PS-4.10  Recognize simple chemical equations (including single replacement and double replacement) as being balanced or not balanced.
It is essential for students to
·        Understand that a balanced equation represents a chemical reaction that rearranges atoms but does not create or destroy them. The same number of every atom on the reactant side must also be on the product side.
·        Understand the meaning of the coefficients and subscripts with respect to how many atoms are represented.