Solutions

Solutions – homogenous mixture: one substance dissolved in another solute – the substance being dissolved (fewer particles) solvent – the substance in which the solute is being dissolved in (more particles) ex. sugar water: sugar = solute & water = solvent

Water A solution w/ water as the solvent is an aqueous solution Water: the universal solvent Water is not always the solvent, it can also be the solute if there are fewer water molecules

Dissolving – particles spread out evenly Likes dissolve likes polar dissolves polar (and ionic, charges) nonpolar dissolves nonpolar (no charges)  Gases are more soluble in cold solvents, under high pressure ex. soda bottles

Ionization & Dissociation Ionic cmpds dissolve in a solvent & form ions Ionic solutions conduct electricity

Solubility The amount of solute that can be dissolved in a specific amount of solvent The amount of solid dissolved in water is given in units of grams of solid per 100 grams of water.

The amount of solid which dissolves in water at a particular temperature is different for different substances. You can plot a graph of the maximum amount of dissolved solid against temperature. Called a solubility curve Potassium Nitrate Solubility in grams per 100 grams of water Sodium chloride Temperature in °C

Concentration The amount of solute per unit volume of solvent Concentration = mass of solute (g) volume of solution (L) 1mL of H2O has a mass of 1 gram

Types of Solutions Unsaturated – will dissolve more solute Saturated – won’t dissolve more solute Supersaturated – has more solute dissolved than solution can normally hold

Increase Rate of Dissolving Increase surface area of solute Heat solvent (if dissolving a solid, gases dissolve better at lower temperatures) Stir the solute as it dissolves in the solvent Increase pressure for dissolving gases