06 Notes - Colloids

06 Notes - Colloids - a colloidal dispersion, the beam is...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Aim: What other types of homogeneous mixtures exist? QQ: Why does boiling point go up as a solute is added to a solvent? Do Now: What do mayonnaise, aerosol, marshmallow and cheese have in common? Other homogeneous mixtures can be classified by the size of the solute particles dissolved in them… Suspensions: large particles in solution that will eventually precipitate out Example: sand in water Colloidal Dispersions: formed when particles are larger than those in a solution, but smaller than a suspension Example: milk Examples of Colloidal Dispersions Aerosol – solid or liquid in gas Fog, smoke Foam – gas in liquid Whipped cream, marshmallow Emulsions – liquid in liquid Mayonnaise, hand cream Gels – liquid in solid Butter, Jell-O How can we differentiate between a colloidal dispersion and a solution? Tyndall Effect: when a beam of light is shown through a solution, the beam is not seen, when passed through
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: a colloidal dispersion, the beam is visible. Electrolytic Solutions: solutions of ionic salts in water – have the ability to conduct electricity Ionic salts break apart into mobile ions: NaCl (s) + H 2 O (l) Na + (aq) + Cl-(aq) Can an aqueous solution of sugar conduct electricity? No! Molecular solids do not produce ions when in solution. If there are no ions, the solution will not be conductive. Conclusions Other homogeneous mixtures exists: Suspensions – large particles that will settle out Colloidal Dispersions – particles larger than a solution, smaller than a suspension Use the Tyndall effect to differentiate between solutions and colloidal dispersions Electrolytic solutions: Are formed when an ionic salt dissolves in water Have the ability to conduct electricity...
View Full Document

This note was uploaded on 01/01/2012 for the course CHEM 101 taught by Professor Donahue during the Spring '11 term at Long Island U..

Ask a homework question - tutors are online