Properties of water Solid phase ______ dense than liquid High __________ heat Heat retention High latent heat of _______________ Evaporative cooling Sweating “______________ solvent” Dissolves most molecules All result from water’s chemical structure less specific vaporization Universal

Structure of water molecules Bent ________ molecular shape Characterized by _____ covalent bonding Polar molecule: dipole – positive side and negative side Oxygen = ____________ side Hydrogen = ______________ side ____________ bonding between molecules Accounts for many __________ properties Ice floats due to the difference in ________ polar negative positive Hydrogen physical density

The dissolving process Solution - _______________ mixture of ions/molecules from two or more substances Dissolving - the process of making a _____________ Components of a solution Solvent - present in __________ amount Solute - component ___________ in solvent Aqueous solution - solid, liquid or gas dissolved in _______ homogeneous solution largest dissolved water

Solutions - further details… Limits of solubility ____________ solutions – no more solute can be dissolved Insoluble substances, no noticeable dissolving Simple rule: “Like dissolves _______” _______ substances dissolve each other Polar substances can be dissolved by polar solvents Nonpolar substances are dissolved by __________ solvents. Fluids: gases and liquids ____________ fluids Can mix in any proportions w/o separating Immiscible fluids do not _______ Saturated like Similar nonpolar Miscible mix

Liquid solvents and solids “Like dissolves like” Oil and grease are not __________ in water; but the salt is. Why? Attraction between the ions of the salt crystal and the polar ends of the water molecules. soluble

Concentration of solutions Concentration - relative amounts of _________ and ___________ Relative terminology “_____________” - large amount of solute “_________” - small amount of solute More precise to take measurements of concentration Solute Solvent Concentrated Dilute

Concentration Measurements Concentration ratios Parts per million (ppm); parts per billion (ppb) By volume or weight Percent by volume Percent by weight Salinity Mass of salts dissolved in 1000 g of solution Molarity (M) Moles of solute in 1 liter of solution

Solubility Saturation Solute dissolving _______ limit ______________ between going in and out of solution Solubility ____________________ of saturated solution Depends on __________________ Gases: ____________ with temperature; ___________with pressure limit Equilibrium Concentration temperature decreases increases

Solubility Curve Which salt shows the greatest increase in solubility from 0-60oC? _______ At 50oC, 70 g of KNO3 is dissolved in 100 g of water. Is the solution saturated, unsaturated or supersaturated? ___________________ Which salt is least soluble in water at 60oC? ___________________ Which is the most soluble salt at 20oC? ___________________ What is the solubility of KCl at 80oC? ___________________ What it the temperature at which KNO3 has a solubility of 90g/100g of water? ________________

Solubility Curve Which salt is most soluble in water at 60oC? ___________________ Which salt shows the least increase in solubility from 0-60oC? _______ At 50oC, 40 g of KCl is dissolved in 100 g of water. Is the solution saturated, unsaturated or supersaturated? ___________________ Which is the least soluble salt at 20oC? ___________________ What is the solubility of KCl at 20oC? ___________________ What it the temperature at which KNO3 has a solubility of 20g/100g of water? ________________