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Chapter 12. Solutions. Solution. Solutions, in chemistry, homogeneous mixtures of two or more substances. Solute. The substance that is present in smallest quantity is said to be dissolved and is called the solute. The solute can be either a gas, a liquid, or a solid. Solvent.
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Chapter 12 Solutions Dr. S. M. Condren
Solution Solutions, in chemistry, homogeneous mixtures of two or more substances. Dr. S. M. Condren
Solute The substance that is present in smallest quantity is said to be dissolved and is called the solute. The solute can be either a gas, a liquid, or a solid. Dr. S. M. Condren
Solvent The substance present in largest quantity usually is called the solvent. The solvent can be either a liquid or a solid. Dr. S. M. Condren
Types of Solutions • Gaseous solutions - air • Liquid solutions - drinks • Solid solutions - steel Dr. S. M. Condren
Coke lists as its ingredients as: “carbonated water, high fructose corn syrup and/or sucrose, caramel color, phosphoric acid, natural flavors, caffeine”. What is the solvent? What are the solutes? Dr. S. M. Condren
Miscible and Immiscible Liquids Dr. S. M. Condren
Solution Terminology saturated • solution containing undissolved solute in equilibrium with the solution unsaturated • solution containing less than the maximum amount of solute supersaturated • solution containing more solute than is normally allowed Dr. S. M. Condren
Saturated Solution Dr. S. M. Condren
Ion-Dipole Attraction Dr. S. M. Condren
Dissolving of Ionic Solid in Water Dr. S. M. Condren
Temperature Changes with Solution Process Dr. S. M. Condren
Pressure Changes with Solution Process Dr. S. M. Condren
Molarity The number of moles of solute per liter of solution. molarity => M moles of solute M = -------------------- liter of solution units => molar = moles/liter = M Dr. S. M. Condren
Parts per Million #g of solute #mg of solute ppm = --------------------- * 106 = ----------------------- #g of solution #kg of solution #micro-L solute ppm = ----------------------- #Lof solution Dr. S. M. Condren
Molality • number of moles of solute particles (ions or molecules) per kilogram of solvent Dr. S. M. Condren
Boiling Point Elevation DT = Tfinal - Tinitial (DTb = bpsolution - bppure solvent) DTb = kb x m where kb => boiling point elevation constant m => molality of all solutes in solution Dr. S. M. Condren
Freezing Point Depression DT = Tfinal - Tinitial (DTf = fppure solvent - fpsolution) DTf = kf x m where kf => freezing point depression constant m => molality of all solutes in solution Dr. S. M. Condren
The freezing point of water is lowered proportional to the number of solute species present. In identical experimental circumstances, if NaCl is replaced with CaCl2 as a solute in water, how will the freezing point compare? higher temperature with CaCl2 lower temperature with CaCl2, no difference Dr. S. M. Condren
Why is it better to leave the “anti-freeze” in your cooling system during the summer? it might get very cold it keeps the engine from over heating saves time and money Dr. S. M. Condren