Name(s):__________________________________________ Class:______________ Date:____________
Law of Conservation of Matter Lab
Purpose: In completing this lab, you will demonstrate your understanding of the law of conservation of matter.
Remember matter can not be ________________ nor _________________!
Part One: Lego Reactions
Use the directions below to create your lego reactions. You must weigh the lego reactants and the lego products,
and fill in your data table. Use the key below to color-code your legos.
Element
Color of Lego
Hydrogen
Light blue
Sodium
Yellow
Chlorine
Dark Green
Oxygen
Orange
Mercury
Purple
Magnesium
Light Green
Iron
Dark Blue
Reaction #1: Sodium + Chlorine yields Sodium Chloride (Table Salt) Na + Cl
Mass of Na block:______g
NaCl
Mass of Cl block:_______g Predicted mass of NaCl:_______g
Actual mass of NaCl: ______________g
Reaction #2: 1 O2 + 2 H2
2 H 2O
Mass of 2 H blocks: _________g
Mass of 2 O block: __________g Predicted mass of 2 H 2O:__________g
Actual mass of 2 H2O:__________g
Reaction #3: Now it is time to see if you can balance the equations!
_____ H2 + ______Cl2
_____HCl
Mass of H2 block(s):_______g Mass of Cl2 block(s): _________g Predicted mass of HCl:_________
Actual mass of HCl:____________g
Reaction #4:
_____Mg + _______O2
_________
MgO
Mass of Mg block(s):_________g Mass of O2 block(s):_________g Predicted mass of MgO:________g
Actual mass of MgO:________________g
Reaction #5:
____Hg + ___O2
____HgO
Mass of Hg block(s):_________g Mass of O2 block(s):_________g Predicted mass of HgO:________g
Actual mass of HgO:________________g
Lab Part Two:
You will be testing the law of conservation of mass using Ziploc baggies, alka seltzer, and water.
Step 1: PUT ON YOUR GOGGLES. Measure out 40 mL of water and pour it into baggie #1. Place the piece of alkaseltzer in baggie #2. Place both baggies on the scale together and weigh them.
Starting mass: ___________g (should include two baggies, water, and alka seltzer.
NOW: cut the corner off of the baggie with the alka-seltzer in it. Place the piece of the corner in the baggie of
water. Now CAREFULLY place the alka-seltzer bag inside of the water bag. Do not let the alka-seltzer out of the
hole in the bag yet.
Zip the whole thing shut. Make sure you have pressed all of the air out. Now slide the alka-seltzer through the
hole into the water. After the reaction finishes DO NOT OPEN THE BAGGIE. Take the mass of the entire system.
Final Mass: ___________ g (whole system in Ziploc baggie)
Now, get the starting mass and final mass from two other groups, and fill it in below:
My Group:
Starting:
Ending:
Group 1:
Starting:
Ending:
Group 2:
Starting:
Ending:
Use the data you have gathered to answer the questions below:
Why is it important to keep the cut corner from the small bag inside the large bag in Step #5?
What does the Law of Conservation of Mass (Matter) state?
How does this lab support the Law of Conservation of Mass (Matter)?