Essential Question

• Why is water called the universal solvent if it does not dissolve everything?

Water

The Universal Solvent

Demo

• Compare the dry ice and ice • Into a large flask add:• 750 ml of water• 10 drops universal indicator• 75 ml of .1M NaOH• observe• Add several pieces of dry ice• observe

In your composition book…

• On the next clean page, • Title: Water• Date: Oct 31, 2013• Explain what you just saw in the Demo.• Include vocabulary words: Solvent, solute,

aqueous, solution, sublimation, dissolved gas

Lesson Frame

I will discover the unique (unusual) properties of water.

by observing water’s interaction with itself and other objects

mastered when I can describe water’s behavior

in terms of adhesion, cohesion, capillary action, and surface tension.

Activity 1

• Materials : video clip• 1. Observe the video.• 2. Write 2 - 3 sentences talking about how

water is unique based on the video. http://www.flixxy.com/water-drop.htm

For all of the following activities…

• Make a prediction of what you think will happen before you start procedure and record in composition book

Activity 2

• Materials: pipette tip, colored water, small medicine cup

• fill cup a quarter full of colored water• place pipette tip perpendicular in the

water • make and record observations on what

you see

Activity 3

• Materials: small plastic cup, water and card• fill plastic cup half way with water• place playing card over cup• While holding the card on top of cup, turn cup

upside down• Carefully (don’t squeeze) hold just the cup

(the card is now under the cup)• make observations

Activity 4

• Materials: 2 microscope slides, water, dropper

• place a drop of water onto one microscope slide

• place second slide on top of the other slide• try to separate by pulling them apart

Activity 5

• Materials: pre-soaked cotton string, water, 2 beakers

• pull string out of water beaker• pull string taut (tight) from one beaker to empty

beaker• raise the water beaker slightly above empty beaker • try to pour the water along the string to collect in

opposite beaker• make observations

Activity 6

• Materials: 1 plastic cup, water, small cork • Fill plastic cup half way with water.• Place the cork in the water• Make observations• Pull the cork out• Completely fill cup with water until it overflows• Place cork on water dome• Make observations

Activity 7

• Materials: plastic cup, water, needle• Fill a cup (almost to top) with water• Carefully set the needle on the top

of the water. Will it float?

Exit ticket

• Use the words/phrases on each slide to form a definition for each of the properties of water.

• Along with your definition, list an activity where you observed this property.

Adhesion

allows water

molecules

to stick to or spread out on

other

surfaces

instead of sticking

together

in a ball

Cohesion

Intermolecular attraction

which holds molecules

in a drop

of water

together

Surface Tension

is a result of

water molecules

strong cohesion

to each other

Capillary Action

is a result ofwater

sticking to

the inside of

a tube