collar crime, Art crimes, Theft, Robbery, Arson, Burglary, Homicide, Serial murder, Psychological profiling, Deviant sex crimes
If you become a questioned documents analyst, you can count on working this type of crime, and looking at evidence from these types of situations.

6. Questioned Document History
Rural to urban
Advances in ink technology
Penmen
--questioned documents is an area that knowing the history comes in handy
--lifestyles changed from R-U
Allowed for more opportunities in education
Advances in ink technology
--this led to an ink and paper type of society instead of a money and handshake society
--now that more documents were circulating society, the need grew for people that could distinguish the authenticity of these documents
--Penmen were the people for the job
a penman is a person with professional skill sets in the area of penmanship of various types
they were trained at a college level
very desired at the time because it was before typewriters
hired to keep books and records, write policies, and execute certificates
testified they could differentiate handwritings and this was accepted in courts because they used scientific methods (side by side comparisons)
Now, remember when I talked about forensic anthropology, and I mentioned that there are some types of forensic disciplines that want their experts to know the history? Yep, questioned documents is one of them.
Question Document History
Lifestyles changed form rural to urban
With both education and ink advances, it became more of an ink and paper society
Instead of exchange of money and handshake it became the exchange of money and a signature
Need grew for people that could distinguish the authenticity of a document
Attorneys would look towards Penmen for help in these cases
People with Professional skill sets in the area of penmanship of various types
People were trained at the college level in hand-drawn letterforms
Before typewriter it was a booming career path
Were hired to keep books, records, write policies, execute certificates
They testified that they could tell the difference in handwriting
Accepted in court because they used scientific methods
Side by side comparison

7. Questioned Document History
Dreyfus Affair
Albert Osborn
Questioned Documents
One case set back the discipline
Known as Dreyfus affair
Alfred Dreyfus was a French artillery officer who was charged with treason based on some letters he had allegedly written
In 1894, the French Army’s counter-intelligence section became aware that new artillery information was being passed to the Germans by someone high up in the ranks
Suspicion fell on Dreyfus, who was arrested for treason on Oct. 15, 1894
On January 5, 1895 he was convicted and sentenced to life in prison
Two years later, a military intelligence officer reported he had found evidence that someone else was the real traitor, but the military officer was silenced by being transferred to the desert of Tunisia
The cover up and Dreyfus’s possible innocence leaked to the press and it caused a huge uproar
Dreyfus was pardoned by the French president in 1899, but was officially still considered a traitor
Through investigation of the original letters and hand writing analysis, it was proven that a different man sent information to Germany and Dreyfus was reinstated in rank and eventually knighted
Albert Osborn
American handwriting expert
Published Questioned Documents in 1910
Noticed that there needed to be a basis of handwriting knowledge
Did this through inviting penmen throughout the country to share their experiences and expertise in handwriting cases in 1913
This led to the founding of the American Society of Questioned Document Examiners in 1942
Because of all of this, Osborn is considered the pioneer of the question document field
His knowledge became integral in the famous Lindbergh baby case

8. Questioned Document History
Lindbergh Kidnapping
Lindbergh baby case:
--20 month old toddler was abducted from his family home in New Jersey on March 1, 1932
--Very little evidence was initially found in the case until a ransom note was found by the family on the window sill, wanted $50, 000
--A second note arrived through the mail on March 6th, and determined by Osborn to be authentic, now wanted $70, 000
--There were many more notes delivered and found various ways
--Lindbergh paid the ransom in April without notifying police, and was sent to a pier where he was told the baby was being held
--The baby was not there
--In May, the babies body was found a short distance from the family home, cause of death skull fracture
--A truck driver found the body when he went to pee near the Lindbergh home
--The body was badly decomposed, had a skull fracture, and the left leg and both hands were missing due to animal feeding
--There were indications that someone had attempted to bury the body
--Investigation lasted two years, focused on tracking the ransom money which eventually lead to Richard Hauptmann, who had evidence in his house including paper that matched the letters, he was sentenced to death
--Analysis of his handwriting proved to match that on the notes
--Widely accepted because of Osborn’s extensive use of scientific techniques.
--Result of his work and national attention, the QD field was included in many Federal and State Agencies.
Now called Questioned Document Examiners

9. Catch me if you can https://www.youtube.com/watch?v=N4yutQ8YGHo
21:10-21:32
26:20-28:00
--He was just evicted from his apartment for not paying rent and having all his checks bounce
--21:10—he decides to attempt to forge a check
--but no one will deposit/cash it for him because they don’t know him, he sees a pilot and gets an idea from that to fake being a pilot
--26:20—continues forging checks, but now as a Panam Pilot (more legit)

10. Handwriting

11. Questioned Document Analysis
Ink Examination
Paper Examination
Machine Examination
Handwriting Analysis
Now a days, questioned document analysis involves analysis of the document itself which includes
Ink examination
Paper examination
Machine examination
The typewriter or printer
And handwriting analysis

12. What Questions are Important?
What pen wrote this? What type of paper is it written on? Has it been altered?
The major questions that we ask a questioned document analyst:
What pen wrote this
What type of paper is it written on?
Has it been altered?

13. Graphologist
--a graphologist is someone who profiles character or personality by drawing conclusions from characteristics in handwriting samples
--as you can see, different traits and behaivors are associated with the way the letters look
--some people get questioned document analysis confused with graphologists
--they are very different though
graphologists do not compare handwriting to determine authenticity or origin like a questioned document analyst would
there are several systems of graphology, but none are considered scientific discipline, but there are some things that can be supported scientifically, some handwriting can be affected by age or illness
Some people get questioned document analysis confused with people who try to analyze handwriting
These people are called Graphologists
They profile character or personality by drawing conclusions from certain types of characteristics in the handwriting sample
They do not compare handwriting to determine authenticity or origin
Most graphology lacks scientific support
Some of the principles of graphology supportable
Things like handwriting can be affected by illness, old age, etc.
There are several systems of graphology, but none of them are considered scientific disciplines.

14. Question Document Examiner
Studies scientifically the whole document
The first QDE were called “handwriting specialists” because that was the primary means of agreements or contracts.
--if we compare a graphologist and a questioned document examiner we see the graphologists focuses on handwriting for personality reasons and the QDE focuses on the entire document for authenticity and origin reasons
Compare this with a Questioned documents examiner
This person studies scientifically the whole document in order to recognize the source or other evidence that can determine authenticity of the document in question
The first question document examiners were called hand writing specialists because that was the primary means of agreements or contracts

15. Handwriting Theory Handwriting is just as unique as your fingerprints
Difference between fingerprint and handwriting
Fingerprints are permanent and do not change
Handwriting is a learning process
The theory behind studying handwriting is that handwriting is just as unique as your fingerprints
There are some major differences:
Fingerprints permanent
Handwriting: is a learning process
It lends itself to change as a normal process
A child is taught using the model of the alphabet
--The child does not have handwriting of his own because he is creating an artistic representation
--Child gets better at remembering letter formations and draws them from memory
--This is where variations and deviations come from
--He/she begins to develop own handwriting
--It’s not until individual characteristics become habitual and repetitious that handwriting has become mature
--This is when the person can write as a subconscious act
--It’s at this point where we can make the comparison from fingerprint to handwriting
--Handwriting is unique to an individual

16. Fingerprint vs. Handwriting
When are fingerprints and handwriting comparable in uniqueness?

17. Handwriting Characteristics
Class Characteristics
Handwriting systems: Spencerian, Palmer, Zaner-Bloser
Fonts: SpenCERIAN, Palmer, Zaner-Bloser
Individual Characteristics
Handwriting characteristics
Like all evidence, handwriting has both class and individual characteristics
--Class characteristics: similarities between individuals who learned the same type of writing systems
--Serve just to narrow down the search when comparing a questioned document to standard writing systems
--Handwriting systems are a collection of letter formations that contain common features, usually created by a teacher/penman and is taught as a pattern
--Handwriting systems are comparable to fonts on the computer
--Some of the most common systems include:
Spencerian — Popularly taught to children in the 1800’s, characterized by fluid lines and connecting letters. This was a necessary system used to keep the sharp edged steel nib pens of that era from tearing the writing paper
The Palmer system—replaced Spencerian method in the late 19th and early 20th century, Created as a less ornate style than the Spencerian method, Became the most popular method in the U.S.
Zaner-Bloser—Replaced Palmer method in the 1950s and still used today
--based on the style of writing, some QDE’s can determine a general region a person attended grade school based on their handwriting if it is a unique enough handwriting that wasn’t taught often
--Individual characteristics are characteristics specific to a single writer
Things like skill level, slant or inclination, letter form, movement of pen, letter proportions, height ratios, the I dod, the t crossing, alignment to baseline, etc.
--It’s the combination of individual characteristics that make handwriting unique to a writer
Handwriting systems are a collection of letter formations, typically created by a teacher or penman, that generally contain some common features within similar letter formations. It is a prescribed pattern for emulation as a handwriting style and is taught as part of the educational process. It may be published with accompanying methods of instruction.
Our retention of some of the copybook forms of a handwriting system will continue to a greater or a lesser extent throughout our lifetime. On some rare occasions, a document examiner may be able to closely approximate the writer’s geographic location of his or her primary education by comparing an individual’s writing with little used and localized handwriting systems.
There have been dozens of different handwriting systems used throughout the history of the United States.
Many of these handwriting systems vary only slightly from one to another, and all maintain some basic similarities that everyone can recognize. Our ability to read someone else’s writing even though they were taught a different writing system is contingent upon very similar letter formations between the different systems. If the different systems were so divergent that the letters were totally dissimilar, we would be unable to communicate using the written word. For this reason, the Forensic Document Examiner does not have to know all of the different handwriting systems to recognize a class characteristic. It is in his or her best interest, however, to be familiar with several of the more common systems.

18. Activity 2: Handwriting Analysis
Have ONE team member write a phrase on a piece of paper TWICE (in 2 columns)
Have each team member write the SAME phrase on the SAME piece of paper in each column
Place another piece of paper over it
Make a small mark at the top of all the possible places of each letter (y = 2 top spots) in column 1
Join all the dots with a ruler, cut the paper around the lines, then compare using the light
Place another piece of paper over it the remaining column 2
Draw lines through the middle of each letter that line up with the slope of the letter, compare the slants

19. Activity 2: Handwriting Analysis
Which question matches the sample? (from the handout)
THE SECOND ONE!!!

20. Individual Handwriting Characteristics

21. Handwriting Characteristics
Class Characteristics
Handwriting systems: Spencerian, Palmer, Zaner-Bloser
Fonts: SpenCERIAN, Palmer, Zaner-Bloser
Individual Characteristics
--Individual characteristics are characteristics specific to a single writer
Skill level, slant, letter form, movement of pen, proportions, I dots and T crosses
--It’s the combination of individual characteristics that make handwriting unique to a writer

22. Types of Individual Characteristics
Skill Level
Slant
Form
Movement
Proportions
Height
“I” Dot
“t” Crossing
Loops
Pressure
Baseline Alignment
Pen Lifts
Speed
Embellishments
Entry/Exit Strokes
Retracing
Spelling/Spacing
Format
Case
Individual characteristics:
--Skill level: can best be described as an appreciation of beauty as applied to handwriting
Someone with high skill level produces writing that is fluid, rhythmic, and artistically embellished
Low skill level is hesitating, slowly executing, may contain unpleasing look
--Slant or inclination: The angle of inclination of writing or a letter of writing from the baseline of that writing
May be forward an leaning to the right, or backhand if it leans to the left
May change throughout word
Doesn’t carry as much weight as other individual characteristics
--Form: This is a pictorial representation of a letter or writing movement
A highly visible dissimilarity in the form of the same letter found in both the questioned and standard material is an inherent difference in handwriting
This is the first of the individual characteristics that will receive the document examiner’s close scrutiny
--Movement: This is the manner in which the pen moves in order to form a letter
If a pen moves overhand or clockwise, it’s referred to as Garland movement
If pen moves underhand or counterclockwise, it’s called Arcade movement
Generally need to look at writing under low powered microscope to determine
--Proportions: Symmetry of an individual letter
Using the letter B as an example, is the top bulb the same size as the bottom?
Is one portion of the letter thinner than another?
--Height ratios: Comparison of the height of one letter or letter segment to another letter, usually within the same word or signature
One would expect all capital letters in the same writing system to maintain the same height throughout a body of writing, but the heights of capital letters in an individual’s writing may vary from one letter to another
A capital K may have a slight height advantage over a capital L or Z for example
Same concept used in lower case letters
--The i dot: I dots come in all sizes and shapes—may be horseshoe shaped with an open end up, to the right, down or left, or be simply dots, circles, or dashes. Certain age groups do certain shapes—teenaged girls use hearts
--The t crossing: A t crossing may go from the right to left, left to right, incline up or down, or be horizontal; crossed at bottom or top of the letter; may be connected to another letter
--Loops: Shape, size, symmetry
--Pressure/shading: This is the study of the width of a line as pen pressure varies—may indicate direction of movement
--Alignment to baseline: Relationship of questioned writing to a baseline
--Pen lifts and embellishments: Pen lifts are when the pen or pencil is lifted from the paper and reapplied ot finish a word or sentence
Most people have pen lifts that are likely in their writing
Embellishments decorate writing
Usually found in the beginning of a word
--Speed: Speed is a key indicator for questioned document examination
Fast and slow speeds are difficult to duplicate leaving behind inconsistencies in the writing
--Retracing: is considered fixing a portion of writing that is not readable or pleasing to the writer
In some cases, this can indicate forgery, but is very common in normal handwriting to retrace letters or words
--Format and case: Format is the habit in which a writer uses to depict simple things like dates, numbers abbreviations, etc
Very important when people write checks
Case is a characteristic of a writer who might use upper case letters where lower case should be present.

23. Fingerprint vs. Handwriting
How many comparisons are required to identify handwriting as belonging to someone?
No set number, also up to the qualified expert examiner
How many comparisons are required to identify a fingerprint as belonging to someone?
No set number, it is up to the qualified expert examiner
--No single handwriting characteristic can in itself be taken as the basis for a positive comparison
The final conclusion must be based on a sufficient number of common characteristics between the known and questioned writing samples
There are no hard and fast rules for a sufficient number of personal characteristics
It is a judgment call made by the expert examiner in the context of each case
Another comparison between fingerprints and handwriting!!

24. Collecting Samples or Exemplars
Exemplar – Handwriting used as a standard for comparison with the document in question.
2 types of exemplars:
Dictated or requested
Undictated or collected
--the original is always preferred, but copies will work for analysis
--the evidence should be marked by the QDE with initials and date and if it can’t be marked on it should be placed in an envelope and sealed with initials and date
--rule of thumb: if you’re not sure if it should be initialed and dated, just do it, its worse to not do it when its needed
--always maintain a proper chain of custody and document everything you do so if someone questions you, you know exactly what you did and when and usually why
--when collecting, there should be enough exemplars to show natural variation of handwriting and some combinations of the letters and words on the questioned document
Collecting Samples or Exemplars
When collecting questioned documents, the original document is preferred
Would rather not have a copy, but can still use a copy for analysis
All evidence Should be marked by the document examiner
Usually initial and date
If the document cannot be marked it should be placed in an envelope and sealed with initial and date
Maintain chain of custody
Document everything you do
Colleting exemplars
The collection of an adequate number of known writings (exemplars) is most critical for determining the outcome of a handwriting comparison.
Known writing should contain some of the words and combination of letters present in the questioned document and be adequate in number to show the range of natural variations in a suspect’s writing.
The writing implement and paper should also be alike.
The writing of dictation and several pages may serve to minimize attempts at deception.

25. Activity 3: Unknown Handwriting
Match the question with the correct exemplar
Document your process of what and how you did everything
Get sources tonight

26. Questioned Documents Analysis

27. Ink Analysis Chemical composition of ink
Visible-light microspectrophotometer
Different wavelengths of light
Detect different inks, changes
Thin layer chromatography
--not only is handwriting examined, but the physical and chemical properties of the document as well
--Chem. Comp of ink can be used to verify if the same pen was used on the questioned documents and knowns
--U.S. Secret Service has an ink analysis program and maintains a library of over 6000 inks!!
--handwritten and printed notes can be analyzed
--in forensic science, nondestructive techniques should always be used first
visible light micro..is one of those
--different wavelengths of light can be used (IR and UV)
--the ink may glow, become transparent, or nothing happens
--In Thin layer chromatography (TLC)
Take a sample of ink out of a document, and place that “punch” in solvent
Dissolves ink out
Drop on paper or TLC plate (the stationary phase)
Put in liquid (the mobile phase)
Liquid travels up the paper and separates the components of the ink out.
In Thin layer chromatography (TLC)
Ink comparisons
Beyond handwriting, the questioned document examiner looks at the physical and chemical properties of the document
A study of the chemical composition of the ink used on documents may verify whether or not known and questioned documents were prepared by the same pen
The U.S. Secret Service has an ink analysis program and maintains a library of over 6000 inks
Handwritten notes as well as printed documents may be analyzed
Chemical tests of ink—ink solubility, paper chromatography, thin layer chromatography can be performed on printed or written material
Reveal a document was written with a specific writing instrument
Will reveal alterations: words added or removed from a document
A nondestructive approach to comparing ink lines is accomplished with a visible-light microsphetrophotometer
An ink will have specific chemical components
Same ink can be used in many pens (even different brands)
If look at writing under alternative light—UV, infrared, etc
Look for characteristics of ink—it may glow, may turn transparent, nothing may happen

28. Alterations Erasures Differing Ink Obliteration Disturbs paper fibers
--erasures aren’t always done with an erasure, it can be a sandpaper, razor blades or knives—anything that will remove what was originally there
--this is often obvious though because of the disturbance of fibers, but you have to use a microscope to visualize it
--different ink could react different than the original
--IR could make one ink luminesce and the other not do anything giving a clear indication that it was altered
--obliterations can also be detected by IR, the lower layer of writing might absorb at that wavelength which would make it luminesce while the top layer does not do anything
Alterations
Document examiners must deal with evidence that has been changed in several ways, such as through alterations, erasures, and obliterations.
Erasures
Erasures by rubber erasers, sandpaper, razor blades or knives attempt to removing writing
Action disturbs fibers of the paper which is readily apparent when examined with a microscope
If an alteration is made to a document with ink differing from the original, it can sometimes be detected due to difference in luminescence properties of the inks
Obliteration of writing by overwriting or crossing out to hide the original writing can be revealed by infrared radiation
May pass through the upper layer of writing while being absorbed by the underlying area

29. Types of Fraudulent Writing
Freehand simulations
Patching or retouching
Blunt starts and stops
Pen lifts
Tracing
Guidelines
Impressions
Poor line quality
Disguised writing
--Freehand simulations—an attempt to draw the signature or writing of another person
Very challenging
High chance that many individual characteristics will be incorrect
Possible to find evidence of patching or retouching of the written line to make it appear closer to the genuine signature
May also have blunt starts and stops, and pen lifts
--Tracing: is another common type
Involves using an original signature or writing as a guide to produce a fraudulent document
Indications of tracing may be guidelines around questioned signature
Graphite from a pencil
Remnants of carbon paper
Indented impressions suggest the original signature was traced over with a sharp object
Then pen used to go over impressions
Could also just put a paper over a signature and directly trace it
Will normally reveal poor line quality—line will be uneven and wavy, look like it’s been drawn slowly
Pin point tracing—poke holes in signature and make a connect the dots
All signatures will be exactly the same
--Disguised writing
Another form of fraudulent writing
Attempts to alter his or her writing to be able to deny authorship
Vary individual characteristics
Types of fraudulent writing
Alterations come in different known types
Freehand simulations—an attempt to draw the signature or writing of another person
Usually when working with a model signature
Requires that the individual maintain the same speed as the original writing and imitate the correct letter formations, height ratio, and pen pressure
Tracing: is another common type
See periodic dots in new signature
Disguised writing

30. Paper Analysis Class characteristics
--first, detect if additional pages added
--then look at class characteristics of the paper
different additives
size and thickness
color, brightness
watermarks
Next, analyze the paper itself
Detect if pages added to a document
Answer the question of where/when the document originated
Class characteristics
Location/number of staple holes
Different types of paper receive different additives during manufacturing
Paper size and thickness
Opacity, color, brightness
Water marks

31. Machine Analysis Typewriters, printers Class characteristics
Individual characteristics
--two most common requests:
whether the make and model of the typewriter and printing devices used to prepare the questioned document can be identified.
whether a particular suspect typewriter or printing device can be identified as having prepared the questioned document.
--this is done through a comparison of known equipment, these are the class characteristics
--but with use, damage is done causing slight variations from one machine to another, these are the individual characteristics
Machine Analysis
The two requests most often made of the examiner in connection with the examination of typewriters and printing devices are:
In order to do this, the individual type character’s style, shape, and size are compared to a complete reference collection of past and present typefaces.
As is true for any mechanical device, use of a printing device will result in wear and damage to the machine’s moving parts.
These changes will occur in a fashion that is both random and irregular, thereby imparting individual characteristics to the printing device.
The document examiner has to deal with problems involving business and personal computers, which often produce typed copies that have only subtle defects.
Another area of investigation relates to the typewriter ribbon, which may contain type impressions.

32. Activity 4: Chromatography
Make a mark on each piece of paper with each pen
Apply one drop of finger nail polish to each mark
Hold the paper vertically
Observe!!

33. Activity 4: Chromatography
What happened on each sheet?
Are there differences?
Are there similarities?
Look at the colors and number of dyes in each.

34. Any Questions?