Name:
Period:
Date:
Ziploc Bag Chemistry Mini-Lab
Question: How can you tell if it is a chemical or physical change?
Materials:
3 Ziploc bags, 3 paper cups, calcium chloride CaCl2 (flakes), sodium bicarbonate NaHCO3, water
Procedure:
Test #1 Calcium Chloride + Water
1. Find the mass of all the items going into the chemical reaction. (Reactants)
2. Weight of Dixie cup filled 1/3 of the way with water:
3. Weight of Ziploc bag + 1 scoop of calcium chloride:
4. Total Weight BEFORE the water and chemicals m
________ grams
________ grams
________ grams
5. Add the sample of calcium chloride to a Ziploc bag. Gently place a paper cup 1/3 full of water
inside the bag in an upright position. Squeeze the excess air out of the bag and seal the bag. Spill
the water out of the cup into the bag by shaking it. Look, listen, and feel. Record your
observations.
6. Record the mass of the sealed Ziploc bag after the reaction has occurred. ______grams.
7. Record your observations of the reaction in the data table below, and then record the mass of
materials before and after the reaction occurs in the table for #1.
8. Pour your liquid down the drain and put your materials in the trash.
Test #2 Sodium Bicarbonate + Water
9. Find the mass of all the items going into the chemical reaction. (Reactants)
10. Weight of Dixie cup filled 1/3 of the way with water:
11. Weight of Ziploc bag + 1 scoop of Sodium Bicarbonate
12. Total Weight BEFORE the water and chemicals m
_______ grams
_______ grams
________ grams
13. Add the sample of NaHCO3 to a Ziploc bag. Gently place a paper cup 1/3 full of water inside the
bag in an upright position. Squeeze the excess air out of the bag and seal the bag. Spill the water
out of the cup into the bag by shaking it. Look, listen, and feel. Record your observations.
14. Record the mass of the sealed Ziploc bag after the reaction has occurred. ______grams.
15. Record your observations of the reaction in the data table below, and then record the mass of
materials before and after the reaction occurs in the table for #2.
16. Pour your liquid down the drain and put your materials in the trash.
Test #3 Sodium Bicarbonate + Calcium Chloride + Water
17. Find the mass of all the items going into the chemical reaction. (Reactants)
18. Weight of Dixie cup filled 1/3 of the way with water:
_______ grams
19. Weight of Ziploc bag + 1 scoop of Sodium Bicarbonate and 1 scoop of Calcium
Chloride.
_______ grams
20. Total Weight BEFORE the water and chemicals m
________ grams
21. Add the samples of CaCl and NaHCO3 to a Ziploc bag. Gently place a paper cup 1/3 full of water
inside the bag in an upright position. Squeeze the excess air out of the bag and seal the bag. Spill
the water out of the cup into the bag by shaking it. Look, listen, and feel. Record your
observations.
22. Record the mass of the sealed Ziploc bag after the reaction has occurred. ______grams.
23. Record your observations of the reaction in the data table below, and then record the mass of
materials before and after the reaction occurs in the table for #3.
24. Pour your liquid down the drain and put your materials in the trash.
Data: Observation of mixing... What did you see happen, did you feel any change in temperature?
Record all your observations below!
#1 Calcium chloride and
water
#2 Sodium bicarbonate and
water
#3 Sodium bicarbonate and
calcium chloride
How does it change?
How does it change?
How does it change?
Mass of Reactants _____g
Mass of Reactants _____g
Mass of Reactants _____g
Mass of final product ____g
Mass of final product ____g
Mass of final product ____g
Change in mass _____g
Change in mass _____g
Change in mass _____g
1. SPECIFY which changes you observed were chemical and/or physical
JUSTIFY YOUR ANSWER WITH EVIDENCE FROM THE LAB!
Sodium bicarbonate and
Calcium chloride and water
Sodium bicarbonate and
water
calcium chloride
Chemical changes?
Chemical changes?
Chemical changes?
Physical changes?
Physical changes?
Physical changes?
2. What sort of things signified a chemical change versus a physical change? (For example... If it
_____________ it was definitely a chemical change.)
3. What are the possible gases that could be produced in this experiment? Look at the chemical
formula for the reactants (stuff you mixed).
4. Did the mass change in any of the reactions from the initial reactants (things you put in) to the
final product? (What you had after the reaction)
5. Go to http://www.learner.org/channel/courses/essential/physicalsci/session4/closer1.html or
(http://goo.gl/ktNsi2)
- What is the distinction between chemical and physical changes?
Physical change is when...
Chemical change is when...