1. Warm-Up: Form a group of 5 & find a spot on the lab counter.
You will be making Gak

2. GAK Pour 1” (inch) of glue into your cup.
Measure 15 mL of warm water in a graduated cylinder. Pour water into cup with glue and stir.
Add 2 drops of food coloring and continue stirring until all color and glue are mixed.
Measure 10 mL of Borax Solution in a graduated cylinder. Pour into cup with glue.
Mix until your polymer is formed.

3. Clean-Up
Rinse your plastic cup and knife. Make sure no gak is left on either.
DO NOT DUMP GAK DOWN THE DRAIN. Dump it in the trash and then rinse your cup.
Wipe down any spills that occurred during the lab.

4. Gak Discussion What are the reactants in this reaction?
Glue + Water + Borax
What are the products?
Gak Polymer

5. Objective
Students will be able to recognize a polyatomic ion and describe catalysts and inhibitors.

6. Agenda
Polyatomic Ions
Catalysts & Inhibitors
Exams

7. Polyatomic Ions
Previously, we learned that elements form compounds with a neutral charge.
There are some exceptions to this.
These exceptions are polyatomic ions.
You don’t need to memorize them, but you will need to recognize that they exist.

8. Common Polyatomic Ions
Oxidation #
Name
Formula 1+
Ammonium
NH4+ 1-
Acetate
C2H3O2- 2-
Carbonate
CO3-2
Chromate
CrO4-2
Hydrogen Carbonate
HCO3-
Hydronium
H3O+
Hydroxide
OH-
Nitrate
NO3-
Peroxide
O2-2 3-
Phosphate
PO4-3
Sulfate
SO4-2
Sulfite
SO3-2

9. Catalyst vs Inhibitor
You will read about either catalysts or inhibitors.
After reading and taking notes about your section, you will meet in a group of 4 other students who also read the same information.
You will compare your notes with one another.
Then, you will partner with someone who read a different text.
You will take turns teaching your partner what you read.

10. Catalysts & Inhibitors
Speed up a reaction by lowering the energy required for that reaction to take place.
Slow down or prevent reactions from taking place.
Allows for better control over a reaction.

11. Exams
You will have until Tuesday, December 10th to correct your Exams.

12. Exam Corrections
For Multiple Choice: You will need to state why your new answer is the correct one.
Do no just rephrase the question with the answer.
You need to show me you understand the question and the answer.
Physical vs Chemical – you must state why it is a physical or chemical change.
Formula Mass & Balancing Equations – You MUST show work for your new answer.
Short Answer – You MUST write a complete sentence.

13. Homework
Correct Exams