Mixtures and Solutions Solute and Solvent
Matter Homogeneous mixtures Pure substances Solution Heterogeneous materials - can see two parts Homogeneous materials can see only one thing - one set of properties Mechanical Mixture Homogeneous mixtures They’re mixed together so well you only see one thing – it looks pure but it isn’t Pure substances You can only see one thing because there is only one kind of particle in it. Solution
Review Solutions Are solutions homogeneous or heterogeneous? Are solutions mixtures or pure substances? Mixtures What kind of states can a solution be? Solid, liquid, or gas What are the two “s” words that every solution must have? A solute and a solvent
In a salt water solution… Is salt the solute or the solvent? Solute Is water the solute or the solvent? Solvent What does the solute do? Gets dissolved What does the solvent do? Does the dissolving
A Salt Water Solution Solute (salt) Solvent (water)
Factors Affecting How Fast a Solute Dissolves Temperature Stirring or Shaking Crushing (Surface Area) Pressure
1. Temperature If we heat particles they will move faster The solvent will carry the solute particles away faster
So… Hotter = Dissolve Faster
2. Stirring or Shaking Stirring or shaking a solution moves the solute particles around so that they are closer to water particles the water particles can then attract them easily and carry them away!
So… Stir or Shake = Dissolve Faster
3. Crushing (Surface Area) When a sugar cube is broken into small pieces, the individual sugar particles can get closer to water particles the water particles can then attract them easily and carry them away!
Dissolving happens on the surface of particles When solute is broken up, there is more surface area where dissolving can occur broken up
4. Pressure Pressure is used to dissolve carbon dioxide gas in liquid pop Pressure forces gas particles into the spaces between the liquid particles gas
So… More pressure = Dissolve Faster
Exteme Example of Pressure Altitude Sickness and Nitrogen Narcosis (“The Bends”)