This document provides instructions for a forensics lab experiment involving testing different powders. Students are asked to bring specific supplies and complete data tables recording their observations of 5 powders using senses, solubility, iodine, and vinegar tests. Precautions are outlined to avoid contamination and ensure clean-up. The multi-step procedures involve taking pinches of each powder and recording 2 observations for each test. Students are told to cut contaminated stir sticks and wash testing trays between uses.
1. You will Need:
1. Pencil, One Colored Pencil
2. Forensics Intro – Was due
yesterday – If you were absent
please write ABSENT at the top or
FIELD TRIP
3. CSI Lab – to be passed out
2. 1.Final Exam CHANGE – 1 day
only - FRIDAY – ½ page of
notes, front side only, done by
hand – Target Concepts on-line
(Fri- June 6th
only)
2.Binder Check #4 – Due
Friday June 6th
3. 1. Long Hair MUST be tied back
2. Loose sleeves, bracelets must
be pushed up or removed.
3. Appropriate Lab Behavior
4. Consequence = Book Work-
See Side Board
4. -10 points will be taken for unclean labs
1. Sinks clean
2. Counters & Table Tops Clean & Dry
3. DO NOT sweep powders onto floors
4. DRY the inside of the Supply Bag
(Testing Equipment)
5.Powder Bags stacked straight up
inside Large Zip Lock Bag
Let Me KnowLet Me Know if supplies need to beif supplies need to be
added/changedadded/changed
5. 1. You may choose your partner for this
lab – CHOOSE WISELY
2. Please move to sit NEXT TO your
partner – No more than 4 people to a
table
3.Decide who is Partner A and Partner B
4. Partner B – Pick up One Set of 2
sheets from front bookshelf
5. Put Both names on ALL papers
7. Characteristic Partner #1 Partner #2
1. Eye Color
2.
3.
4.
5.
TOM JERRY
Physical Characteristics/Attributes – NO OPINIONS!
8. Problem: Can we identify a mixture of 2
different powders based on their
Physical & Chemical properties?
Hypothesis: IF we test five different
powders using our senses, solubility,
iodine, vinegar and heat test THEN we
should be able to identify a mixture of
any 2 powders.
10. Problem: Scientific Results must be
kept free of
contamination…..so…..
1. Do Not DOUBLE DIP!!!!!
2. Clean your hands each time you
use a new powder!!!!!
3. Stir sticks should be trimmed
when contaminated.
12. TESTS : Please complete each test on every powder before moving on to
the next test.
1.Senses:
A. Use your senses of sight, touch and smell. (mag. glass, wafting technique)
B. Record your observations into the chart.
Use a variety of adjectives to help establish the unique qualities of each
powder.
C. Three characteristics are required
2. Solubility:
A. Fill each of your vials with about 2.5 cm of water.
(from the sink….be careful with the pressure- TURN ON the SINK 1st)
B. Add in a “pinch” of powder.
C. Make one observation as the powder is “falling” into the vial. Record .
D. Stir in the powder with the stir stick.
E. Make a second observation once the powder has been stirred in.
Record.
*Since each tray has only 4 vials, you will need to clean the
tray out to test your fifth powder.
BRING DATA TABLE UP FOR TEACHER INITIALS.
14. 3. Iodine: Changes color in the presence of starch. (golden yellow-brown to black)
•Use the FLAT testing trays for this test.
•Measure a “pinch” of powder into each well.
•With the dropper, dispense three drops of iodine onto each powder.
•Make one observation as the iodine is placed onto the powder. Record.
•Stir in the iodine with the stir stick.
•Make a second observation once the iodine is stirred in. Record.
•Cut the tip of the contaminated stir stick off before using the stick again.
WASH, CLEAN and DRY TESTING TRAY
4. Vinegar: Chemical reaction between acids & bases results in bubbling and
exothermic reaction.
•Use the FLAT testing trays for this test.
•Measure a “pinch” of powder into each well.
•With the dropper, dispense three drops of vinegar onto each powder.
•Make one observation as the vinegar is placed onto the powder. Record.
•Stir in the vinegar with the stir stick. Cut the tip of the contaminated stir stick off
before using again.
•Make a second observation once the vinegar is stirred in. Record.
WASH, CLEAN and DRY TESTING TRAY
BRING DATA TABLE UP FOR TEACHER INITIALS.
16. -10 points will be taken for unclean labs
1. Sinks clean
2. Counters & Table Tops Clean & Dry
3. DO NOT sweep powders onto floors
4. DRY the inside of the Supply Bag
(Testing Equipment)
5.Powder Bags stacked straight up
inside Large Zip Lock Bag
Let Me KnowLet Me Know if supplies need to beif supplies need to be
added/changedadded/changed