Slide 1Slide 2Water is a polar moleculeSlide 4Hydrogen BondingSlide 6Slide 7Liquid Water CohesionSlide 9Moderate TemperatureSlide 11Ice is less dense waterSlide 13Slide 142.14 Water is a versatile solventSlide 16Slide 17SalinitySlide 19Slide 20Slide 21Slide 22DensitySlide 24Slide 25Slide 26Light in the OceanSlide 28Slide 29Slide 30Slide 31Pressure in the OceanHHOSlight negative charge at this endSlight positive charge at this endNo overall chargeWater•Atoms in a covalently bonded molecule may share electrons equally, creating a nonpolar molecule•If electrons are shared unequally, a polar molecule is createdWater is a polar molecule–This makes the oxygen end of the molecule slightly negatively charged–The hydrogen end of the molecule is slightly positively charged –Water is therefore a polar molecule •In a water molecule, oxygen exerts a stronger pull on the shared electrons than hydrogenFigure 2.9(–)O(–)(+)(+)H H•The charged regions on water molecules are attracted to the oppositely charged regions on nearby molecules–This attraction forms weak bonds called hydrogen bonds Hydrogen BondingFigure 2.10AHydrogen bond•Like no other common substance, water exists in nature in all three physical states:Figure 2.10B–as a solid–as a liquid–as a gas•Due to hydrogen bonding, water molecules can move from a plant’s roots to its leaves•Insects can walk on water due to surface tension created by cohesive water moleculesLiquid Water CohesionFigure 2.11cohesionevaporation•It takes a lot of energy to disrupt hydrogen bonds–Therefore water is able to absorb a great deal of heat energy without a large increase in temperature–As water cools, a slight drop in temperature releases a large amount of heatModerate Temperature•Molecules in ice are farther apart than those in liquid water Ice is less dense waterFigure 2.13Hydrogen bondICEHydrogen bonds are stableLIQUID WATERHydrogen bonds constantly break and re-formLiquid waterIce•Solutes whose charges or polarity allow them to stick to water molecules dissolve in water–They form aqueous solutions 2.14 Water is a versatile solventFigure 2.14Ions in solutionSalt crystalCl–Na+Cl––– –––Na+++++Na+Cl––––––––––––++++++++++++++++++Salinity•Salinity is a measure of the amount of salt dissolved in water–Grams of salt left behind when we evaporate 1000 g of seawater–Called parts per thousand or parts per milleDensity•Density is the mass divided by the volume, or how much stuff fits in a space–Density = Mass/Volume•In saltwater–Salinity ↑ Density ↑–Temperature ↑ Density ↓•Denser stuff sits on top of less dense stuffLight in the OceanTransparency is the ability for of light to pass through a substance.•Some wavelengths penetrate deeper •Red light does not penetrate very deep.•Blue light penetrates the deepest.The transparency of water is a function of the amount of stuff in the water. •The more stuff suspended in the water, the less transparent the water is.Pressure in the Ocean•Pressure is a measure of force over a given area. –The weight of water is a force.•Deeper = more water above you = more weight•Therefore pressure increases with depth.•Pressure increases at the rate of about 1 atmosphere per 10m (or 30