General Chemistry Ch 9. Solutions Flashcards
Solutions
Homogenous mixtures composed of two or more substances, combine to form a single phase, generally the liquid phase
Solvent
Particles that surround solute particles via electrostatic interactions in a process called salvation or dissolution
Solute
Particles surrounded by solvent particles via electrostatic interactions in a process called solvation or dissolution
Solvation
aka dissolution, process where solvent particles surround solute particles via electrostatic interaction, most endothermic although dissolution of gas into liquid is exothermic
Dissolution
aka solvation, process where solvent particles surround solute particles via electrostatic interaction, most endothermic although dissolution of gas into liquid is exothermic
Aqueous solutions
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Hydration
Solvation in water
Solubility
The maximum amount of solute that can be dissolved in a given solvent and a given temperature, it is often expressed as molar solubility
Molar solubility
The molarity of the solute at saturation
Complex ions
aka coordination compounds, composed of metallic ions bonded to various neural compounds and anions, referred to as ligands, formation of them increases the solubility of otherwise insoluble ions (opposite of common ion effect), formation of the involves electron pair donors and electron pair acceptors similarly to coordinate covalent bonding
Coordination compounds
aka complex ions, composed of metallic ions bonded to various neural compounds and anions, referred to as ligands, formation of them increases the solubility of otherwise insoluble ions (opposite of common ion effect), formation of the involves electron pair donors and electron pair acceptors similarly to coordinate covalent bonding
Coordinate covalent bonding
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Percent composition by mass
Mass of solute per mass of solution times 100, used for aqueous solutions and solid in solid solutions
Mole fraction
Moles of solute per total moles, used for calculating vapor pressure depression and partial pressures of gases in a system
Molarity
Moles of solute per liters of solution, most common unit for concentration and is used for rate laws, the law of mass action, osmotic pressure, pH and pOH, and the Nernst equation
Molality
Moles of solute per kilograms of solvent, used for boiling point elevation and freezing point depression
Normality
Number of equivalents per liters of solution, the molarity of the species of interest and is used for acid-base and oxidation-reduction reactions
Saturated solutions
Are in equilibrium at that particular temperature
Solubility product constant (Ksp)
Simple the equilibrium constant for a dissociation reaction
Ion product (IP)
Can compare to Ksp to determine the level of saturation and behavior of the solution
IP
The solution is unsaturated, and if more solute is added, it will dissolve
IP=Ksp
The solution is saturated (at equilibrium) and there will be no change in concentrations
IP>Ksp
The solution is supersaturated and a precipitate will form
Formation or stability constant (Kf)
The equilibrium constant for complex formation, usually much greater than Ksp, increases the solubility of other salts containing the same ions because it uses up the products of those dissolution reactions, shifting the equilibrium to the right (opposite of common ion)
Common ion effect
Decreases the solubility of a compound in a solution that already contains one of the ions in the compound, the presence of that ion in solution shifts the dissolution to the left, decreasing its dissociation
Colligative properties
Physical properties of solutions that depend on the concentration of dissolved particles but not on their chemical identity
Vapor pressure depression
Follows Raoult’s law, the presence of other solutes decreases the evaporation rate of a solvent without affecting its condensation rate, thus decreasing its vapor pressure, also explains boiling point elevation - as the vapor pressure decreases, the temperature (energy required to boil the liquid must be raised)
Freezing point depression
Shift in the phase equilibria dependent on the molality of the solution
Boiling point elevation
Shifts in the phase equilibria dependent on the molality of the solution
Osmotic pressure
Primarily dependent on the molarity of the solution
Van’t Hoff factor (i)
For solutions that dissociate, this can be used in freezing point depression, boiling point elevation, and osmotic pressure calculations
