Tuesday 9/27/10 DateAssignmentPage 9/27Mystery Mixture

Today’s Objectives 1.Learn about and practice safety measures and procedures in the lab. 2.Substances are a form of matter. Each substance has a unique composition and distinct properties.

Strategies for Meeting Objectives 1.Listening to and practicing safety measures and procedures in the lab. 2.Participate in an activity that involves 3 different substances.

Prep 1s Get tub, check all materials are there. 2s Get 1 cup of water—make sure you use your table’s sink–and paper towels. 3s Get safety glasses. 4s Take both beakers and put 1-5 ml scoop of Mystery Mixture in each beaker

Materials For Each Group mL beakers 2 pipettes 4 hand lenses 1 cup (for water—2s get) 2 wooden craft sticks Protective eyewear (3s get)

Part One 1.Write the heading: Part One. 2.Put on protective eyewear. 3.Put one 5-mL spoon of the mystery mixture into the beaker. 4.Observe the mixture. (Do not touch or taste the mixture.) 5.Record your observations (size, appearance, color, texture).

Part Two 1.Write the heading: Part One. 2.Add one drop of water to the mystery mixture in the cup. 3.Take turns adding additional drops of water to the cups. Observe the mixture. 4.Record your observations (number, size of bubbles, how long they last…).

Clean Up 1s make sure all materials are there, put tub back in correct spot 2s empty water, dries table 3s put safety glasses away 4s dry both beakers and cups 32 41

Questions 1.What happened when you added one drop of water to the mixture? 2.What happened when you added a second drop? 3.Did it fizz and bubble every time you added a new drop of water? 4.What causes the bubbling and fizzing? 5.Why does the mixture stop fizzing after five pipettes of water have been added?