Journal Entry:

Consider this reaction:

Na₂CO₃(aq) + CaCl₂(aq) --> 2NaCl(aq) + CaCO₃(s)

1. Describe what you will observe when sodium carbonate, Na₂CO₃(aq) and calcium chloride CaCl₂(aq) are mixed.

2. Will mass increase, decrease or stay the same after mixing? Explain.

Learning Intentions

• We will  learn the law of conservation of mass and be able to explain how chemical reactions demonstrate this law.

Closing Task:

 You can describe what will happen in a chemical reaction and determine the conservation of mass for the reaction.

Content Standards being covered:

Student understands what the letters and numbers stand for in a compound formula, can use those letter and numbers to determine how many of each type of element there are in a formula.

Student can create mathematical representations of chemical reactions and use them to make calculations about products and reactants.

Students can use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction. (HS-PS1-7 and CCC Energy and Matter)