Foundations of Physical Science Workshop: Periodic Table Tiles

Chemical Equations and Recipies CPO Science

Key Questions How can we model the rearrangement of atoms that happens during a chemical reaction? How can we predict chemical formulas?

Chemical reactions and the environment What are the features of a chemical reaction? What general things happen on the atomic level? How can we model a chemical reaction on paper?

Obeying the law of conservation of mass For a completely correct model, we must be sure that there are equal numbers of each type of atom on left and right side.

Using the periodic table tiles to model chemical reactions Inventory and organize tiles in bag labeled Modeling equations Model the reactants only, using correct chemical formulas USING ONLY THE REACTANT TILES, try to form the products. What happened? Fill in the chart

What if products cannot be formed by using only reactant tiles? Something must be done so the law of conservation of mass is obeyed in our model Model the entire equation as is, and then fill in the chart.

Observe a chemical reaction Make sure the bag is sealed tightly Unscrew the vial top without opening the bag Mix the contents and note all observations

What evidence is there that a chemical reaction has occurred?

What are the reactants?

Calcium chloride: ice melt or driveway heat CaCl 2 Sodium bicarbonate: baking soda NaHCO 3

What about the red liquid? Phenol Red acts as an indicator The water component of the Phenol Red solution acts as a solvent for solid reactants

CaCl 2 + NaHCO 3 ?

What are the products? Sodium chloride: table salt NaCl Calcium carbonate: chalk CaCO 3 Carbonic acid: found in cola H 2 CO 3

CaCl 2 + NaHCO 3 NaCl + CaCO 3 + H 2 CO 3 H 2 CO 3 H 2 O + CO 2 heat

CaCl 2 + NaHCO 3 NaCl + CaCO 3 + H 2 CO 3

Molecular Crossword Game Similar to Scrabble Each player maintains 10 tiles Use periodic table with oxidation numbers to form compounds and molecules Add up atomic numbers to determine score

Playing Molecular Crossword Either side of tile can be used; + and arrow tiles are wild tiles Atoms may be arranged in any order, horizontal or vertical Oxidation numbers must add up to zero Score = sum of atomic numbers Correct challenge: challenger scores 25, player loses turn Incorrect challenge: challenger loses 25, play continues