Chapter 6 - Solubility Solution – mixture of 2 or more substances Solvent – what you have the most of Solute – what there is the least of Example: 20% alcohol 80% H 2 O 60% alcohol 40% H 2 O Solute Solvent Solvent Solute Solute Solvent Solvent Solute

Solubility – the amount of solute that will dissolve in water (the solvent). Alcohol has infinite solubility in water The amount of salt that dissolves in water is dependent of temperature The higher the temperature, the more salt will dissolve The solubility of gases is also dependent on temperature the lower the temperature, the more gas will dissolve

Saturated – solution contains as much solute as it can hold at its current temp. (represented by the line on the graph) Unsaturated – The solution contains less solute than it can hold at its current temp. (represented by the area below the line) Supersaturated – The solution contains more solute than it can hold at its current temperature. (represented by the area above the line on the graph)

Colloid, Suspension and Solutions Colloid – when small suspended particles do not settle out of a mixture Will be cloudy, will scatter light Fog, milk Suspension – when particles in a mixture will settle out Will be cloudy, will scatter light Particles are usually larger than particles in a colloid Muddy water, dust in air

Solution – mixture is clear, particles are molecules or ions, will not scatter light Ocean water. Clean air

Acids Acid – anything that results in an H + ion when placed in water Examples:HCl, HNO 3, H 2 SO 4 Properties:tastes sour, reacts with metals, dissolves limestone Uses: digestion, in some foods, clean bricks and stone, used in manufacturing

Bases Anything that results in an OH - ion when placed in water Examples:NaOH, KOH, CaO Properties:taste bitter, feel slippery (soap), turn red litmus paper blue Uses: cleaning (soap and drain cleaners), cooking (baking soda), some stomach medicines

Reactions of acids and bases Acids and bases neutralize each other (they are opposites) Acid + base → water and a salt NaOH + HCl → HOH + NaCl A neutralization reaction is a double replacement reaction

pH A pH below 7 is acidic A pH above 7 is basic A pH of 7 is neutral