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Science: Forensics Case 5 - The Ink Is Still Wet: Using colorimetry to identify an unknown ink

by Texas Instruments

Overview

In this activity, students identify the ink of a ransom note to match suspects. They identify an unknown ink by its light absorbance characteristics. The experiment set up used is to measure a solutions absorbance of different colors (wavelengths) of light.

Key Steps

Using the four settings on the colorimeter (Red, Green, Blue, Violet), solutions of different brands of ink pens are tested.
With the data compiled, each ink has a distinct profile making it possible to see if the ink sample from the suspect matches the specialized ink contained in the ransom note.

Related Activities

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Forensics Case 2 - Bouncing Back: Using ground-penetrating radar to locate buried objects
Forensics Case 3 - Name That Tune: Matching musical tones through waveform analysis
Forensics Case 4 - Flipping Coins: Density as a characteristic property
Forensics Case 6 - Measuring Momentum: Using distance moved after impact to estimate velocity
Forensics Case 7 - Drug Tests: Identifying an unknown chemical
Forensics Case 8 - No Dumping: Using soil characteristics to link suspects to a crime scene
Forensics Case 9 - Killer Cup of Coffee: Using colorimetry to determine concentration of a poison
Forensics Case 10 - Dropped at the Scene: Blood spatter analysis
Forensics Case 11 - Ashes to Ashes: Using evaporation rate to identify an unknown liquid
Forensics Case 12 - Hit and Run: Using information from an event data recorder to reconstruct an ac
Forensics Case 13 - Life in the Fast Lane: Using skid marks to determine vehicle speed
Forensics Case 14—Hot Air, Cold Body: Using Newton's Law of Cooling to Determine Time of Death

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Alignment

Device

Software

Applications

EasyData® for TI-83 Plus and TI-84 Plus

Vernier EasyData™ for TI-84 Plus CE

Science: Forensics Case 5 - The Ink Is Still Wet: Using colorimetry to identify an unknown ink

Overview

Key Steps

Related Activities

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