This activity is used as a reinforcement activity following my use of JCE Classroom Activity #113: An Interlocking Building Block Activity in Writing Formulas of Ionic Compounds. It could be used as a stand alone activity to support writing ionic formulas and names.
Writing formulas and names of ionic compounds. Combining ions to form a neutral formula unit. There must be a specific cation and a specific anion for each formula unit.
Blue building blocks to represent cations & Red building blocks to represent anions.
For one set each of A – D as described in the table below, you will need
- Blue: three 3 x 1, nine 2 x 1, nine 1 x 1
- Red: six 3 x 1, eight 2 x 1, nine 1 x 1
Work with a partner. Create a table like the one below. (A sample set of data has been provided.)
|Set||CATION||# of cation(s)||ANION||# of anion(s)||FORMULA||NAME|
There are several stations set up around the room. You will have two minutes per station to find ions that work together to make compounds.
Cations = Blue Anions = Red
- Select a cation and an anion from the ions provided.
- Write the symbol for the cation in the CATION column.
- Write the symbol for the anion in the ANION column. (Remember that ions have charges…so you should show them with their symbol.)
- Put your cations and anions together so that they make a neutral compound (their charges add up to zero). Every formula unit will have a red line of blocks and a blue line of blocks.
- Record the number of cation pieces and the number of anion pieces that were required to make the compound.
- Write the formula of the compound you put together in the FORMULA column.
- Disassemble the formula unit. You may use these ions in new combinations.
- When time is up, move to the next set of ions.
Make sure that both of your names are on the table you submit for a grade.
one hour to create the sets using building blocks, baggies and permanent marker.
Ruddick, Kristie R. and Parrill, Abby L. An Interlocking Building Block Activity in Writing Formulas of Ionic Compounds, Journal of Chemical Education 2012, 89 (11), pp 1436-1438.