Chemical Reactions and Equations
Purpose

The “Chemical Reactions and Equations” lab was to observe physical and chemical properties associated with chemical reactions, to make note of/document the evidence of the chemical reaction, to practice balancing equations, to predict the products that form from a reaction, and to have an understanding; did the elements bond, break apart, or did they switch partners in the reaction (determine what happened to the reactant/s as they formed new product/s).
The lab demonstrated the law of conservation of matter, in form and function; the form being the equation, and the function being the results of the individual experiments. According to the lab manual; “In a chemical change, a substance is changed to give a new substance with a different composition and different properties”. The lab manual continues to read “However, the total number of atoms of each element in the reactants is equal to the total number of atoms in the products”; yet again, demonstrating the law of conservation of matter.

Pre-Lab and Report Sheets attached.

Discussion

It is interesting to note in section C. (Metals and HCl) of this lab that hydrogen cations are released as part of a single replacement reaction. It follows the predictability that an acid is a substance that releases hydrogen cations in solution. Wanting to understand the way things work is a human condition, and in knowing how reactions of certain elements work is the key to manipulating them to our advantage. At the beginning of the semester I knew hardly anything about what seeing a chemical equation meant and what it “read” and now when I see {Cu+2HCl >>>CuCl2+H2} I know I’m seeing an acid because I know hydrogen cations are released in solution.
Our lab book does not cover the “activity series concept”, as our text book does. But, it is also interesting to note how the “activity series” is a tool which allows us to predict what elements are going to bond more readily to one another and which are not. “In an activity series (or electromotive series), a sequence of metals is arranged according to their ability to undergo reaction”. Our textbook continues to read, “The metal that displaces to the other metal does so because it has a greater tendency to undergo a reaction”. There are also “a few metals that are so reactive that they react directly with water at room temperature”’; they are deemed “active metals”.

Conclusion

Rules and laws have been established by our forefathers (and foremothers) about how the science of chemistry works,