BIOL 1F90 Lecture Notes - Lecture 6: Ethylene Glycol, Solution, Cryoprotectant
Document Summary
The amount of dissolved solutes affects the physical properties of a solution. Solute concentration = amount of a solute dissolved in a unit volume of solution: e. g. 1 g of nacl dissolved in 1 liter of water = 1 g/l. Does not directly indicate how many molecules of each substance are present: e. g. 1o g of glucose contains fewer molecules than 10 g of nacl. Number of moles dissolved per volume of solution is more informative. Properties of water that depend on the amounts of dissolved substances: do not depend on the specific type of particle, only its concentration, e. g. temperature at which a solution freezes or vaporizes. Addition of solutes as ethylene glycol to water: lowers its freezing point below 0 c, raises its boiling point above 100 c. Pure water has the ability to ionize to: hydrogen ions (h+, hydroxide ions (oh-) In pure water: [h+][oh-] = [10-7 m][10-7 m] = 10-14 m.