Students will see that it is not enough to do a simple set of observations to make a complete inference. By mixing the powders with different liquids, students will be able to determine the identity of each powder by matching their observations with facts about the mixtures.
Provide each group with three wax paper squares of each of the four powders (12 total). Again, it is important that powders are labeled and consistent with Part 1.
Each group should also get a small amount of each of the liquids, which can be provided in cups at each table. The liquids must be labeled.
Students should follow the procedures from their lab worksheet. They carefully record their observations in the chart. Tell them to be very specific and as accurate as possible with their descriptions. Most of their observations will be qualitative; however you can encourage quantitative observations such as the amount of time it takes for a reaction to occur.