Chapter 9 Flashcards
Solvation
Breaking of intermolecular forces between solute particles and between solvent particles with formation of intermolecular forces between.
Aqueous solution: water = solvent
Solubility
Amount of solute contained in solvent
Increase for solids: increase temperature
Increase for gases: decreasing temperature or increasing partial pressure of gas above solvent
Always soluble: Group I metals, ammonium, nitrate, acetate salts
Saturation
Maximum solubility of a compound at given temperature
* Can’t dissolve any more of solute just by adding more at current temperature
Molality
Mols solute/kg of solvent
Molarity
moles solute/L of solution
Normality
number of equivalents/L of solution
Dilution Formula
MiVi = MfVf
Mole Fraction
X = moles/total moles of all species
Percent Composition
mass of solute/mass of solution
Solubility Product Constant
Ion Product
Solution Behavior
Greater than solution Ksp -> precipitation
Less than solution Ksp -> dissolution
Colligative Properties
Properties that depend on the amount of solute present but not the identity of solute particles
Examples: vampor pressure depression, boiling point elevation, freezing point depression, osmotic pressure
Molarity (M) & Molality (m) in Water
- Nearly equal at room temperature
- Because 1 L solution = 1 kg solvent for dilute solutions
- In other solvents vary significantly because densities aren’t 1 g/mL like water
Raoult’s Law (Vapor Pressure Depression)
Ideal solution behaviour is observed when solute-solute, solvent-solvent, and solute-solvent interactions are all very similar