09/22/2013
Lab Date: 09/18/2013
Introduction/Background/Objective/Theory
Lab 3 consisted of Physical and Chemical Separations. The lab is based on the concept of Conservation of mass. This simply means mass cannot be created nor destroyed. This includes chemical and physical reactions as well. Also, Heterogeneous are chemicals that are not completely mixed, and homogeneous are chemicals that have been mixed together completely. Lab 3 will be an example that this law is true and can be used in finding the mass of an unknown compound given a total mass. Physical and chemical separations will happen to find the mass of three different compounds: Sand, NaCl, CaCO3.
Structures/Reaction/Mechanism
No Structural Compounds under investigation
Data
Substance
Addition of Water
Change
Addition of 6 M HCl
Change
NaCl
Sodium Chloride
NaCl+H2O
Physical Change
NaCl+6 M HCL
Physical Change
CaCO3
Calcium Carbonate
CaCO3 +H2O
No Change
CaCO3+6 M HCL
Chemical Change
Sand
Sand+ H2O
No change
CaCO3+6 M HCL
No Change
Sample Calculations
Analysis of Mixture
(grams)
Mass of sample Mixture
2.003
Mass of Empty Crucible for NaCl
42.313
Mass of Crucible and NaCl
43.231
Mass of NaCl
1.101
(Mass of Crucible and NaCl – Mass of empty =Mass of Nacl = Mass of NaCl )
Mass of empty crucible for Sand
40.555
Mass of Crucible and Sand
40.955
Mass of Sand
0.400
Mass of CaCO3
0.502
(Mass of Crucible + Sand - Mass of Crucible = Mass of Sand)
Mass of Sample Mixture – (Mass of Sand + Mass of NaCl) = Mass of CaCO3
Mass of Compound / Mass of Sample Mixture (g)
Percent Composition
0.1997
19.97 % Sand
0.5497
54.97 % NaCl
0.2506
25.06 % CaCO3
Results and Discussion
The data confirms the Law of Conservation of Mass. The table above shows which compounds react with others. This helps when figuring out what to do when separating a sample mixture. The lab shows that Calcium Carbonate does not react with water, but has a chemical reaction with Hydrochloric Acid. Sand has no reaction with either water or Hydrochloric Acid. NaCl has a physical change with water but does not change with Hydrochloric Acid. Using this information steps for separation can be