Homogeneous mixtures Can be solid, liquid or gas Aqueous solution Water that contains dissolved substances
SOLVENTSOLUTE The dissolving medium Water Gasoline Non-polar molecules will dissolve in other non-polar molecules! Dissolved particles Salt, sugar Oil, grease Remember: only the surface area of a solute can be dissolved!
Water is in constant motion (kinetic energy) water molecules collide with solute molecules Water is polar It is slightly + & - Attracted to ions SOLVATION – water surrounds each charged ion
Stirring (agitation) ↑ time b/c fresh solvent is brought in contact with the solute Only affects rate, not amt of solute that will dissolve Temperature ↑ temp ↑ time b/c it increases the kinetic energy of the solvent, which causes more collisions with the solute. Surface Area ↑ surface area ↑ time b/c more solute is exposed to the solvent
The amt of solute that dissolves in a given amt of solvent at a specific temp & pressure to make a saturated solution (g solute/100g solvent) contains the max amt of solute! If more solute is added it will NOT dissolve Unsaturated – doesn’t have all the solute that it can dissolve
TEMPERATUREPRESSURE Affects solids, liquids & gas Usually solubility ↑ as the temp ↑ Affects gases the most! Solubility ↑ as pressure ↑ HENRY’S LAW Solubility (S) is directly proportional to the pressure (P) S 1 = P 1 S 2 P 2
Number of moles of a solute dissolved in 1 liter of solution Dilute – small amt of solute Concentrated – large amt of solute
IV saline solutions contain 0.90g NaCl in 100mL of solution. What is the molarity?
Reduces the number of moles of solute per unit volume The total # of moles doesn’t change! M 1 V 1 = M 2 V 2
How many milliliters of aqueous 2.0M MgSO 4 solution must be diluted with water to prepare 100mL of aqueous 0.40M MgSO 4 ?