Name:__________________________________________________ Date:____________________ Period #:______
Chemistry in a Ziploc
Purpose: To observe a chemical reaction, record observations, and identify the reactants and products of
the reaction.
{Sodium Bicarbonate}
{Acetic Acid}
NaHCO3 + CH3COOH  __________ + __________ + __________ + __________
{-------------Reactants-------------}
{----------------------------------Products----------------------------------}
Materials:
o
o
o
Sodium Bicarbonate
Dilute Acetic Acid
Graduated Cylinder
o
o
o
100 mL Beaker
Ziploc Bag
Scupula
Procedures:
1. Read the Procedures, Observations questions, and Clean up Instructions before you begin the
investigation.
2. Put on your safety goggles.
3. Use the scupula to transfer one scoop of the Sodium Bicarbonate powder from the container into the
Ziploc bag. Place the Ziploc aside
4. Go to the supply table to get a beaker of Acetic Acid to take to your table.
5. Use the graduated cylinder to measure 25 mL of dilute Acetic Acid from the beaker of Acetic Acid
provided by your teacher. Carefully pour the 25 mL of Acetic Acid from the graduated cylinder into the
50 mL beaker.
6. Lay the Ziploc containing the Sodium Bicarbonate flat on the table. Carefully stand the 50 mL beaker of
Acetic Acid in the Ziploc bag with the Sodium Bicarbonate and zip it shut. Make sure to zip the bag so it
is completely sealed.
7. Slowly tip the beaker so that the Acetic Acid spills into the Sodium Bicarbonate.
8. Start the Observations section the moment the reaction begins.
9. Do not open the bag until you have finished your observations and are ready to clean up.
Observations:
1. Describe what you see occurring. _____________________________________________________
________________________________________________________________________________
2. Can you hear anything? _____________________________________________________________
3. What do you feel when you place the bag on the back of your hand? __________________________
_________________________________________________________________________________
CLEAN UP YOUR MATERIALS AND RETURN YOUR MATERIALS TO THE LAB TABLE
IN THE FRONT OF THE ROOM BEFORE STARTING YOUR ANALYSIS.
o Dump the contents of the baggie into the sink and rinse the baggie. Dry it out with a paper towel and
return it to the front lab table.
o Return the beaker with the remaining acetic acid to the front lab table.
o Rinse out 50mL beaker and graduated cylinder. Place the graduated cylinder and the 50mL beaker
back on the lab table.
Analysis:
1. Why do you think the bag puffed out? __________________________________________________
2. What happened to the temperature of the bag? ____________________________________________
3. Did the chemical reaction take in heat or give off heat? _____________________________________
4. Endothermic reactions take in heat. Can you think of a reaction that takes in heat? In other words, can
you think of an example of a time when chemicals are mixed and the container feels cold?
_________________________________________________________________________________
5. Exothermic reactions give off heat. Can you think of a reaction that gives off heat? In other words, can
you think of an example of a time when chemicals are mixed and the container feels hot?
_________________________________________________________________________________
6. Do you think the same chemicals are still in the bag? ______________Why or why not: ___________
___________________________________________________________________________________
___________________________________________________________________________________
7. What are some signs that might indicate a chemical change/reaction has occurred?
_____________________________________________________________________________________
_____________________________________________________________________________________
Complete the table below for more practice counting atoms in a molecule.
Name of the Chemical Compound
or Molecule
Example:
Water
1. carbon dioxide
2. ozone
Formula
Elements Present & The Number of Atoms of Each Element
H20
2 Hydrogen, 1 Oxygen
CO2
O3
3. methane
CH4
4. table salt
NaCl
5. quartz
SiO2
6. calcium carbonate
CaCO3