Activities
Exploration with solids and liquids. First explore granular or powdered sugar, fine sand, and Kool-Aid. Look at them with hand lenses and draw pictures.
Put a small spoonful in a small container of water. Try to filter them through a coffee filter. Put a small puddle on a plate and let the water evaporate.
Take a quarter of a small spoonful of each of the powders and drop 5-10 drops of the liquids on each.
Powders: baking soda, baking powder, baby powder, and corn starch.
Liquids: water, vinegar, and iodine.
Test different liquids for pH. Liquids: vinegar, shampoo, liquid soap, hair conditioner, ammonia.
Try different tests to identify mystery substances.The above list of activities are often given as a learning sequence for students to construct concepts of physical and chemical change.
Without appropriate scaffolding for students to transform their observations into scientific conceptual understanding the following results are likely when students are asked to write about what they know or still want to know about chemicals.
I know some are different colors. Some chemicals fizz and dissolve so you can't see them and others are cloudy. Some look like glue. Some are good and some bad.
Why don’t it blow up?
I know chemicals can dissolve, turn colors and fizz or bubble. A lot of chemicals dissolve, I know chemicals can be acid, Base or Neutral. some can be a solution or suspension. They can be a crystal.
Chemical can be dangerous. You need to follow the safety rules: Do not taste, wear your goggles, and follow directions.
Robert Sweetland's Notes ©