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Water Unit. Warm Up: Write 10 facts you already know about water. What is WATER?. Water is a molecule It is also a compound. Why? What makes is a compound?. What is WATER?. The word water usually refers to water in its liquid state. What is WATER?.
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Water Unit Warm Up: Write 10 facts you already know about water.
What is WATER? • Water is a moleculeIt is also a compound. Why? What makes is a compound?
What is WATER? • The word water usually refers to water in its liquid state.
What is WATER? • Pure water has NO smellor taste, and a pH of 7 so it is not acidic or basicThat makes it NEUTRAL
Structure of Water • One water molecule is:Two hydrogen atoms (H2) chemically bonded to one oxygen atom (O)
Structure of Water • Hydrogen ends are slightlymore positive. • Oxygen end is slightlymore negative. • This means that water is a polarmoleculeWHY?????
Properties of Water Water has four properties that make it unique. • Cohesion • Adhesion • Capillary Action • Universal Solvent
Cohesion is when water molecules stick to otherwatermolecules (attract each other like magnets) • Cohesion at the surface of water is called surface tension.
More SURFACE TENSION PICS Surface Tension – Cohesion at the surface creates a thin “skin” on the water.
Adhesion is when water molecules stick to othermaterials Dew –water drops on a spider’s web.
Capillary Action • When a liquid movesup very narrow tubes because of cohesionand adhesionagainst gravity. • Ex: plants bring water up through their roots to their stems and leaves
Capillary Action • A meniscus is when the liquid “climbs” the sides of a graduated cylinder. glass surface
Universal Solvent • Water’s polarity gives it the ability to dissolve many different substances. • Almost every substance can dissolve in water over time.
Universal Solvent Almost…
3 States • Water is the onlysubstanceon Earth that commonly exists in all 3 states. • Liquid – Water • Solid – Ice • Gas – Water Vapor
Changing States Water can easily move between its three different states through several natural processes
Websites from the Presentation http://www.brainpop.com/science/earthsystem/water/ http://ed.ted.com/lessons/how-polarity-makes-water-behave-strangely-christina-kleinberg http://www.youtube.com/watch?v=oAY3yISf-24Other cool water related videos http://www.surfline.com/video/premium-partner-video/rubber-souls-new-zealand_103895(Surfing) https://www.youtube.com/watch?v=BickMFHAZR0(Capillary action in trees) https://www.youtube.com/watch?v=ph8xusY3GTM(Super-cooled water) https://www.youtube.com/watch?v=D-wxnID2q4A(Walking on water – sort of!)