/26 Water’s Unique Properties Leave HW#12 out to be checked 1) Then, try to make your paper clip float! 2) Call Joe once your paper clip is floating. 3) Watch closely, record your observations. 4) Write a hypothesis for your observations.

FIND GOOD SURFACTANT MICELLE PICTURE MAYBE SCREEN SHOTS OF THE SOAP VID

Which of the following molecules has the dipoles drawn correctly? 21 Drawing Dipoles δ δ+δ+ A) B) C) D) δ δ+δ+ δ δ+δ+ δ δ+δ+

/26 Hydrogen Bonding Draw as many “hydrogen bonds” as you can between oppositely charge poles of neighboring molecules.

Water is ________________ and has an ___________________ oxygen atom which makes it very ______. The oxygen side of water has a partial ___________ charge and the hydrogen side of water has a partial __________ charge. This is called a ______. Water is attracted to other water molecules by _________ _____ where the negative _________ side of one water is attracted to the positive __________ side of another water molecule. Because water is very _______ and can hydrogen bond with itself it has several unique properties! unsymmetricalelectronegative polar negative positive dipole hydrogen bonds oxygen hydrogen Hydrogen Bonding polar

Water is ________________ and has an ___________________ oxygen atom which makes it very ______. The oxygen side of water has a partial ___________ charge and the hydrogen side of water has a partial __________ charge. This is called a ______. Water is attracted to other water molecules by _________ _____ where the negative _________ side of one water is attracted to the positive __________ side of another water molecule. Because water is very _______ and can hydrogen bond with itself it has several unique properties! unsymmetricalelectronegative polar negative positive dipole hydrogen bonds oxygen hydrogen Hydrogen Bonding polar

One of water’s unique properties is its high _________________. All liquids have surface tension that acts like a “_________” that is stretched tight across its surface. Water’s surface tension is especially high because water molecules are ______________ to each other by hydrogen bonding. When particles of the same substance are attracted to one another it is called ____________. surfacetension skin attracted cohesion Surface Tension

Water on a Penny cohesion Attraction between particles of the SAME substance co = together, with co-worker co-operate co-exist

A second unique property of water is how well it undergoes __________ ________. Water is so polar it can also be attracted to other polar ____________ while “sticking” to itself. This can be seen in the familiar ____________ shape formed inside small glass tubes. This attraction between water and other substances is called _______________and allows water to travel up materials against gravity. In trees for example, water is absorbed by the roots and travels up the xylem (veins of the tree). Water can “climb” up materials because as the water molecules are attracted up the walls of a surface (___________) they simultaneously drag other water molecules along (_______________). meniscus surfaces capillary action adhesion Capillary Action adhesion cohesion

adhesion Attraction between particles of the DIFFERENT substances (in this case the plant and water molecules) ad = to In this case “to” stick to something else Cohesion creates SURFACE TENSION Adhesion and cohesion working together create a meniscus and cause CAPILLARY ACTION Formation of a Meniscus

Examples of Capillary Action We have just learned that __________ creates ___________ ___________. Cohesion and ___________ together allows ____________ _______ to occur. cohesionsurface tension adhesion capillaryaction

Arrange 6 water molecules as shown This is the most common structure of ice! Imagine the crystal extending in all directions. 1. What shape does ice make? Notice the hole in the center. 2. Does the structure of ice take up more OR less space than the arrangement of molecules in a sample of liquid water? /28 Why Ice Floats Leave your Oil in Water CER’s out to be collected.

Hydrogen Bonding in Ice

As liquid water cools, the molecules slow down and hydrogen bonds arrange them into a hexagon shape Polarity of Water In liquid water, molecules are randomly and more densely arranged by changing hydrogen bonds

As liquid water cools, the molecules slow down and hydrogen bonds force a hexagon shape Hydrogen Bonding in Ice

Snowflakes are hexagons!

Lakes Freeze Top Down