Write a testable question about the materials you see in front of you. Must wear uniforms/IDs! 9/27/16 EBHS Admit Slip Write a testable question about the materials you see in front of you. Date: 9/27/16 Topic: Soap & Water Lab Page # ___

Learned new vocab about water Previous Water Lab Learned new vocab about water

Water Vocab Review Polar Hydrogen Bonding Cohesion Adhesion Universal Solvent Specific Heat Molecule with uneven charges The bonds between two different water molecules When water sticks to itself (ex. pile on penny) When water sticks to something else (ex. rain on glass) Water can dissolve almost any substance The amount of energy it takes to raise 1 g water 1 degrees Celsius

Surface Tension Hydrogen bonds between water molecules keep them together, and allow objects to rest on top

Soap & Water What happened to the number of water droplets the penny could hold when it had soap on it? Why do you think that happens?? https://www.youtube.com/watch?v= I_ocVSX7ZCI

Today’s Question: How does the type of soap impact water’s surface tension? Design & carry out an experiment.

Experimental Design What are key components? -Testable Question (share!) -Identify Variables (share!) -Specific Procedure (smiley face!) -Analyze Data

Control Group* The setup in an experiment that does NOT receive the changed variable (With liquid experiments, the control is usually just water)

Water & Soap Lab Question: How does the type of soap affect the number of water droplets that can fit on a penny? Materials: Hypothesis: Procedure: BE CLEAR AND SPECIFIC!! Data: Make a table! (Do multiple trials)

How does soap impact the hydrogen bonding between water molecules? Debrief Which soap had the greatest impact on water surface tension? How do you know? How does soap impact the hydrogen bonding between water molecules?

Soap weakens hydrogen bonds Which soap weakened the hydrogen bonds the most? How do you know?

Homework Experimental Design MCAS questions Can begin early if time allows…