11WaterAdhesion – water molecules attracted to other slightly charged moleculesCapillarity – combination of the other two forces which causes the movement of water upward through tube cells (xylem)Transpiration pull
16Amount of heat needed to raise 1 gram of ‘stuff’ 1 degree Celsius. Specific HeatAmount of heat needed to raise 1 gram of ‘stuff’ 1 degree Celsius.Or…How well ‘stuff’ resists changing temperatures. (Water is stubborn)
19Most substances are most dense in their solid (frozen) state than in their liquid state. Water is different because of hydrogen bonding. Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% more space than water, so a liter of ice weighs less than a liter water. LIFE?????
21A solution is a substance that is uniformly spread throughout; (Homogeneous) Solvent – substance that does the dissolvingSolute – what is to be dissolvedExamples:Sugar and waterTea, coffee (Life?????????)
24Example of Importance to Life Properties of WaterPropertyExample of Importance to LifeCohesionWater flows, forming habitats and a matrix for biological moleculesHigh (specific) heat capacity (1g, 1OC)Water regulates constant internal body temperatureHigh heat of vaporization (1g to gas)Evaporation (evaporative cooling – sweating)AdhesionWater acts as a solventSolid less dense than liquidKeeps ponds and lakes liquid
25The more H+ present, the lower the pH # The more OH- present the higher the pH #
28WaterAcids – Compounds that release H+ ions (much like how NaCl dissociates in water but H+ are one of the most reactive ions on the planet)Bases – Compounds that release OH- (is the opposite of an acid; the OH- are as reactive as H+)Combining an acid and a base produces water and a salt
29Dissociation of WaterWater can dissociate into the hydrogen and hydroxide ionsH2O H+ + OH- (LIFE???????)