Which solids will dissolve? Solvent & Solute Video Clip

Homogeneous vs. heterogeneous mixtures A mixture is a combination of two or more substances that are not chemically combined and that can be separated. Could you give me an example? Homogeneous vs. heterogeneous mixtures Homogeneous mixtures are of uniform appearance Heterogeneous mixtures consists of visibly different substances

Solutions Solution Chocolate milk Carbonated water Alloys A solution is a group of molecules that are mixed up in a completely even distribution. Chocolate milk Carbonated water Alloys

Solute and Solvent Solute Solvent A solute is the substance to be dissolved. Solvent A solvent is the substance doing the dissolving.

Solubility Solubility Factors that affect solubility Ability of the solvent to dissolve the solute. Factors that affect solubility Structure of the substance Temperature Pressure

Classification of solutions Saturated solutions have the maximum amount of solute dissolved in them. No more solute can be made to dissolve. Unsaturated solutions have less than the maximum amount of solute dissolved in them. This means that more solute could be added to the solution and the additional solute would still dissolve. Supersaturated solutions have more than the maximum amount of solute dissolved in them. Not all substances will form supersaturated solutions. http://genchem.chem.wisc.edu/demonstrations/gen_chem_pages/11solutionspage/crystallization_from_super.htm

Saturated Unsaturated Supersaturated

Suspensions The particles in suspensions are larger than those found in solutions. Components of a suspension can be evenly distributed by mechanical means, like by shaking the contents, but the components will settle out. Chalk in water Dust in air

Which solids will dissolve?

Properties of Water surface tension = water is pulled together creating the smallest surface area possible. Water has a high heat capacity. In order to raise the temperature of water, the average molecular speed has to increase. It takes much more energy to raise the temperature of water compared to other solvents because hydrogen bonds hold the water molecules together! “The specific heat is the amount of heat per unit mass required to raise the temperature by one degree Celsius.” 3. Density: Water is less dense as a solid! This is because the hydrogen bonds are stable in ice – each molecule of water is bound to four of its neighbors.